Q: Isotopes have different number of these in their nuclei? Choices: - protons - electrons - atoms - neutrons A:
neutrons

Q: What precious resource allows us to grow food as well as materials we turn into clothing and medicine? Choices: - petroleum - mercury - gasoline - soil A:
soil

Q: Q: Gall bladder removal surgery does not seriously affect digestion because ______ is still being produced. Choices: - saliva - blood - plasma - bile A:
A: bile

Question: Q: What is the clear, curved structure that works with the cornea to help focus light at the back of the eye? Choices: - pupil - retina - iris - lens A:
Answer: lens

*Question*
Q: Energy that the sun and other stars release into space is called what? Choices: - static energy - kinetic energy - mechanical energy - electromagnetic energy A:
**Answer**
electromagnetic energy

*Question*
Q: What branch of biology focuses on heredity? Choices: - botany - cell biology - zoology - genetics A:
**Answer**
genetics