Cells

1. a thin, flexible barrier that surrounds a cell and controls which substances pass into and out of a cell
5. single celled
7. a tiny cell structure that carries out a specific function within the cell
8. sac-like organelle that stores water, food, or other materials
9. the maintenance of stable internal conditions
11. an organelle in the cells of plants that capture energy from sunlight and changes it to an energy form that cells can use in making food
12. any living thing
15. all cells share the same ...
19. a widely accepted explanation of the relationship between cells and living things

2. organism consisting of many cells
3. any change in an environment that can make an organism react in some way
4. a large oval organelle that contains the cell's genetic material in the form of DNA and controls many of the cell's activities
6. last name of the man who built his own microscope to learn about nature
10. convert energy stored in food to energy the cell can use to live and function
13. basic unit of function and structure in living things
14. this invention made the discovery of cells possible
16. an action or change in behavior
17. fills the region between the cell membrane and the nucleus
18. the rigid supporting layer that surrounds the cells of plants