What wets the skin, and when it evaporates, it cools the body?
Options:
- (A) heat energy
- (B) acetic acid
- (C) Air conditioner
- (D) salt and water.
- (E) Skin oil
- (F) water vapor
- (G) Perspiration
- (H) A towel
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Let's think first: Sweat wets the skin, and when it evaporates, it cools the body. Perspiration There are about 2 million sweat glands in the average human body. Perspiration wets the skin, and when it evaporates, it cools the body.... So the answer is [(G)]


Roundworms can be free-living or live on a what?
Options:
- (A) soil
- (B) nest
- (C) host
- (D) root
- (E) stem
- (F) habitat
- (G) food
- (H) commune
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Let's think first: Roundworms may be free-living or parasitic. Parasites Shortfin makos host a variety of parasitic copepods. Roundworms may be living on a host or free-living.... So the answer is [(C)]


What increases the productivity and stability of ecosystems?
Options:
- (A) Fully cooking the oysters
- (B) genetic uniformity
- (C) genetic diversity
- (D) extinction
- (E) agriculture
- (F) disease
- (G) Earth orbiting the Sun
- (H) recycling
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Let's think first: Biodiversity increases the productivity and stability of ecosystems. Biodiversity is basically genetic diversity. Genetic diversity increases the productivity and stability of ecosystems.... So the answer is [(C)]


The bonds of that which when heavy is deuterium cause what to expand when it freezes?
Options:
- (A) matter
- (B) rings
- (C) CO 2
- (D) liquids
- (E) gas
- (F) solutes
- (G) cations
- (H) water
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Let's think first: Hydrogen bonds cause water to expand when it freezes. Deuterium, or heavy hydrogen, is an isotope of hydrogen, or a hydrogen atom with a neutron added. The bonds of that which when heavy is Deuterium cause water to expand when it freezes.... So the answer is [(H)]


Neurotransmitters and hormones are what in their function?
Options:
- (A) cells
- (B) organic
- (C) inorganic
- (D) complex
- (E) Vibrates
- (F) warm
- (G) properties
- (H) similar
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Let's think first: Hormones are chemical messengers that control many body functions. Neurotransmitters are chemical messengers in the brain. Hormones and neurotransmitters behave in common ways.... So the answer is [(H)]


What kind of animals conserve energy with their hair or fur?
Options:
- (A) fur
- (B) bears
- (C) mammals
- (D) sweating
- (E) frogs
- (F) cactus
- (G) goats
- (H) humans
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Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Let's think first: Mammals conserve body heat with their hair or fur. Basically, heat is energy. Mammals conserve energy with their hair or fur.... So the answer is [(C)]