The "voices" of a cell, which carry messages, are
A. surface receptors.
B. platelets.
C. cytokines.
D. antigens.
C
You might also like to view...
Cells undergo exocytosis ____
a. to pump protons down a concentration gradient b. when replicating c. to secrete protein and wastes from the cell d. to ingest nutrients e. as a means of cellular protection
The respiratory membrane consists of alveolar epithelium, capillary endothelium, and ____
a. a lubricating secretion b. a connective tissue layer c. a fused basement membrane d. gas e. a pleural membrane
Microbes that reduce N2 to NH3 engage in nitrogen _____.
Fill in the blank(s) with the appropriate word(s).
Hydrophilic molecules
A) do not readily dissolve in water. B) are repelled by water. C) are neutral and nonpolar. D) form hydrogen bonds among themselves. E) readily dissolve in water.