d. vacuole
17. The fluid mosaic model presents the modern view of
a. a membrane ' s structure
b. chromosomes
c. aggregates of cells
d. the nucleus
18. Which is not a principle of the cell theory?
a. All matter consists of at least one cell.
b. Cells are the basic units of life.
c. All cells arise from preexisting cells.
d. All organisms are made of one or more cells.
19. A cell membrane is a thin layer of lipid and
a. monosaccharides
b. protein
c. chitin
d. water
20. Immerse a living cell in a isotonic solution, and water will tend to
a. diffuse into the cell.