Compare diagram b to diagram a. how is it different?

Sea stars, sea urchins, sand dollars, and brittle stars are all memeber of a group, what is the common name of the group they are all in

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.

When is your breathing likely to speed up? a. when your white blood cells increase b. when your cells need more energy c. when your heart cells need more carbon dioxide d. when your blood cells have too much oxygen