Question: Q: Which stage of development is a period during which apoptosis is widespread and plays a crucial role? Choices: - puberty - transgenic - infancy - embryonic A:
Answer: embryonic

Question: Q: What causes rivers to always flow downhill? Choices: - slope - pressure - diffusion - gravity A:
Answer: gravity

Question: Q: The layers of the atmosphere correspond with what changes with altitude? Choices: - friction - nitrogen - oxygen - temperature A:
Answer:
temperature