Biology Review

4. The study of the relationships between organisms and their environment.
7. The movement of molecules from a region of lower concentration to a region of higher concentration with the use of energy.
10. A process in which the outputs of a system are circled back and used as inputs.
11. The basic building blocks of carbohydrates.
13. Basic Unit of Life
14. ________ Feedback occurs in nature when the product of a reaction leads to an increase in that reaction.
15. The basic building blocks of proteins.
17. The control center of a cell that contains genetic material.
18. The process by which cells divide to produce new cells.
19. ________ Feedback is a normal biological response in which the effects of a reaction slow or stop that reaction.
20. RESPIRATION The process of breaking down food to release energy.

1. The process by which plants release oxygen and take in carbon dioxide.
2. The process by which organisms obtain energy from food.
3. SYSTEM The body's first line of defense against pathogens.
5. The structures in a cell that carry out specific functions.
6. The process of maintaining stable internal conditions in the body.
8. The protective outer covering of a cell.
9. A type of membrane transport that does not require energy to move substances across cell membranes.
12. The study of heredity and variation in living organisms.
16. A green pigment found in plants that is responsible for photosynthesis.