Q: An important chemical compound, which supplies living things with the energy they need to survive, is composed of carbon, oxygen and atoms of what other element? Choices: - magnesium - nitrogen - calcium - hydrogen A:
hydrogen

Q: What do willow trees produce to kill bacteria? Choices: - chlorophyll - enzymes - cytoplasmic acid - salicylic acid A:
salicylic acid

Q: Q: What is one function of the nervous system in humans? Choices: - controlling emotion - producing hormones - controlling thought - controlling muscles A:
A: controlling muscles

Question: Q: Electrons in inner shells are called what? Choices: - inner electrons - surface electrons - valence electrons - core electrons A:
Answer: core electrons

*Question*
Q: Researchers have also used insect courtship to explore genetic variation underlying differences in what? Choices: - reproduction - function - instance - behavior A:
**Answer**
behavior

*Question*
Q: What two organs secrete fluids that aid in digestion? Choices: - kidney and gall bladder - stomach and lung - spleen and bladder - pancreas and liver A:
**Answer**
pancreas and liver