Which of the following is an example of an adaptation?
a. birds that live near a highway learn not to fly away every time a car passes.
b. the coloring of a monarch butterfly alerts predators to the fact that the butterfly is poisonous.
c. a dog sits when it hears a command because the owner rewards it with food.
d. pigeons make their nests near an outdoor restaurant, where food is always available.

What is the significance of the protein-lined pits? a. protein attracts other proteins needed for atp synthesis within the cell. b. protein-lined pits are able to transport one molecule at a time down the concentration gradient within the cell. c. the polarity of proteins allows other polar molecules to attach and be transported in the cell by transport channels. d. receptors within the pits allow ligands to fuse and be transported into the cell by endocytosis.