What is not made up of cells?
Options:
- (A) an object
- (B) Veins and arteries.
- (C) Tobacco mosaic
- (D) an organism's body
- (E) Conifers
- (F) sensory neurons
- (G) layers of fat
- (H) the digestive system
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Let's think first: Viruses are not cells. Viruses include the Tobacco Mosaic Virus. Tobacco mosaic is not made up of cells.... So the answer is [(C)]
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Some insets can use their antennae to detect what?
Options:
- (A) light waves
- (B) photons
- (C) Electrical energy
- (D) vibrating air
- (E) new lands
- (F) water sources
- (G) bending light rays
- (H) electricity
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Let's think first: Some insects can use their antennae to detect sound. When ears detect the vibrating air, signals are sent to the brain that are interpreted as sounds. Some insets can use their antennae to detect vibrating air.... So the answer is [(D)]
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What do organisms cluster around, in the ocean floor?
Options:
- (A) cracks
- (B) chemicals
- (C) limestone
- (D) crust
- (E) headaches
- (F) Nutrients
- (G) horses
- (H) dogs
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Let's think first: Organisms cluster around hydrothermal vents in the ocean floor. Background Hot water vents form inside cracks in the ocean floor. Organisms cluster around cracks in the ocean floor.... So the answer is [(A)]
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What unwanted creature would be found on the surface of a human body using it as a host? 
Options:
- (A) Tapeworm.
- (B) Leeches.
- (C) Pesticides
- (D) animals
- (E) insects
- (F) Hookworm
- (G) bacteria
- (H) Bracelet.
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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: Some parasites live on the surface of their host. Leeches are external parasites. Leeches are on the surface of the host .... So the answer is [(B)]
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