Some what will kill their host, while others won't?
Options:
- (A) barnacles
- (B) producers
- (C) scavengers
- (D) insects
- (E) cigarettes
- (F) fungi
- (G) plants
- (H) leeches
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Let's think first: Some parasites kill their host, but most do not. Leeches are external parasites. Some leeches will kill their host, but most do not.... So the answer is [(H)]


What is bilaterally symmetrical and a protostome?
Options:
- (A) gastropod shells
- (B) honeybees
- (C) humans
- (D) shells
- (E) bears
- (F) the common snail
- (G) peachleaf willow
- (H) the eyes
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Let's think first: Mollusks are invertebrates such as the common snail. Mollusks are bilateraly symetrical and are protostomes. The common snail is bilaterally symmetrical and a protostome.... So the answer is [(F)]


Muscle and internal organs are protected by:
Options:
- (A) immunization
- (B) fur
- (C) fat
- (D) bone
- (E) hair
- (F) skin
- (G) defense
- (H) copper
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Let's think first: Bone provides protection for soft tissues and internal organs. Soft tissue refers to the soft connective or supporting tissues, such as muscle. Bone provides protection for muscles and internal organs.... So the answer is [(D)]


Brain tumors occur when what is no longer regulated?
Options:
- (A) fossil fuels
- (B) headaches
- (C) voltage
- (D) heat or cold
- (E) cell cycles
- (F) critical organs
- (G) cerebellum
- (H) migraines
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Let's think first: Cancer is a disease that occurs when the cell cycle is no longer regulated. Brain tumors are one of the fastest growing cancers today. Brain tumors occur when the cell cycle is no longer regulated.... So the answer is [(E)]


Specialization occurs when competing groups of interbreeding individuals evolve different what?
Options:
- (A) color of leaves
- (B) fur and fat
- (C) forces
- (D) colors
- (E) frontal zones
- (F) graptolites
- (G) sensory neurons
- (H) adaptations
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Let's think first: Specialization occurs when competing species evolve different adaptations. Species is a group of interbreeding individuals. Specialization occurs when competing groups of interbreeding individuals evolve different adaptations.... So the answer is [(H)]


Many corals secrete what to form a coral reef?
Options:
- (A) Chlorophyll
- (B) salt and water.
- (C) The area was once underwater
- (D) Chemical energy
- (E) aqueous solution
- (F) Organic compounds
- (G) gastropod shells
- (H) hard outer covering
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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: Many corals secrete an exoskeleton that builds up to become a coral reef. An insect has a hard outer covering called an exoskeleton. Many corals secrete a hard outer covering that builds up to become a coral reef.... So the answer is [(H)]