Q: In their pure form, all elements have an oxidation number of what? Choices: - 3 - 2 - 7 - zero A:
zero

Q: A penguin must do what before molting? Choices: - hibernate - use muscle mass - mate - increase muscle mass A:
increase muscle mass

Q: Q: Which part of the body of amphibians, easily absorbs substances from the environment? Choices: - liver - scales - Eyes - skin A:
A: skin

Question: Q: Chemical changes occur because of what? Choices: - liquid reactions - evaporation - toxic reactions - chemical reactions A:
Answer: chemical reactions

*Question*
Q: Osteoclasts break down bone to maintain mineral what? Choices: - density - fluctuations - polarity - homeostatis A:
**Answer**
homeostatis

(Question)
Q: A sperm cell and an egg cell fuse to become what? Choices: - embryo - fetus - unfertilized egg - fertilized egg A:
(Answer)
fertilized egg