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# Measuring the rate of photosynthesis lab answers

measuring the rate of photosynthesis lab answers 4 00:01:30 13. Post-Lab Questions. In Experiment 1, we extracted pigments of spinach and smeared them onto filter paper, which was then placed in a graduated cylinder with 1 cm of solvent at the bottom. Part B: 1. Photosynthesis converts _____ energy into the _____ energy of sugars and other organic compounds. here consider the present state of this hypothesis by evaluating the modern pertinent The rate of leaf net photosynthesis, which may be measured in terms of ing (1966) obtained similar evidence in an experiment in which the leaf area. U can place a plant in a secure container and measure the drop in Co2 levels area with regular what are the answers for the photosynthesis lab in gizmos Launch Gizmo Study photosynthesis in a variety of conditions. Usually In this lab, students will be testing whether or not aquatic plants do photosynthesis in the dark or light, and also testing if they do cellular respiration during the dark or light. Light is absorbed by the chlorophyll inside the chloroplast. It is not quite so easy to demonstrate the other reactions in photosynthesis. (Emphasis is on illustrating inputs and outputs of matter and the transfer and transformation of energy in photosynthesis by plants and other photosynthesizing organism’s). What do you think the bubbles are? Oxygen 2. Photosynthesis Lab Gizmo : Lesson Info : To answer this problem, we would to look at the table of results. Some of the CO2 and/or O2 that we measured was most likely already. AP Biology Lab #4: Plant Pigments and Photosynthesis OVERVIEW: In this lab you will: 1) Separate plant pigments using chromatography. 045 ate 1. Calculate the change in volume for each measurement time. 1 Colour change and inferences that can made from the results: Tube 1 (leaf extract + DCPIP) colour changes until it is the same colour as tube 4 (leaf extract + distilled water). Many of us  18 May 2016 In this experiment we follow the photosynthesis rate in Elodea by measuring the rate of oxygen production. Biology-Lab-Four-Plant-Pigments-and-Photosynthesis - AP Lab Four Plant Pigments And Photosynthesis Answers LAB FOUR PLANT PIGMENTS AND PHOTOSYNTHESIS OVERVIEW In this lab you will: 1. From your graph, what is the effect of temp on the amt of oxygen that water at differnet temps can hold? Elodea Lab Answer Key. If the rate of photosynthesis increases, so does the amount of oxygen and Carbon Dioxide used. A hectare (e. (4) The graph shows blood pressure measurements for a person at rest. Once gas is evolved by photosynthesis, the leaf discs rise and fall. Using the button on top of the MultiSpeQ, open it, and clamp down on a leaf. Summarizing (2 pts) Briefly summarize the process of photosynthesis. Elodea is an aquatic plant that is easy to use for photosynthesis experiments. Make a chromatogram strip. This is converted, through photosynthesis, into Oxygen. effect of light intensity on the rate of photosynthesis? A. Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a by-product. By measuring the rate at which the bubbles are produced it is possible to tell how fast the plant is photosynthesizing. In this investigation, you will measure oxygen Photosynthesis Lab Gizmo : ExploreLearning. The method we use is actually a measurement of the carbon dioxide catch: We enclose a small part of the tree inside a chamber and follow the change of CO 2 concentration in the air of this chamber. Step 1 is Step 2 is to take note of the units of measurement. Measure out 10ml of boiled water and place it in test tube 2. Controlled Variables: CO 2 concentration of the environment. Photosynthesis is a food making process for algae and plants. I kept the light bulb at 5cm away from the test tube and placed a coloured filter in front of the light so that the colour of the filter shone on the plant. Gizmo, you can monitor the rate of photosynthesis by measuring oxygen production. Set the light intensity to 0 and count the number of bubbles produced over 30 seconds using the clock. Dec 02, 2014 · *The floating disk method indirectly measures photosynthesis by measuring oxygen formation, which is one product of photosynthesis. Is light important for photosynthesis? Photosynthesis is the process by which plants take carbon dioxide from the atmosphere, add water, and use the energy of sunlight to produce sugar. 7. temple. Photosynthesis is one of the most important anabolic chemical reactions that allows life to exist on Earth. On the graph, notice the Photosynthesis virtual lab answer key Check out this awesome Our Reports About Photosynthesis Lab Experiment for writing techniques and actionable ideas. 11. Both ATP and NADPH are necessary for carbon fixation. Measure and pour Answer the following questions using data from your lab AND internet research if needed. A by-product of photosynthesis is oxygen. The FLDA actually measures the rate of photosynthetic oxygen production minus the rate of respiratory oxygen use during the same period. Be sure to clearly indicate the x and y axes, the units used, and the graph title(s). 16 Apr 2020 Lesson Activity Answers to: How to Interpret Graphs. PLAY. Use your answers to other Experiment 1 questions above for the photosynthesis rate at a light intensity of 10. Adapted from: John S Olson, Dist. This system is also used to measure actual and saturated photosynthesis rates, transpiration rates, stomatal conductance and water use efficiencies. Honori Yamada Biology SL 2 Mar/12/11 The Effect of the Rate of Photosynthesis on Different LeavesIntroduction: Oppositely from cellular respiration, photosynthesis is a chemical reaction inwhich autotrophs or green plants produce their own food and as a byproduct, theysynthesize glucose and oxygen. 1-888-302-2840 1-888-422-8036 Lab Gizmo Answers Photosynthesis Lab Gizmo Answers The complex series of chemical reactions is summarized by the following formula: 6CO 2 + 6H 2 O + light energy → C 6 H 12 O 6 + 6O 2 In the Gizmo, what light intensity and CO 2 level do you think will maximize the rate of photosynthesis? Student Exploration: Photosynthesis Lab (answers) Start Photosynthesis Lab . and Chasson, R. This will be done by measuring the bubbles of oxygen and having a bulb for the light intensity variable. Which is the most suitable chamber for it? Since its 3 dimensional, how will the area of ear be taken care of One of the simplest measures of photosynthesis is just measuring how much your plants grow (i. C. Read the directions on the paper before starting. 24 Jan 2020 We reported a fast photosynthesis measurement (FPM) method for phenotyping photosynthesis of excised tillers in environment-controlled lab conditions. today: The products of photosynthesis — oxygen and carbohydrates — are the reactants for cellular respiration, and vice versa. 065, Q3= 0. Fill in the following answers as you watch. Write the chemical equation for photosynthesis. Write. 52 or higher. In an advanced or AP Biology course, class time is a precious commodity. cyanobacteria and algae) convert light energy from the sun into chemical energy. , e) analyze the effect of light on the rate of photosynthesis by: The materials required for this experiment for each group of the students are:. Title and number your data table. Jul 19, 2020 · To measure a plant’s growth rate, use a ruler or measuring tape to measure from the base of the plant to its highest point. There are 2 things we can quickly measure in this experiment (the dependent variables): amount of oxygen produced, or, amount of carbon dioxide used. The soap dilution we will be using is 5ml of soap for 250ml Factors affecting photosynthesis. All books are in clear copy here, and all files are secure so don't worry about it. Write a hypothesis for the relationship between light intensity and photosynthesis rate (as measured by ATP production in the light dependent reaction). • Explain the relationship of photosynthesis to the observations made during the experiment. Regardless of the topic, subject or complexity, we can help you write any paper! 3 Describe how you might extend this practical to investigate the effect of light intensity on the light-dependent reactions of photosynthesis. Photosynthesis occurs at a faster rate in a highly humid environment. Photosynthesis is the process of trapping light energy and converting it into forms of chemical energy that 4) NADPH is in short supply in the chloroplast - this is the rate-limiting link that keeps these Measure about 75ml of tap water into each of two 250 ml beakers. 3. Water and carbon enter the chloroplast…. In this lab, you will be experimenting with how different variables affect the rate of photosynthesis. Based on your data, draw a conclusion regarding how light intensity affects the rate of photosynthesis. The graph of photosynthetic rate versus temperature presents a curved appearance with the peak rate occurring close to room temperature. Question: "For the second year in a row measuring the rate of photosynthesis using spinach leaves, DPIP and a Spec 20 have failed to show any activity with spinach chloroplasts. ^The hypothesis was… _ a. Purpose: The purpose of this investigation is to measure the rate of photosynthesis in spinach leaves by measuring the length of time it takes for leaf discs to generate enough oxygen to float. The average amount of CO 2 absorbed from the air in one hour on a bright day by a given sample of leaves can be determined when equal volumes of air are simultaneously passed over the green leaves in a chamber exposed to light and then through a solution of baryta of Apr 11, 2009 · Favorite Answer Use the aquatic plant Elodea and place in beakers containing water of different temperature and collect the oxygen given off in graduated tubes placed over the plant. Where in the cells of the leaf do you find air spaces? In most of the photosynthetic experiments, the rate of photosynthesis is determined either by measuring the volume of OI 2 evolved per unit time or mg or ml of O 2 evolved as estimated by titration. List your materials for this lab. The process is summarized by the following reaction: 2 H 2 O + CO 2 + light → carbohydrate (CH 2 O) + O 2 + H 2 O To determine the net rate of photosynthesis, one could measure one of the following The purpose of this experiment was to determine the effect of sodium bicarbonate on the rate of photosynthesis of spinach leaf disks. PhotosynthesisL abSE_Key (1). Plants use some of the oxygen they produce, but most of it is released. Glucose molecules can later be bonded together using dehydration synthesis to form polysaccharides (complex carbohydrates) like starch or cellulose. Thanks for contributing an answer to Biology Stack Exchange! Please be sure to answer the question. The Photosynthesis Reaction. edwardsw. The time it takes for a certain number of leaves to float can be used to calculate the rate of photosynthesis. Oxygen dissolves into water when aquatic autotrophs release oxygen as a byproduct of photosynthesis. Yin et al. Experiment -Measurement of Photosynthesis There are various set-ups that can be used to measure the rate of photosynthesis, each relies on counting the oxygen produced during the reaction. The rate of photosynthesis is measured by one of the following methods: By measuring (I) the volume of CO, consumed (2) volume of oxygen liberated (3) amount of carbohydrate accumulated. Photosynthesis: Why Do Temperature and Light Intensity Affect the. None of this gas would be present in an atmosphere of pure oxygen. 5. Introduction . Be sure to identify the subunits that adhere to paper during chromatography. carbon dioxide is a reactant that is used up during photosynthesis. Design an experiment. Along the course of this lab, the processes of photosynthesis and respiration were studied at length. ------------------------------------- 00:00 Preparing the sample  What factors may affect rates of photosynthesis and cellular respiration? between stomata, and note if they are open or closed in their lab book or on their answer. The hypothesis relates to the unit because without CO2 the Calvin cycle wouldn't be able to take place, which means that the beaker without CO2 will not go through photosynthesis. In the process of photosynthesis, carbon dioxide (CO 2 ) and water (H 2 O) undergo a series of chemical reactions initiated by light energy to produce glucose (C 6 H 12 O 6 ) and oxygen gas (O 2 ). In the Photosynthesis Lab Gizmo, you can monitor the rate of photosynthesis by measuring oxygen production. 1. Since I followed the directions exactly for producing a chloroplast solution and knowing my Spec 20s work properly, I am left to wonder about DPIP. Thus, the use of this lesson plan allows you to integrate the teaching of a climate science topic with a core topic in the Biological Sciences. By creating algae beads (made of algae and sodium alginate solution), they indirectly observe the change in concentration of oxygen in beads that are exposed to different amounts of light. spinach, ivy, pokeweed), timer, light source (60 watt light bulb recommended), hand-held hole punch, and beakersStorage: Room Temperature If students are not readily responding with the correct answers, take a few minutes to spiral back and conduct a brief review of the photosynthesis reaction. CELL RESPIRATION PRELAB VOCABULARY: 1. Essay on The Rate Of Photosynthesis: Lab report 1) Construct a graph of your data 2) Using the graph, estimate the time at which 50 percent of the leaf disks were floating on the surface. Can you think of a way to how you might measure the gross rate of photosynthesis with this technique? Wrap-up. that you think may affect the rate of photosynthesis. Write a problem question to test effect of light intensity. measure the rate of photosynthesis in isolated chloroplasts using the dye DPIP. Hopefully, this procedure that is not a procedure is enough information to help you develop your own protocol to answer your own questions with Photosynthesis Lab Gizmo Answer Key Pdf - Answers Fanatic Associated to photosynthesis lab gizmo answer key pdf, Answering solutions are what company and others put to use prior to the cellphone organisations offered voice mail and in advance of there had been answering machines. If I wanted to mix 1000ml of . Spell. In other words, we are measuring the rate at which each treatment takes to complete photosynthesis. Based on how little or how well students responded to the initial question, decide if you will use the chemical equation or the photosynthesis diagram as the "anchor document" for the review. What gasses are being consumed and produced in photosynthesis? 3. In the following some of the commonly used methods of measuring photosynthesis are given: I. leaves was directly proportional to the rate of photosynthesis The measurements of rates of photosynthesis TO answer thi. Photosynthesis lab report is wholly free and included in the price that you pay. This experiment deals with measuring the amount of oxygen accumulated. It will totally ease you to look guide photosynthesis lab answer key as you such as. You should study the differences between C3, C4 and CAM plants. STUDY. a field 100 m by 100 m) of wheat can convert as much as 10,000 kg of carbon from carbon dioxide into the carbon of sugar in a year, giving a total yield of 25,000 kg of sugar per year. Click the Counter Tab on the Photosynthesis Lab **In addition to close-toed shoes, you are required to wear long pants or skirt (ankle length) to participate in this lab. The oxygen formation was measured by observing the leaf disks in water. Gen Bio 1 Lab #7: Cell Respiration & Photosynthesis PRE-LAB: Do all of the Pre-lab Vocabulary, Pre-Lab Reading, and Pre-lab Activities on pages 1-5 before coming to lab. photosynthesis-lab-answers 1/3 Downloaded from calendar. When measuring transpiration rates with a potometer, it is important to remember A small amount of water (~2%) is used in photosynthesis and to maintain the Design of an experiment to test hypotheses about the effect of temperature or  Bubbles are given off by the plant through Photosynthesis. Finding a reliable source of aquatic plants can prove With the Photosynthesis Lab Gizmo™, students can infer rates of photosynthesis by measuring oxygen production. Move the slider so that the light source is 130 mm from the Elodea. As photosynthesis proceeds, oxygen is released into the interior of the leaf, which changes the buoyancy- causing the disks to rise. The relationship between light intensity and the rate of photosynthesis in spinach leaves Words: 1266 Pages: 5 Exercise 10: Paper Chromatography of Photosynthetic Pigments Words: Pages: 0 Affects the Amount of Oxygen Created Through the Process of Photosynthesis by Hydrilla, Words: 1199 Pages: 5 photosynthesis is: 6 CO 2 + 6 H 2O + light energy à C 6H 12O 6 +6 O 2 Earlier you completed the investigative lab, Photo Finish. The concentration of CO2: Higher concentration of carbon dioxide helps in increasing the rate of photosynthesis. Write a detailed conclusion based on your results. 75 hours (2 Lab Periods)Kit Includes: Instructions, Sodium Biocarbonate (baking soda), liquid soap, plastic syringe (20 cc), transfer pipets, plastic cupsAll You Need: Leaves (i. Students can measure the rate over time. Select the BAR CHART tab. Quiz for AP Cellular Respiration Lab- students must earn at least a 70% in order to begin the lab. Measure the time taken for each disc to rise. 2 So we simply have to subtract the volume at 00:00:30 with the volume at 00:00:0o, so that change in volume The hypothesis regarding this experiment states that "if CO2 is added to the beaker, then the rate of photosynthesis will increase". 345 and IQR =0. L. Since cellular respiration is taking place at the same time and consuming oxygen, the rate that the disks rise is an indirect measurement of the net rate of photosynthesis. Nov 07, 2020 · In this virtual photosynthesis lab, students can manipulate the light intensity, light color, and distance from the light source. With this additional data, your graph should have five data points. In the Photosynthesis Lab Gizmo ™, you can monitor the rate of photosynthesis by measuring oxygen production. Include the following sections in your lab report, which should be typed. photosynthesis will be measured by counting the number of oxygen bubbles produced by 2 solutions of baking soda and water (one strong and one weak). Add a small amount of sodium bicarbonate to each test tube and shake gently. Remove several leaves Count the bubbles to measure the rate of photosynthesis. The photosynthesis process rate varies from different wavelengths and intensities of light. 398 at 0. The bubble rate can will be measured in the following way: 1. Nov 26, 2011 · Independent Research Leaf Disc Photosynthesis Lab 1. California Science Content Standards A by-product of photosynthesis is oxygen. The transfer of electrons during the light-dependent reactions of photosynthesis reduces DPIP, changing it from blue to colorless. Suppose that we have the following result: Rate of Photosynthesis Results: Time Volume in Gas Syringe (mL) 00:00:00 0. There are three ways to measure the rate of cellular respiration. Determining a method to measure the rate of photosynthesis was an outstanding question, but it was discovered that the rate can be determined either by measuring the consumption of carbon dioxide or the accumulation of oxygen (College Board 1997). However, The Effects Of Light On Photosynthesis Can Be Measured Indirectly. First Make a hypothesis about effect of the distance of sunlight from an elodea plant on the rate of photosynthesis. Designing an experiment to test the rate of photosynthesis. The tapered part (the point) should be 1 inch long. things we could measure. You measure the rate of photosynthesis by counting the number of bubbles in the jar every ten minutes. What was the name of the plant you used to study photosynthesis? elodea 2. Set the light intensity to the next value on your table and count the number of bubbles produced over 30 seconds using the clock. In this lab, the rate at which small leaf "disks" rise to a floating measure of the net production of oxygen produced by photosynthesis. In this experiment, you will use an O2 Gas Sensor to measure the amount of oxygen gas consumed or produced by a plant during respiration and photosynthesis. 1m from the light. With water, light energy from the sun, and carbon dioxide from the air, photosynthetic organisms are able to build simple sugars. That mean the rate of photosynthesis also decreases in this graph. 1964. Robert J. Acces PDF Photosynthesis Lab Answer Key Photosynthesis Lab Answer Key When somebody should go to the books stores, search initiation by shop, shelf by shelf, it is in fact problematic. CO2 levels, Oxygen levels, are the most common. Check your answers at the END of the quiz. Record this in. ^The data show … _ a. BSC 108 Lab 5 Photosynthesis Lab and Journal Worksheet (Alabama) Experiment 1 - Measuring the Rate of Photosynthesis Experiment 3 - Effect of Light Intensity Experiment 4 - Effect of Environment Temperature Instructions: Answer the questions below, based on Experiments 1, 3, and 4. 04 Temperature and fermentation rate - preparation All zipped. Oct 06, 2016 · Background and Pre-Lab Photosynthesis fuels ecosystems and replenishes the Earth's atmosphere with oxygen. What evidence do you have to support your answer? 27 Mar 2018 The rates of NOP and GOP are measured from the difference in O2/N2 (Grande et al. The average amount of CO 2 absorbed from the air in one hour on a bright day by a given sample of leaves can be determined when equal volumes of air are simultaneously passed over the green leaves in a chamber exposed to light and then through a solution of baryta of Site 2: Photolab → biol. Record the temperature of each solution and check it at intervals throughout the experiment. As the pigments that we just examined absorb light, electrons within photosystems are excited to a higher energy level. 88 Schools, New Ulm, MN 56073 based on "The floating leaf disk assay for Investigating photosynthesis" Summary. This is the experiment because the one of the two tested cup with have baking soda in it which is Sodium Bicarbonate, which will produce Carbon Dioxide, which is need for photosynthesis. Krebs cycle (Citric Acid cycle)- 6. Answer the lab question – What factors affect the rate of photosynthesis in plants? 4. 3 Determination of the light absorption spectrum of dye solutions. Access to ALL Gizmo lesson materials, including answer keys. Measuring cylinder, 20 cm3 All solutions used are low hazard – refer to relevant CLEAPSS Hazcards and Recipe cards for more information. 15. In photosynthesis, electrons are normally transferred to NADP+. Lab # 5 Plant Pigments and Photosynthesis Introduction In Lab 5, we separated plant pigments using chromatography and measured the rate of photosynthesis in isolated chloroplasts. Use MathJax to format equations. Decide how you will organize the table into columns and rows. The rate of photosynthesis depends on the level of carbon dioxide available. But there are some simple photosynthometers by which one can easily determine the amount of CO 2 absorbed at a given time during photosynthesis by In my hypothesis, I had predicted that photosynthesis rate will increase in the plant discs under the red and blue lights, causing an increase in the number of floating discs after the period of time of 10 minutes compared to other colors of light due to the fact that the pigments in a plant – chlorophyll a, chlorophyll b, and β-carotene Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a by-product. • study the compare the rates of photosynthesis for plants in different light conditions. Key words : Biomass, CO2 Fixation, Elevated CO2, Growth Analysis, Radish. To measure the formation of See full answer below. The experimental set-up involves a qualitative measurement of the CO 2 concentration in the vials. Anatomy of these plant cells, enzymes used to fix carbon, etc Study Measuring Oxygen Production Of Spinacea Oleracea Using An Oxygen Electrode 964 Words | 4 Pages. Temperature, light intensity, and CO 2 levels can be varied. 8. You already observed how light colors will affect the growth of a plant, in this simulation you can directly measure the rate of photosynthesis by counting the number of bubbles of oxygen that are released. One sits in direct sunlight, and the other sits in a dimly lit room. 10. 21 Apr 2018 Mrs Peers-Dent shows you how to measure the rate of photosynthesis of pondweed. Mar 13, 2007 · One of the classic ways is to measure the amount of carbon dioxide taken up and synthesised into glucose (or starch) but that required that the CO2 included radioactive Carbon 14 - its a fun experiment but not for the school lab! Basically photosynthesis takes CO2 and turns it into glucose so you will need a means of measuring the reduction in Group Size: For 10 lab groupsTime Required: Complete in 1. The equation for photosynthesis is: 6CO 2 + 6H 2 O -----light-----> C 6 H 12 O 6 + 6O 2 + H 2 O. Oxygen production is used to measure  The idea of this experiment is to measure the effect of light intensity and availability of carbon and their effects of the rate of photosynthesis. Match. edu Subject: Download Ap Biology Photosynthesis Lab Answers - AP Biology Photosynthesis Chapter 8 Reading Guide – ANSWER KEY 1 As a review, define the terms autotroph and heterotrophKeep in mind that plants have mitochondria and chloroplasts and do both cellular respiration and photosynthesis! Factors affecting photosynthesis. proposed a photosynthetic rate measurement method To date, the photosynthesis fluorescence characteristics of crops and  Photosynthesis involves converting light energy into chemical energy. Finally determine the rate of respiration and photosynthesis of a plant. The evidence for the rate of photosynthesis will be understood by measuring the Oxygen gas given off as a result of photosynthesis by using vernier oxygen sensor. Student Exploration: Photosynthesis Lab (answers) Photosynthesis Lab Answer Key Vocabulary: carbon dioxide, chlorophyll, glucose, limiting factor, nanometer, photosynthesis, wavelength Prior Knowledge Questions (Do these BEFORE using the Gizmo . When photosynthesis occurred, oxygen was produced in the leaves, causing them to rise in water. Aug 25, 2018 · Photosynthesis Virtual Lab Worksheet Answer Key and Physical Science Balancing Equations Worksheet Answers Image Worksheet August 25, 2018 We tried to locate some good of Photosynthesis Virtual Lab Worksheet Answer Key and Physical Science Balancing Equations Worksheet Answers Image image to suit your needs. As oxygen is produced, the density of the leaves change and they will begin floating in a sodium bicarbonate solution. That's why our Advanced Biology Through Inquiry lab manual provides tips for accurate data collection and analysis, editable labs for seamless integration into your individual curriculum, and consistent assessment to ensure that students are engaged and critically thinking throughout the activity. Count the number of beats in 30 seconds and multiply that number by 2. The rate of photosynthesis can be measured by: measuring O 2 production; measuring CO 2 consumption In this lab, students explore the process of photosynthesis in spinach leaves. , weigh them). 1. 2 hours ago · Photosynthesis SHORT ANSWER Experiment 1: Measuring the Rate of Photosynthesis Lab Results 1. There are plenty of methods available to measure photosynthesis. These include: the rate of oxygen. The timer in the square box can be used to measure 30 seconds. Move the BIO 102 - Lab 6 2. What are some ways that you can measure the rate of photosynthesis in our lab? Think about the products of the reaction. Cut a strip of filter paper 8 inches long and 1/2 inch wide, and taper the bottom end to a long point. Alternatively, they could explore how to measure the rate of photosynthesis using session, an oral presentation, or a traditional lab report. This virtual experiments require Adobe Flash Investigating the rate of photosynthesis. Describe how the functional units for beta carotene, xanthophyll, chlorophyll A, and chlorophyll B are different. Biology Lab Study Guide Population Carrying Capacity Ecology and Relationships Evolution and Ecology Processes that make ATP Mendelian Genetics Preview text Faster Rates of Photosynthesis in Spinach ( Spinacia Oleracea ) Leaves as Light Intensity Surges Abstract Photosynthesis is a food making process that autotrophic plants use. library. Write a testable hypothesis for your lab. Observe the  Videos and notes for AQA Biology A-level Required practical 08: Investigation into the effect of a named factor on the rate of dehydrogenase activity in extracts of . What do you think the bubbles are? _____ 2. Construct a graph of the rate of photosynthesis (mL/minute) on the y-axis versus the light intensity value (without units) on the x-axis. MEASURING THE RATE OF PHOTOSYNTHESIS . Using the information provided above and your knowledge of photosynthesis, answer the following questions. In this experiment, we will be using the same plant you examined in Lab 3 called Elodea. Created by. Like all enzyme-driven reactions, the rate of photosynthesis can be measured by either the disappearance of substrate, or the accumulation of products. Provide details and share your research! But avoid … Asking for help, clarification, or responding to other answers. Do you These two solutions can now be used to demonstrate both photosynthesis and of a Photosynthesis Experiment below so as not to bias their own creativity . This activity will allow you to measure the rate at which the photosynthesis process occurs. Why did the ACTIVITY 3. During photosynthesis, light energy is used to convert carbon into glucose (C 6 H 12 O 6), which is a simple sugar, or monosaccharide. Key words: photosynthesis, project-based design, middle school. At a temperature above 104 degrees Fahrenheit – 40 degrees Celsius – the enzymes that carry out photosynthesis lose their shape and functionality, and the photosynthetic rate declines rapidly. Students can work  Measuring the Photosynthesis Rate in Aquatic Plants - Elodea. Fill in the table below with the results from your first experiment. Use this site to answer questions about photosynthesis. Sep 22, 2014 · By measuring the rate at which these gases are exchanged, the rate of photosynthesis can be determined. How do the  Graph showing rate of photosynthesis and light intensity. 14. Dissolved oxygen can be measured directly to determine if aquatic plants undergo photosynthesis or cellular respiration in different conditions. Maybe you have knowledge that, people have look hundreds times for their favorite novels like this photosynthesis lab answers, but end up in Lab 10: DIY Measuring the Rate of Photosynthesis Part A: Discuss with your lab group to answer the following questions: 1. Diagram in link In my hypothesis, I had predicted that photosynthesis rate will increase in the plant discs under the red and blue lights, causing an increase in the number of floating discs after the period of time of 10 minutes compared to other colors of light due to the fact that the pigments in a plant – chlorophyll a, chlorophyll b, and β-carotene Download GIZMO PHOTOSYNTHESIS LAB ANSWER KEY PDF book pdf free download link or read online here in PDF. During my preliminary I attempted to measure different colours in order to gain an understanding on how the colour of light affects the rate of photosynthesis. Gravity. In a lab setting how would you be able to tell if photosynthesis was occurring in plant? b. Your team will use the leaf disk assay procedure to determine the rate of Label the plastic cups A, B, and C. Photosynthesis Lab Unit 2 Standard: HS-LS1-5 Use a model to illustrate how photosynthesis transforms light energy into stored chemical energy. output The portable LI-6400XT photosynthesis system is used to measure light response curves, temperature response curves and CO 2 response curves. Materials: Respiration chamber, A by-product of photosynthesis is oxygen. 6) List as many factors as possible that could affect the rate of photosynthesis. Learn. Measuring the Effect of CO2 on Photosynthesis in Spinach Leaves (Part 2) Aaima Amer Introduction Discussion How is photosynthesis affected by carbon dioxide? Research Question Background Photosynthesis is the process through which plants and other photosynthetic organisms use a way to calculate a rate of photosynthesis. Photosynthesis Lab: Floating Leaf Disks to Measure the Rate for Photosynthesis, 2016 . Photosynthesis Lab Gizmo : Lesson Info : ExploreLearning Photosynthesis gizmo answer key explore learning, Student exploration plate tectonics, Calorimetry gizmo work answers, Gizmo circuit Golf Range Gizmo Answers ExploreLearning ® is a Charlottesville, VA based company that develops online Photosynthesis Pre Lab Questions Joey Gramenzi 11/11/15 Period: 2 1. Making statements based on opinion; back them up with references or personal experience. B Factors Affecting Photosynthesis Lab · Rate  14 Oct 2014 In this lab, we'll see how we can set up an experiment to measure the rate of this important process. It should remain constant. NADPH in use a Colorimeter to measure color changes due to photosynthesis. 1) Set the thermometer at 25 ° C (room temperature) and the light intensity to 20. While you calculate your breathing rate, have your partner take your pulse. pdf - Photosynthesis Lab Answer This decrease of volume, as read from the scale printed on the pipet, will be measured as the rate of cellular respiration (Cell Respiration). AP BIOLOGY LAB: PHOTOSYNTHESIS (adapted from AP College Board Photosynthesis lab) Background and Pre-lab: Photosynthesis fuels ecosystems and replenishes the Earth’s atmosphere with oxygen. The quiz may be taken as many Photosynthesis And Respiration Pre Lab The rate of photosynthesis can be measured by looking at the formation of products or the consumption of reactants. What do you think the bubbles are? _____ Select the BAR CHART tab. Material and Methods: 1. A. Photosynthesis is the process by which plants and other organisms (i. Study photosynthesis in a variety of conditions. The student will measure the rate of photosynthesis as a function of the number of leaf disks that begin to float throughout the experiment while exposed to -To determine the net rate of photosynthesis, one could measure the production of O2 and consumption of CO2 Introduction Living systems require free energy and matter to maintain order, to grow, and to reproduce. Photosynthesis is the process of trapping light energy and converting it into forms of chemical energy that are then used to drive the building of carbohydrates. co/weedsim This simulation allows you to manipulate many variables. Flashcards. Use a CO2 Gas Sensor to measure the amount of carbon dioxide consumed or produced by a plant during respiration and photosynthesis. macromedia. Record this in Table 3. Lab 8: Determining the Rate of Photosynthesis in a Leaf. In the Photosynthesis Lab Gizmo™, you can monitor the rate of photosynthesis by measuring oxygen production Nov 19, 2019 · The rate of photosynthesis of Mauna Loa Supreme leaf. OXYGEN EVOLVED. However, DPIP will photosynthesis-lab-answers 1/3 Downloaded from calendar. In this experiment, the leaves will only rise to the surface when enough CO2 and light is present to allow the leaf disks to carry out photosynthesis and produce O2. The maximum rate of dye reduction is 0. Present your results in a graph. Table 3. photosynthesis is: 6 CO 2 + 6 H 2O + light energy à C 6H 12O 6 +6 O 2 Earlier you completed the investigative lab, Photo Finish. a. On the graph, notice the The relationship between ET50 and the rate of photosynthesis is that between each treatment, the ET50 is half of the given amount of Carbon Dioxide. 30. s question, experiment s using. Photosynthesis Lab. We tested things that affect the rate of photosynthesis such as the importance of carbon dioxide and the source of light emissions. 1985. 2% bicarbonate solution, how much baking soda would I need to add? Show work. Measurement can take up to 30 seconds to complete. Make sure the whole measurement area is occupied by leaf tissue. The role of light in photosynthesis can be investigated in several ways. While Identify the data that will be collected (this will be the pH that will be measured). Photosynthesis Lab . MEASURING THE RATE OF PHOTOSYNTHESIS Directly Quantifying The Rate Of Photosynthesis As Affected By The Absorption Of Light Can Be Die Cicult. 12. These high-energy electrons are essential to ATP production and reduction of NADP+ to NADPH. IntroductionThis lab has been created in order to find what extent does distance from a light source (5cm, 10cm, and 15cm) affect the rate of photosynthesis (measured in bubbles / 3 min) in Elodea water plants. Prepare different concentrations of sodium hydrogen carbonate solutions: 0%, 5%, 10% NaHCO3, in different beakers. The purpose of this lab was: to observe and analyze the effect of varying sodium bicarbonate levels, and therefore varying carbon dioxide levels, on the rate of photosynthesis; and to demonstrate how to study the rate of a chemical reaction by measuring the rate of accumulation of product (in this case oxygen). dioxide is a reactant that is used up during photosynthesis. 28. PART B: Student Practical Report. 7) What would be a potential problem with measuring the change in carbon dioxide levels to determine the rate of photosynthesis? Purpose: To measure the rate of CO 2 production in spinach leaves. If you are referring to the "Plant Pigments and Photosynthesis" Lab Then, the DPIP is used to substitute NADP+. Lab 5. com on November 13, 2020 by guest Read Online Photosynthesis Lab Answers Thank you very much for downloading photosynthesis lab answers. Photosynthesis process requires several factors such as: Light Intensity: Increased light intensity results in a higher rate of photosynthesis. Identify your hypothesis: (Example: if there is 3% (3g) CO 2 instead of only 1% (1g), then the leaf discs will rise faster because…) If: _____ ANSWER 1You can use a few things to measure the rate of photosynthesis. Make sure it is pushed down to the bottom of the test tube. Question: How Does Light Intensity Affect the Rate of Photosynthesis? Procedure: The purple slider can be used to change the light levels. ) [Note: The purpose of these questions is to activate Page 1/5 compare the rates of photosynthesis in different leaves. How do plants get energy? Developed by Chantier 7 project team If there is no answer from students, teachers can also ask students to write their answer on a Place a piece of elodea in each Study photosynthesis in a variety of conditions. Of course this technique is imperfect because of other influences on growth, the amount of time you have to wait to get a measurable change, and ideally you would want to use the dry mass of your plants to avoid water content differences, but you have opted to exclude the methods that Question 1 - How Does Light Intensity Affect the Rate of Photosynthesis 1. By measuring the rate at which the bubbles are produced it is possible to tell how fast the plant is  Click here to get an answer to your question ✍ The diagram below is an experiment conducted to study a factor necessary for photosynthesis. Measurement of photosynthesis in plant tissues using bicarbonate solutions. 065-1. As light intensity increases, the rate of photosynthesis initially increases and then levels off to a plateau. 2) Measure the rate of photosynthesis in isolated chloroplasts using the dye DPIP. Cut the tip of the The rate that the disks sink is an indirect measure of the rate of cellular respiration. The Start studying Elodea and Photosynthesis Lab. Lab 2: Photosynthesis (The Light Reactions) 124 PIGMENT IDENTIFICATION: PAPER CHROMATOGRAPHY (FLAMMABLE: ALL BUNSEN BURNERS IN THE LAB MUST BE OFF) PROCEDURE 1. My hypothesis is that  3 Dec 2016 The answer is yes, some of the oxygen will be used in the leaf's respiration process. ➢ Plot and interpret At the same time photosynthesis is occurring, respiration is also taking place. Photosynthesis Lab for AP biology where students use a sprig of elodea. In most of the photosynthetic experiments, the rate of photosynthesis is determined either by measuring the volume of OI 2 evolved per unit time or mg or ml of O 2 evolved as estimated by titration. Students can follow along with the directions found in their handout / lab report (see experimental design, steps 1-5 in sample lab report within the assessment section) The main focus of the investigation depends on Photosynthesis represented by the equation 6H 2 O + 6CO 2 → C 6 H 12 O 6 + 6O 2 is one of the most crucial chemical reactions on earth as it produces O 2 molecules– a gas vital to the survival of many organisms (Vidyasagar, 2018) This process takes place during the light dependent phase of photosynthesis and is indicated by the production of bubbles and can be used to analyse the rate of Mar 26, 2020 · To measure the rate of photosynthesis, place a sprig of elodea in a test tube next to a light source and calculate the number of air bubbles coming out of the plant. Aim: Photosynthesis is the process when green plants use sunlight to Using a stop watch, I will measure the amount of time it takes for 5 leafs to reach Answer the purpose of the experiment: What are the effects of light  Did the results confirm or reject your initial hypothesis? Why or why not? 2. Light intensity, carbon dioxide levels, temperature, and wavelength of light can all be varied. Determine which conditions are ideal for photosynthesis, and understand how limiting factors affect oxygen production. Photosynthesis Pre Lab Questions Joey Gramenzi 11/11/15 Period: 2 1. But there are some simple photosynthometers by which one can easily determine the amount of CO 2 absorbed at a given time during photosynthesis by Lab Answers AP Biology Lab - Photosynthesis Cellular Respiration Pre-Lab Quiz. The equation for photosynthesis is: 6CO 2 + 6H 2 O -----light-----> C 6 H 12 O 6 + 6O 2 Biology Coursework ¡V Does The Light Intensity Affect the Rate of Photosynthesis The Investigation In this experiment I will investigate the affect in which the light intensity will have on a plants photosynthesis process. You will measure CO 2 consumption in plant leaves using an Photosynthesis Gizmo Answers oxygen production. Observe the left pane closely. There are several ways of measuring the rate of photosynthesis in the laboratory. Chemical oxidation- 3. 19 Aug 2019 Students will write a lab report including, hypothesis, experimental design, technique that will be used to measure the rate of photosynthesis. B. was the hypothesis correct or incorrect; explain using the data Photosynthesis Lab Background The rate of photosynthesis can be measured in two different ways: the disappearance of substrate or the amount of products produced. Like all enzyme-driven reactions, the rate of photosynthesis can be measured by either the disappearance of substrate, or the accumulation of product. Dec 21, 2018 · A hands-on lab activity will enable students to assess the change in the rate of photosynthesis when CO 2 concentration changes. What happens to the oxygen that is produced as a result of photosynthesis? 7. • Identify As described earlier, the pH of the solutions will be low   6 Feb 2015 This experiment was conducted in order to see if the temperature of an plants are at a lower temperature, the rate of photosynthesis would be more The hypothesis was supported because the plants had a faster rate of. Photosynthesis Lab Answer Keythe rate of photosynthesis. In the process of photosynthesis, plants use light energy to combine carbon dioxide and water to form glucose. Repeat this 2 more times. . Hypothesis: The leaf disks placed in the water solution with sodium bicarbonate will float to the top faster and in a higher quantity because the sodium bicarbonate will serve as a source of carbon dioxide for The rate that the disks sink is an indirect measure of the rate of cellular respiration. One problem in measuring a rate of photosynthesis is that there is a competing process occurring at the same time, cellular respiration, a process that uses oxygen. Hypothesis: Yes, light intensity does affect the rate of photosynthesis. The lowest rate of dye reduction is 0. I. Measure out 10ml of aerated water and place it in test tube 1. Include a brief statement describing why you selected the graphing method you did. Students can compare the rate of photosynthesis in sun and shade plants and at different light intensities, amongst many other factors. Change lighting and availability of carbon dioxide to alter the rate of photosynthesis. c) be able to assemble the equipment needed to measure the rate of photosynthesis of a chosen plant e. Rates describe how measurable quantities change over time. A standard lab centrifuge was used to spin down the chloroplasts (Clifton NE 010GT/I) at 2650 RPM,  There are several ways of measuring the rate of photosynthesis in the lab . Propose hypotheses on how each of these variables effect the production of oxygen from a plant. But how can we measure the rates at which photosynthesis takes place? The quantities are mind boggling. Bioscience, 14 // Provide alternate content for browsers that do not support scripting // or for those that have scripting disabled. output I want to measure photosynthesis rate of a wheat ear by IRGA. You will use DPIP, a blue compound, as an electron acceptor. A by-product of photosynthesis is oxygen, which is released. Glycolysis- 4. To improve results, add a pinch of baking soda to the water in the test tube. To accurately measure photosynthesis and transpiration sophisticated instruments such as LiCOR 6800, CI340 and CIRAS-3 are available which are portable and very useful in field measurements Measuring The Rate Of Photosynthesis Using A Spectrophotometer and other kinds of academic papers in our essays database at Many Essays. As oxygen gas is a product of photosynthesis, the rate of photosynthesis in a leaf can be determined by measuring the amount of oxygen the leaf produces in a certain period of time. Respiration rates differ by the amount of activity and/or development the organism is going through. 2. 2 Jun 2019 study photosynthesis in an aquatic plant (Elodea) We can measure the rate of photosynthesis and Create a hypothesis for this experiment. Rate of A photosynthesis rate can be calculated by measuring how much investigation is to develop the most valid or acceptable answer to the research question! Place all the beakers on the overhead projector. 26 Mar 2019 Measuring Photosynthesis. einstein™Tablet with MiLAB or  15 Jun 2016 Students should be able to describe the process of photosynthesis, including and carbon dioxide concentration on the rate of photosynthesis all need to other 5 questions that should be answered without using the resource is the classic factors affecting photosynthesis experiment, these sheets could  24 Feb 2015 Lab 07 Carbon Dioxide Coupling in Chloroplasts: Students measure the effect of increases the rate of NADPH and ATP supply (and thus oxygen experiment proving the Chemi-Osmotic Hypothesis of bioenergetics. The thylakoid membranes of the chloroplasts are mechanically disrupted so that the natural electron transport chain no longer functions normally. Since the middle of the 19th century, the level of carbon A brief outline of various ways to measure the rate of photosynthesis - including There are a few key methods to calculate the rate of photosynthesis. Oct 02, 2008 · This is my procedure to investigate the effect of light intensity, carbon dioxide concentration and temperature in Elodea (a pondweed): 1. You will count the number of bubbles at each level. Introduction. CO 2 + 2KOH —> K 2 CO 3 +H 2 O. On the graph, notice the Aquatic plants undergo photosynthesis and cellular respiration much like terrestrial plants. How can the rate of photosynthesis be measured? You measure the amount of oxygen produced, or the amount of carbon dioxide used. With the Photosynthesis Lab Gizmo™, students can infer rates of photosynthesis by measuring oxygen production. Photosynthesis Lab Gizmo : Lesson Page 18/26 The Term Paper on Photosynthesis Lab Report. Did the Elodea consume or release CO 2 Title [MOBI] Ap Biology Photosynthesis Lab Answers Author: oak. Page 1 of 8 [email protected][email protected] Nov 02, 2014 · The rate of photosynthesis for the first variable was 1 minute and the rate of photosynthesis for the second variable was at 4 minutes. • Create hypotheses about the effects of environmental variables on the rate of photosynthesis. 32 Using the floating disk technique in our experiment to measure the rate of photosynthesis, spinach leaves will be submerged in a concentration of CO2 and a concentration of water. Repeat until you've tried each To adjust for this, use the inverse, $\frac {1} {ET_{50}}$, for comparing the rate across conditions. A plant is shown in a beaker and test tube which bubbles to indicate the rate of photosynthesis. Press start and record the bubbles per minute for each of the following light distances. Using the floating leaf disk assay protocol as a tool to measure the rate of photosynthesis, design an experiment to investigate how varying an environmental or plant condition effects the rate of photosynthesis. lab report writing There are a you require several plants so that you have replicate measurements and you  We can measure rates of photosynthesis in several ways, all of which come it describes what you will see or measure in your experiment if your hypothesis is. The Measurement of CO 2 Uptake:. Chemical reduction- 2. How would you improve this experiment?Lab 20: Energy and Photosynthesis Pre-Lab Questions 1. The blood The diagram shows the way the experiment was set up. There are several ways of measuring the rate of photosynthesis in the lab. 8 00:01:00 9. In this experiment, a blue dye (2,6-dichlorophenol-indophenol, or DPIP) will be used to replace. Therefore as more disks begin to float the time it takes for 50 percent of them to float decreases. , Considering the light-limited part of the experiment, Figure 4 used to demonstrate the method and to determine several key parameters  slower rates of photosynthesis This experiment could influence The hypothesis of the lab was if the Elodea is placed farther from the light source, then it would  Students use a carbon dioxide sensor to measure the rates of photosynthesis and respiration in spinach leaves. photosynthesis in plants for the remainder of the lab. In the blank portion of this paper, draw the picture which shows the overall process of photosynthesis. M. g. Read online GIZMO PHOTOSYNTHESIS LAB ANSWER KEY PDF book pdf free download link book now. In the Photosynthesis Lab Gizmo™, you can monitor the rate of photosynthesis by measuring oxygen production. The purpose of this lab was to measure the rate of cellular respiration. It is the simplest method. On the other hand, low light intensity results in a lower rate of photosynthesis. Put sprig if Elodea in each test tube, cut end up. Changes in the levels  In reactions like photosynthesis and respiration it is often easiest to measure The rate of photosynthesis may also change in the same plant as tissue ages. Remembering (2 pts) What is the purpose of an experimental control? 3. the fastest. oleracea using an oxygen electrode in response to varying light intensity and the effect of Diuron on rate of photosynthesis Introduction Photosynthesis is a fundamental process that utilises light to produce energy. “The data show …” a. Record your hypothesis above your data table. One of the materials that plants use in photosynthesis is carbon dioxide. Photosynthesis SHORT ANSWER Experiment 1: Measuring the Rate of Photosynthesis Lab Results 1. e. Then it boosts them to a _____level. Instructions and answers for teachers & technicians Before carrying out any experiment or demonstration based on this guidance, it is the responsibility To measure the rate of photosynthesis by the production of oxygen in aquatic plants. The variables to be examined in relation to carbon dioxide use are the amount Firstly, this lab did not measure the rate of photosynthesis as DCPIP blocked the procedure from occurring early on, so claiming that this lab measured the rate of photosynthesis does not make sense and we should focus on the fact that we are only observing and assessing the first steps of photosynthesis. CO 2 Levels: Increasing the level of CO 2 stimulates photosynthesis until the rate reaches a plateau. Photosynthetic activity can be measured by the amount of sugar or oxygen produced in the cells or tissues of Questions (answer in your lab notebook):. We showed that rice leaves achieved maximum photosynthetic rates Answers and further research questions arising from the FPM technique. The transfer of electrons during the light-dependent reactions of photosynthesis reduces DPIP, changing it from blue to colorless Thanks for contributing an answer to Biology Stack Exchange! Please be sure to answer the question. Most of the organisms familiar to us depend on the process of photosynthesis for two fundamental reasons: 1) photosynthesis fixes carbon to create larger organic molecules, and 2) this process releases oxygen into the environment. 3m from the light and the minimum rate of dye reduction is 0. A photosynthesis rate can be calculated by measuring how much CO 2 a plant consumes or how much O 2 a plant produces over time using the following equation: Photosynthesis rate = change in CO 2 or O level time To measure how much CO 2 spinach consumes (or O 2 it produces) over time, simply put five 5. Describe a technique for measuring photosynthetic rate. (i). The vast majority of living Lab 07 Carbon Dioxide Coupling in Chloroplasts: Students measure the effect of providing carbon dioxide on oxygen production of isolated chloroplasts, to determine whether ATP and NADPH utilization in the C3 pathway increases the rate of NADPH and ATP supply (and thus oxygen production) in intact chloroplasts. As oxygen is produced Key Concepts: • Photosynthesis is comparing the rate of photosynthesis in different light intensities -including in the dark- by viewing the  needed for a photoautotroph to perform photosynthesis: Carbon dioxide, water, and light. Key concepts: Reduce The How can you measure the rate of photosynthesis in pond weed? Measure In this experiment, what is the independent variable? Answer to Experiment 3: Measuring the Rate of Photosynthesis with Floating Leaf Discs Post-Lab Questions Present your results in a Answer to Experiment 1: Measuring the Rate of Photosynthesis Lab Results What was the name of the plant you used to study photosyn In this lab, students explore the process of photosynthesis in spinach leaves. From the given information, the hypothesis was that the optimal reaction rate was expected to be at the wavelength near 450 nm and 650 nm. Can you think of a way to how you might measure the gross rate of photosynthesis with this technique?Print and Web Resources: Wickliff, J. If the rate of photosynthesis increases, the rate of oxygen production goes up, and the rate of CO 2 consumption rises too! If the rate of photosynthesis goes down, then we can expect the opposite Photosynthesis involves converting light energy into chemical energy. The rates of these reactions can be increased somewhat by increasing the carbon dioxide concentration. Read and follow the directions on how to use this lab simulator. Photosynthesis Virtual Lab #2 - Measuring the Rate of Photosynthesis in Elodea. Cut elodea stems at an angle and use your fingers to crush the end of the stem. The baking soda will also provide the leaf with the carbon dioxide that it needs for photosynthesis. The greater the light intensity, the faster the rate of photosynthesis. In this activity you will measure the rate of electron excitation when light hits chlorophyll. Amount of water, which is going to be the reaction medium, in the Aug 19, 2019 · The teacher will now demonstrate to students the basic technique that will be used to measure the rate of photosynthesis. Did the rate of photosynthesis increase or decrease due to the independent variable? b. separate plant pigments using chromatography, and 2. Be sure the CO2 Gas Sensor is connected to the Vernier Lab Pro interface and that Lab Pro is In your groups use your answers to prelab questions 5 and 6 to test two  (iii) One student concluded that the rate of photosynthesis was inversely proportional to the distance of You should use information from the scientists' graph in your answer. Increasing temperature will [ increase / decrease ] rate of photosynthesis. The object of this lab was to see how photosynthesis and the light reactions in photosynthesis occur with different amounts of light. com/pub/shockwave/cabs/flash/swflash Study Guide Quiz 6 BIOL 101 Enzyme Lab Final Biology Lab Mollusk Essay Bio lab outline Bio Photosynthesis Lab Report draft 1 Exam3Spring 2015 Sample KEY Preview text Photosynthesis Lab Report (FINAL) Aaron Chen BIOL 101L-433 TA Daniela Munoz UNC Honor Pledge: I certify that no unauthorized assistance has been received or given in the completion The rate of photosynthesis is measured by one of the following methods: By measuring (I) the volume of CO, consumed (2) volume of oxygen liberated (3) amount of carbohydrate accumulated. • Identify another variable that might affect photosynthesis and design an experiment that uses leaf disks to test your ideas. com on November 11, 2020 by guest [MOBI] Photosynthesis Lab Answers When somebody should go to the ebook stores, search opening by shop, shelf by shelf, it is really problematic. Photosynthesis Lab Gizmo : Lesson Info : ExploreLearning A by-product of photosynthesis is oxygen. 3 Describe how you might extend this practical to investigate the effect of light intensity on the light-dependent reactions of photosynthesis. The Rate of Photosynthesis. Three factors that affect the rate of photosynthesis are temperature, light intensity, and the availability of water. This lab will evaluate the optimal wavelengths and degrees of intensity during photosynthesis when chloroplast is exposed to light. “The hypothesis was…” a. Design an experiment to test your hypothesis. Why is photosynthesis also important for people and animals? Virtual Lab #1: Measuring the Rate of Photosynthesis of Elodea from the University of Reading Oct 19, 2015 · We found that the amount of carbon affects the rate of photosynthesis. Average the 3 trials to get your average heart rate. pridesource. Formation of Acetyl CoA- 5. Other ways to measure photosynthesis are: 1 Sep 02, 2019 · The rate that the disks sink is an indirect measure of the rate of cellular respiration. There-fore, photosynthesis could not occur. In the . The rate of photosynthesis varies directly with air temperature. This experiment will look at the affect of light intensity on the rate of photosynthesis on Elodea Time is the independent variable and will be measured with a stop watch. LAB FOUR PLANT PIGMENTS AND PHOTOSYNTHESIS OVERVIEW In this lab you will: 1. Test. Investigating Photosynthesis with Algae Balls Pre-Lab Questions (10 possible points) Directions: After reading through the introduction and protocol for the Algae Ball lab, answer the questions below. Leaves usually contain CO2 and O2 and Click Take Measurement or New Measurement Answer the two questions, then click Measure. Summarize the process of photosynthesis. The objective of this experiment is to measure the rate of photosynthesis Hypothesis: The petri dish that is exposed to the most light and with the NaHCO3 solution will have the best results and the petri dish that is kept in the dark will have the poorest results. <img id="image_alive" ></img> <object classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" codebase="http://download. If you harvest Answered by Audrey C. 536 milligrams of carbon has been assimilated. to constant weight and weighed - this is repeated over the duration of the experiment. Lab: Exploring the Rate of Photosynthesis Photosynthesis is the process by which plants take carbon dioxide from the atmosphere, add water, and use the energy of sunlight to produce sugar. 5 x 0. Before coming to lab: 1) Use your textbook to review chloroplast structure and photosynthesis; The measure of O2 production gives us a means of measuring te amount of carbon bound in organic compounds; for each milliliter of oxygen produced, . Before attempting this exercise you should have a thorough understanding of the material in the topic Eukaryotes: Plant Cells. 8 00:02:00 18. This process will pull gases out of the leaf disks and cause them to sink in solution. Measuring the rate of photosynthesis? 3. Pre-lab Homework Lab 6: Photosynthesis & Cellular Respiration After reading over the lab and the topics of photosynthesis and cellular respiration from your textbook, answer these questions to be turned in at the beginning of the lab! 1. photosynthesis, you must keep one variable constant while manipulating the other variable. The plant I usually use for this experiment is called elodea, which is available at any local pet store in the fish area. Your answers will be recorded on paper, not electronically. Answers. Learn vocabulary, terms, and more with flashcards, games, and other study tools. This is an example of a common experiment used to investigate light intensity and the rate of photosynthesis. The transfer of electrons during the light-dependent reactions of photosynthesis reduces DPIP, changing it from blue to colorless Introduce students to photosynthesis with fresh water algae. 6 00:00:30 4. 6. Photosynthesis Occurs in Two Phases Within chloroplasts Photosynthesis powers 99% of Earth’s ecosystems; it is through the photosynthetic activities of plants, algae, and certain bacteria Measuring Heart Rate: 1. You may  14 May 2018 Dependent Variables Rate of Photosynthesis/ Number of Oxygen Bubbles The rate of photosynthesis is measured by the counting of number of  19 May 2014 B. How will we measure the rate of photosynthesis in this lab (give more details than #2)? 6. Recall chemical equations like that from last week’s lab: This week's lab covers the metabolic processes Purpose: The purpose of the Spinach Leaf photosynthesis is to measure the amount of how many leafs will go through photosynthesis in water. Experiment 3: Measuring the Rate of Photosynthesis with Floating Leaf Discs. Photosynthesis Gizmo Answers - Exam Answers Free We also have many ebooks and user guide is also related with explore learning gizmo answer key photosynthesis lab PDF, include : Expression And can directly measure the rate of photosynthesis by counting the number of bubbles of oxygen that are released. The Initial Exer- Photosynthetic Pigments Cises In Today's Lab Determined Which Wavelengths Of Light Were Most Readily The process of photosynthesis occurs in a series of enzyme-mediated steps that capture light energy to build energy-rich carbohydrates. Press the green button This page requires Flash Player version 10. 13. The bubbles are a product of photosynthesis as the oxygen is released and causes a bubble to rise to the top. Oxygen production is used to measure the rate of photosynthesis. Write the measurement down, then repeat 2-3 days later. In the first part of lab you will explore how photosynthesis varies with light intensity in leaves of your plant species. Can you think of a way to how you might measure the gross rate of photosynthesis with this technique? Print and Web Resources: ! Steucek, Guy L. 28 = -0. The floating disk assay provides a way to indirectly measure the rate of photosynthesis. Photosynthesis I: An Assay Utilizing Leaf Disks. 355. PART 2: In the _____reactions of photosynthesis, light _____electrons in chlorophyll and other pigments. In this lab you were introduced to a technique called the floating disk assay. Hill and Class/Summer 1982. Students punch out small discs from leaves, and float them in a syringe of sodium hydrogen carbonate solution. D. Click Start 4. Three things in the plant’s environment affect the rate of photosynthesis: Light Intensity: this is one of the most important factors. • Always  The hypothesis is that if plant disks are exposed to CO2 , water and light during the photosynthesis process, then the disks will form oxygen as a by-produce and   In this lab, we will study the effect of light intensity and quality (wave length As a measure of the rate of photosynthesis, we will monitor the rate of oxygen production. Suppose you are investigating photosynthesis in two elodea plants. These high energy electrons Dec 28, 2019 · c. The FLDA measures the net rate of Floating C3 Spinach Discs Lab Concerning Photosynthesis that Determined how Light Intensity Affects the Net Rate of Photosynthesis By Senegar & Mitchell and written by Sandra Monreal Abstract Researchers realize that spinach discs float normally so when infiltrating these discs The greater the light intensity the faster the rate of photosynthesis. The variables to be examined in relation to carbon dioxide use LAB QUIZ: Write down your answers as you take the quiz. SAMPLE ANSWER: No. On the graph, notice the Oxygen production bar. Analysis of the effects of light intensity on rate of photosynthesis using In this experiment, we used spinach leaf chads to see the effects of different the same time, consuming oxygen, the rate that the disks rise is an indirect measurement of   Design an experiment to test how light affects photosynthetic rates. Photosynthesis - Photosynthesis - Carbon dioxide: Included among the rate-limiting steps of the dark stage of photosynthesis are the chemical reactions by which organic compounds are formed by using carbon dioxide as a carbon source. As the rate of photosynthesis goes up the ET50 goes down. Exploration Photosynthesis Lab Gizmo Answer Key A by-product of photosynthesis is oxygen. This is why we provide the books compilations in this website. 9. The reaction rate of photosynthesis varies with light intensity, and as the light intensity increases the reaction rate also increases only up to a certain point (Advanced Biology for You, 2001). According to the data of the above graph, Q1=0. The formula for We can also measure the rate of photosynthesis by measuring an increase in the plant's biomass (weight). The formula for photosynthesis is the following: 6C0 2 + 6H 2 O -- (light energy) --> C 6 H12O 6 + 6O 2 If we take a look at the different components of the equation, we can quickly determine a few ways of measuring the rate of photosynthesis. It this case, number of bubbles of oxygen are counted given out in unit time by green aquatic plants like Hydrilla. Photosynthesis occurs in the chloroplast, an organelle in plant cells that contains the molecule chlorophyll. ǽA very basic and (1995) also measured the rates of photosynthesis in the whole plants were conducted in each experiment to check the rate of CO2 exchange   Purpose: To measure the rate of CO2 production in spinach leaves. 20 Feb 2020 The multi-factorial experiment was designed to obtain the multi-slice mechanism characteristic analysis has become a key problem to be solved in facility agriculture. Compare experimental results to control groups! 5. For every 15s in the virtual lab, when there was a low amount of carbon dioxide, only 3 bubbles rose, while the high amount of carbon dioxide caused 4 bubbles. Before coming to lab: 1) Use your textbook to review chloroplast structure and photosynthesis; 2) Read this handout - there may be a quiz. If your plant is in a pot, start your measurement at the base of the pot. Make sure it is not over a thick leaf vein or other odd textures. Use the link below to perform a virtual photosynthesis experiment. (circle below) a) Increasing the light intensity will [ increase / decrease ] rate of photosynthesis. You will not be allowed in the lab without these minimum requirements. 1) Plants use photosynthesis to make VIRTUAL LAB #1 - Measuring the Rate of Photosynthesis in Elodea. In this experiment, a light is  1 Objectives; 2 Lab 5 Overview; 3 Photosynthesis: Background; 4 Measuring the Rate of One could view the leaf as natural selection's answer to this problem. Figure 1 All solutions should be free of bubbles. 4. Since photosynthesis is a chemical reaction, its levels are monitored by the rate of occurrence. In the first experiment, we will be using the same plant you examined in Lab 3 called Elodea. measuring the rate of photosynthesis lab answers

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# Math Help - Power Series Question

1. ## Power Series Question

Power series from 1 to infinity of (n^n)*x^n? I applied the ratio test:
((n+1)^(n+1)x^(n+1))/((n^n)*x^n) = ((n+1)^(n+1)*x)/(n^n) and after taking the limit of n->infinity I got nx which goe s to infinity. I think I messed up, any help?

2. Hello, thehollow89!

The algebra of the Ratio Test is very tricky . . .

$\sum^{\infty}_{n=1} n^nx^n$

We have: . $R \;=\;\frac{a_{n+1}}{a_n} \;=\;\frac{(n+1)^{n+1}x^{n+1}} {n^nx^n} \;=\;\frac{(n+1)(n+1)^n}{n^n}\,x
$

. . . . . . . . . $= \;(n+1)\left(\frac{n+1}{n}\right)^n\!\!x \;=\;(n+1)\left(1 + \frac{1}{n}\right)^n\!\!x$

$\text{Take the limit: }\:\lim_{n\to\infty}\left[(n+1)\left(1 + \frac{1}{n}\right)^n x\right]$

. . . . . . . . $=\;\underbrace{\left[\lim_{n\to\infty}(n+1)\right]}_{\text{This is }\infty}\cdot\underbrace{\left[\lim_{n\to\infty}\left(1 + \frac{1}{n}\right)^n\,\right]}_{\text{This is }e}\cdot x$

. . . . . . . . $=\;\; \infty\cdot e\cdot x \;\;=\;\;\infty\quad\hdots\quad\text{The series diverges.}$

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# If $\lim_{n\rightarrow\infty} \frac{a_n}{b_n} = 0$ and $\sum_{n=0}^\infty b_n$ is convergent. Proving that $\sum_{n=0}^\infty a_n$ is also convergent

Prove that if $a_n \geq 0, b_n > 0$ for $n \in \mathbb{N}$ , $\sum_{n=0}^\infty b_n$ is convergent and $\lim_{n\rightarrow\infty} \frac{a_n}{b_n} = 0$ then $\sum_{n=0}^\infty a_n$ is also convergent.

What I did was let $\sum_{n=0}^\infty a_n$ be divergent then $\lim_{n\rightarrow\infty} \frac{a_n}{b_n} = 0$ is true if $\lim_{n\rightarrow\infty}b_n = \infty$ which is false, because $\sum_{n=0}^\infty b_n$ is convergent, SO $\lim_{n\rightarrow\infty} a_n$ = 0 which is a contradiction to $\sum_{n=0}^\infty a_n$ being divergent.

My question: Is this correct and if not how can I fix it or solve the problem some other way?

• No, it doesn't look correct. The series $\;\sum a_n\;$ can be divergent and still $\;\lim b_n=0\;$ (example?) – DonAntonio Apr 17 '18 at 18:37
• This is just a special case of the limit comparison test: en.wikipedia.org/wiki/Limit_comparison_test – Umberto P. Apr 17 '18 at 18:39

We cannot assume that $\displaystyle\sum a_{n}$ is convergent.
Rather, $\displaystyle\sum a_{n}=\sum\dfrac{a_{n}}{b_{n}}\cdot b_{n}$, and $\dfrac{a_{n}}{b_{n}}<1$ for large $n$, and hence $\dfrac{a_{n}}{b_{n}}\cdot b_{n}<b_{n}$ and $\displaystyle\sum b_{n}<\infty$.
Exists $\;N\in\Bbb N\;$ such that for all $\;n>N\;$ we have
$$\frac{a_n}{b_n}<1\implies\ldots$$


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# One "mol" of an ideal gas, initially at "300 K", is cooled at constant "V" so that "P"_f is 1/4 "P"_i. Then the gas expands at constant "P" until it reaches "T"_i again. What is the work w done on the gas?

Dec 30, 2015

DISCLAIMER: Yes, this will be long!

This is one of those problems where drawing a "P-V diagram" would really help. Let's see approximately what that looks like for this problem.

We know that:

STEP 1
${T}_{i} = \text{300 K}$

${T}_{i} \downarrow \implies {T}_{f}$ such that:
${P}_{f} \downarrow \implies {P}_{i} \text{/} 4$
$\Delta V = 0$

STEP 2
${T}_{i} = \text{previous } {T}_{f}$
${V}_{i} = \text{previous } {V}_{i}$

${V}_{i} \uparrow \implies {V}_{f}$ such that:
${T}_{f} \uparrow \implies {T}_{i} = \text{300 K}$
$\Delta P = 0$

From that, we construct the PV-diagram as follows:

Notice how we have the possibility for a reversible work process that accomplishes the same thing more efficiently.

TWO-STEP PATH: STEP 1

We should know that inexact differential work $\partial w = - P \mathrm{dV}$ when expanding or compressing a gas, and that the inexact differential heat flow $\partial q$ is not $0$.

STEP 1: WORK

We can then proceed by noting that $\Delta V = 0$. Thus, any expansion/compression work is $0$:

$\textcolor{b l u e}{{w}_{1}} = - \int P \mathrm{dV} = \textcolor{b l u e}{0}$

STEP 1: HEAT FLOW

Since PV-work didn't happen here, it was all heat flow, conducting out through the surfaces of the container, slowly leading the gas particles to redistribute more loosely without changing in volume, thus naturally cooling the gas.

In other words, the change in internal energy was all due to heat flow at a constant volume ${q}_{V}$:

color(blue)(DeltaU = q_V = ???)

Unfortunately we don't know enough to determine ${q}_{V}$. Had we known whether the gas was monatomic, diatomic linear, or what have you, we could determine its degrees of freedom and write ${C}_{V}$ or ${C}_{p}$ in terms of the universal gas constant $R$, since basically:

\mathbf(DeltaU = q_V

$\setminus m a t h b f \left(= {\int}_{{T}_{1}}^{{T}_{2}} {C}_{v} \mathrm{dT}\right)$

Either way, this release of thermal energy means that the first work step was inefficient; thermal energy escaped the container while the work ${w}_{1}$ was being done.

TWO-STEP PATH: STEP 2

Okay, so what's ${w}_{2}$ then?

STEP 2: WORK

${w}_{2} = - \int P \mathrm{dV}$

$P$ is constant here, but the volume DOES change, so:

$\textcolor{g r e e n}{{w}_{2}} = - P {\int}_{{V}_{i}}^{{V}_{f}} \mathrm{dV}$

$= - P \left({V}_{f} - {V}_{i}\right)$

We don't know how the volume changed, but using the ideal gas law, we can fidget with this:

$= - \cancel{P} \left(\frac{n R {T}_{f}}{\cancel{P}} - \frac{n R {T}_{i}}{\cancel{P}}\right)$

$= \textcolor{g r e e n}{- n R \left({T}_{f} - {T}_{i}\right)}$

STEP 2: TEMPERATURE

Alright, so we know ${T}_{f} = \text{300 K}$ in step 2. What's ${T}_{i}$ in step 2? Well, we can use what we knew from step 1. With a constant volume in step 1:

$P V = n R T$

${P}_{i} {\cancel{{V}_{i}}}^{\text{constant") = cancel(nR)^("constant}} {T}_{i}$

${P}_{f} {\cancel{{V}_{i}}}^{\text{constant") = cancel(nR)^("constant}} {T}_{f}$

${P}_{i} / {T}_{i} = {P}_{f} / {T}_{f}$

The temperature from step 1 we want is ${T}_{f}$, which is ${T}_{i}$ in step 2, so:

${T}_{f} = \frac{{P}_{f}}{{P}_{i}} \times {T}_{i} = \frac{1}{4} \times 300 = \textcolor{g r e e n}{\text{75 K}}$

Thus, in step 2, the gas heated from ${T}_{i} = \text{75 K}$ to ${T}_{f} = \text{300 K}$. Finally, we're getting a value! So, with $R = \text{8.314472 J/mol"cdot"K}$:

$\textcolor{b l u e}{{w}_{2} = - \text{1870.76 J}}$

In expansion work, work is done by the gas, so it should be negative.

REVERSIBLE WORK PATH

Now, if we try that reversible path, we assume that steps 1 and 2 aren't there and that this is an efficient path where the gas is acted upon very slowly so that it has time to adjust. We know that in this path, $\Delta T = 0$, but $P$ and $V$ change. So:

REVERSIBLE WORK PATH: WORK

${w}_{\text{rev}} = - \int P \mathrm{dV}$

$= - \int \frac{n R T}{V} \mathrm{dV}$

$T$ is actually constant this time, so...

$\textcolor{g r e e n}{{w}_{\text{rev}}} = - n R T {\int}_{{V}_{i}}^{{V}_{f}} \frac{1}{V} \mathrm{dV}$

$= \textcolor{g r e e n}{- n R T \ln | \frac{{V}_{f}}{{V}_{i}} |}$

Notice how the negative natural logarithm approximates the shape of the reversible path.

REVERSIBLE WORK PATH: VOLUME

Okay, but how did the volume change? Inversely proportionally to the pressure! The volume increased at a constant temperature, so the pressure should decrease.

Using the same trick with the ideal gas law as before:

$\textcolor{g r e e n}{{w}_{\text{rev}}} = - n R T \ln | \frac{\frac{\cancel{n R T}}{P} _ f}{\frac{\cancel{n R T}}{P} _ i} |$

$= - n R T \ln | \frac{{P}_{i}}{{P}_{f}} |$

$= - n R T \ln | \frac{{P}_{i}}{\frac{1}{4} {P}_{i}} |$

$= \textcolor{g r e e n}{- n R T \ln 4}$

So, with $R = \text{8.314472 J/mol"cdot"K}$:

$\textcolor{b l u e}{{w}_{\text{rev" = -"3457.89 J}}}$

In expansion work, work is done by the gas, so it should be negative.


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# Tag Info

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According to Theorem 5.13 in Rudin's "Principles of mathematical analysis" (slightly restated) If $f$ and $h$ are real and differentiable in $(0,1)$ and if $h'(x)\neq 0$ in a neighborhood of $1$, and $h(x)\to +\infty$ as $x\to 1^-$, and in addition $f'(x)/h'(x)\to A$ as $x\to 1^-$, then $f(x)/h(x)\to A$ as $x\to 1^-$. Applying this to $$f(x)=\... 0 One way to express this integral as a function of the Elliptic Integral K, is as follows. Do the change of variables x^2 = \frac{x_0+^2}{1-t^2}. This converts the integral into :$$ \frac{1}{\sqrt{x_+^2-x_-^2}}\int_0^1 \frac{dt}{\sqrt{(1-t^2)(1+\frac{x_-^2}{x_+^2-x_-^2}t^2)}} $$Which can be written formally as \frac{1}{\sqrt{x_+^2-x_-^2}}K(-\frac{x_-^2}{... 0 If$$f_h=\frac{1}{\sqrt{2 \pi \sigma ^2}}e^{-\frac{x^2}{2 \sigma ^2}}\qquad \text{and}\qquad f_\rho=\frac{f_h\left(\sqrt{\frac{x}{\rho }}\right)}{\sqrt{\rho x}}$$then$$f_\rho=\frac{e^{-\frac{x}{2 \rho \sigma ^2}}}{\sqrt{2 \pi \rho \sigma ^2} \sqrt{ x}}$$Let$$t^2=\frac{x}{2 \rho \sigma ^2}\implies x=2 \rho \sigma ^2 t^2\implies dx=4 \rho \sigma ^...

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By using the comparison test, we know that if we integrate a rational function $\int_a^{\infty} p(x)/q(x)dx$ such that $q(x)\neq 0$ on the interval, then we converge if and only if $\deg(p)-\deg(q)<-1$. However, actually combining and simplifying the rational functions in this problem is tedious algebra, so one can ask if there is a better way. In fact, ...

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I have finally managed to answer the question :) It is trivial to see that the integral is divergent for $r = 0\$, so let $r \neq 0$. If $r \neq 0$, note that we can always choose $a$ large enough such that $$\int^{\infty}_1 (\frac r {x + 1} - \frac {3x} {2x^2 + r})\ \mathrm {d}x = \int^a_1 (\frac r {x + 1} - \frac {3x} {2x^2 + r})\ \mathrm {d}x + \int^{\... 1 Try to bring the logarithms together! :)$$\lim_{a\to \infty} \biggl(r\ln\frac{a+1}{2}+\frac 3 4\ln|\frac{2+r}{2a^2+r}|\biggl)$$You maybe should take r < -2 and r > -2 because of the absolute value, but it gives the same result so I'll go with normal brackets.$$\lim_{a\to \infty} (\ln(\frac{a+1}{2})^r+ \ln(\frac{2+r}{2a^2+r})^\frac 3 4 )\...

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$\newcommand{\S}{\operatorname{sinc}}$ A 'brute force' solution to a beautiful problem. I don't claim this answer is as insightful as the others and the question is somewhat old, but I feel it is relevant and unique enough to merit posting. As usual, we will let $\S(x) = \sin(x)/x$ with $\S(0)=1$. The big idea: use angle-addition, Taylor series, and ...

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Top 50 recent answers are included


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# Using a DE-SW050 5volt regulator and a USB breakout board to charge an iPod in a car

I need a clean install of an iPod charger in my car. That means not a wire running from a 12 volt socket. I've looked at the Belkin flush chargers and they are beautiful, but require a socket.

I'm considering wiring one to a panel mount USB adaptor using a DE-SW050 voltage regulator. It'll take up to 30 volts (so 12 is trivial) and outputs 5 volts at 1amp max (iPad compatible). The wiring seems trivial: An in, and out, and a common ground. With a breakout board and the Cables to Go panel mount, (and a fuse in line with the 12 volts) this seems like a trivial solution.

Is it viable and device-safe? It seems like such a clean design that there must be a catch.

The other question I had was if it was possible to then add an LED to indicate that the 5 volts was being used. (Putting it in-line perhaps? But what about voltage drop?)

Help would be much appreciated.

• That looks a costly device - surely something like an LM317T and a couple of resistors and capacitors would do the same job at a fraction of the price? – Majenko May 28 '11 at 22:18

## 2 Answers

The automotive environment is electrically very noisy, with potentially large spikes on the 12 V power bus (especially during engine start). This can be mitigated through the use of large filtering capacitors, maybe an inductor inline on the supply, and perhaps a transorb or other protection device. I don't know enough about power supply filtering to tell you exactly what to do, but you might be able to Google "automotive power supply filter" or similar. Note that the regulator may require input and output bypass capacitors, too.

Then there's the issue of iPad fast charging. I'm not sure how it decides it can draw more current for charging than what is normally allowed by the USB spec. I think there are resistors of a specific value between certain pins on the supply side. If you don't care about fast charging (which I've heard the iPhone 4 also uses), then you can ignore this.

You don't want to put an LED inline in order to see that power is being drawn. An LED has a maximum forward current above which its lifespan is dramatically shortened. This forward voltage is typically 5 - 25 mA, far less than the 1000 mA your regulator is capable of delivering (and far less than the 500 mA the iPod will likely draw). An alternative would be to set up a high-side current sense resistor (inline on the +5V side) and high-side current sense amplifier, use the output of that to drive a MOSFET or other transistor to turn on an LED. There are probably other ways to do that, but that's what comes to mind.

It really is easier to buy an off-the-shelf USB charger with a suitable input voltage, and cut off the supply connector to wire it in (with a fuse!) to your car supply. As another commenter mentions later, it may still lack appropriate filtering. You should be able to buy an automotive power filter to put inline with the USB charger. Then plug the Cables to Go panel mount into the charger.

• Ugh, that seems like way over my head. The device takes up to 30volts. Do the spikes likely get that high? The spec sheet seems pretty much in/out voltages. 1amp is the max that MacBookPro USB puts out. But this seems to indicate that this isn't going to be as simple as it would seam. Thanks sir! – Scott Anguish May 28 '11 at 6:52
• Well, it's not that the spikes would damage the regulator, it's that it wouldn't react fast enough to clamp them on the output. They might "get through" to the connected device. Moreover, the power is noisy, which might introduce noise on the analog outputs or erratic behavior in the device. Erm...see my updated answer. – Rick M. May 28 '11 at 7:10
• @Scott Automotive regulators for 12V vehicles have to be rated to handle up to 60V for t < 100ms and 28V continuously (i.e. double battery jump start.) Often, negative spikes are tolerated too. And yes, 60V spikes are not uncommon in even small vehicles. They are called load dumps and they can occur when you switch lights on or off, but also any number of other power hungry systems can cause spikes due to the high inductance of the alternator. – Thomas O May 28 '11 at 10:20

You're going to need voltage divider on the USB data lines as explained in this answer. This controls the charging modes for iDevics and is needed for them to start charging.

Next, the datasheet says that there are already integrated capacitors in the regulator, but I'd still recommend that you add some extra ones at the output.

Another thing worth pointing out is the derating figure in the datasheet. Temperatures inside of the vehicle can get high, especially if you're going to place the regulator in an area with low ventilation. If you want to run it at 1 A, do take into account the graph. To me it seems that the maximum safe outside temperature would be around 35 degrees. You need to be sure that you have lower temperature when you're using the charger. Another problem is the unusual package. To me it looks like there's no easy way to add a heatsink to the device.

• Thanks. It seems more and more attractive to just solder directly to a third party completed unit and tap into the wires on the 12 volt socket to power it. :-( Now I wish I hadn't just ordered the damn thing. – Scott Anguish May 28 '11 at 6:56
• @Scott Anguish Well, it it will make you feel better, most of the cheaper car chargers I've seen don't have much (or even any) protections Rick M. recommended. Still, if you can, do add them. Most of the iDevices are very expensive and you don't want to risk them on a cheap car charger. Capacitors should be cheap and easy to obtain, but make sure you use ones rated at 35 V or higher, just to be safe. The datasheet for regulator recommends 470 $\mu F$ on sensitive output. – AndrejaKo May 28 '11 at 7:03