Chapter 8

2. fluid portion of the cell outside the nucleus
4. reticulum, internal membrane system found in eukaryotic cells
6. relatively constant internal physical and chemical conditions that organisms maintain
7. converts the chemical energy stored in food into compounds that are more convenient for the cell to use
9. cell organelle that breaks down lipids, carbohydrates, and proteins into small molecules
11. membrane, thin, flexible barrier that surrounds all cells, regulates what enters and leaves the cell.
12. unicellular organism that lacks a nucleus
14. organism whose cells contain a nucleus
19. captures the energy from sunlight and converts it into chemical energy
20. , group of similar cells that perform a particular function
24. when the concentration of two solutions is the same
26. diffusion, process of diffusion in which molecules pass across the membrane through cell membrane channels
27. basic unit of all forms of life
28. water channel protein in a cell
29. bilayer, flexible double-layered sheet that makes up the cell membrane and forms a barrier between the cell and its surroundings
30. when comparing two solutions, the solution with the lesser concentrations of solution
31. the structure that contains the cell's genetic material in the form of DNA

1. cell organelle that stores materials such as water, salts, proteins, and carbohydrates
2. gives the cell its shape and internal organization and is involved in movement.
3. system, group of organs that work together to perform a specific function
5. pressure, pressure that must be applied to prevent osmotic movement across a selectively permeable membrane
8. specific protein to whose shape fits that of a specific molecular messenger
10. cell organelle consisting of RNA and proteins found throughout the cytoplasm in a cell
13. wall, strong, supporting layer around the cell membrane in some cells
15. group of tissues that work together to perform closely related functions
16. apparatus, organelle in cells that modifies, sorts, and packages proteins and other materials for storage
17. diffusion of water through a selectively permeable membrane
18. theory, fundamental concept of biology that states that all living things are composed of cells.
21. specialized structure that performs cellular functions within a eukaryotic cell
22. when the comparing two solutions, the solution with the greater concentration of solution
23. process by which particles tend to move from an area where they are more concentrated to an area where they are less concentrated
25. permeable, property of biological membranes that allows some substances to pass across it while others cannot