A. The metabolism of an organism comprises all the chemical reactions that occur, including those involved in obtaining energy, producing new cells, maintaining homeostasis,
communicating, and reproducing.
B. The energy that organisms need to live and grow is found in the chemical bonds in the
food they use
C. In addition to energy, food supplies living things with building
block elements.
D. Homeostasis is the tendency of all living things to maintain balance and control of the
chemical reactions occurring within them.
E. Communication between living things can be either physical or chemical.
F. Reproduction involves duplicating parts of the cell through chemical reactions.

1.__ All living things use food, grow, and reproduce.
2. __Carbon, oxygen, and hydrogen are all found in sugar.
3.__ Humans perspire when they are warm and shiver when they are cold.
4. __Dogs smell trees and other things in the environment to learn about other
animals in the area
5. __Foods high in carbohydrates are often eaten by athletes before big
sporting events.
6.__ Your hair and fingernails grow quickly throughout the year.
7.__ Humans get thirsty when the temperature is very warm.
8. __The characteristics of DNA enable organisms to reproduce.
9.__ Birds often make loud noises when cats are nearby.