Logic for the Q&A below: All chemical reactions require activation energy to get started. Chemical changes are a result of chemical reactions. Activation energy must be used before a chemical change happens.
Q: What is required before a chemical change?
Options:
- (A) kinetic energy
- (B) energy usage
- (C) activation push
- (D) activation energy
- (E) activation switch
- (F) activation power
- (G) Burning fuel and air
- (H) Evaporation
A: (D)
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Logic for the Q&A below: Echinoderms lack a centralized nervous system. From animal experiments, it seems to be a central nervous system toxin. Echinoderms are resistant to some toxins.
Q: Echinoderms are resistant to some:
Options:
- (A) starfish
- (B) enzymes
- (C) Toxicity
- (D) pesticide
- (E) parasites
- (F) toxins
- (G) boats
- (H) chemicals
A: (F)
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Logic for the Q&A below: Echinoderms have a unique water vascular system with tube feet. Another group of echinoderms are the echinoids. Echinoids have unique water vascular system was tube feet.
Q: Which has a unique water vascular system?
Options:
- (A) roots
- (B) trees
- (C) Conifers
- (D) Echinoids
- (E) fur seals
- (F) Most plants
- (G) ferns
- (H) bushes
A: (D)
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Logic for the Q&A below: 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.

Q: 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
A: (H)
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