Ques:Q: What term describes a drug that has an effect on the central nervous system? Read this paragraph and choose the correct option from the provided answers: Caffeine is an example of a psychoactive drug. It is found in coffee and many other products (see Table below ). Caffeine is a central nervous system stimulant . Like other stimulant drugs, it makes you feel more awake and alert. Other psychoactive drugs include alcohol, nicotine, and marijuana. Each has a different effect on the central nervous system. Alcohol, for example, is a depressant . It has the opposite effects of a stimulant like caffeine. Choices: - nonaddictive drug - elemental drug - steroidal drug - psychoactive drug A:

Ans:psychoactive drug
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Ques:Q: What distinguishing characteristic of annelid anatomy shows specialization and adaptation? Read this paragraph and choose the correct option from the provided answers: Annelids are divided into many repeating segments. The earthworm in Figure below is an annelid. You can clearly see its many segments. Segmentation of annelids is highly adaptive. Each segment has its own nerve and muscle tissues. This allows the animal to move very efficiently. Some segments can also be specialized to carry out particular functions. They may have special structures on them. For example, they might have tentacles for sensing or feeding, "paddles" for swimming, or suckers for clinging to surfaces. Choices: - asymmetry - beautiful - compression - segmentation A:

Ans:segmentation
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Ques:Q: Large increases in the diversity of life have resulted from adaptive radiations that followed what? Read this paragraph and choose the correct option from the provided answers: Choices: - mass mutations - mass migrations - glaciers - mass extinctions A:

Ans:mass extinctions
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Ques:Q: Overpopulation takes place when the number of organisms in an area exceeds what? Read this paragraph and choose the correct option from the provided answers: Overpopulation takes place when the number of organisms exceeds the carrying capacity of the region. What is the carrying capacity of Earth for humans? Are seven billion people the human carrying capacity? Nine billion? We don't know yet. Choices: - consumers - predators - biome size - carrying capacity A:

Ans:
carrying capacity
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