What acts as a "check" valve to prevent blood from flowing back into the ventricle?

the answer is "a.) well–developed vascular system."

explanation:

lipid

explanation:

some fungi obtain their nutrients from a living host (plant or animal) and are called most biotrophic fungi have fairly narrow host ranges—they are specialized on a limited called rhizomorphs that allow the fungus to grow from one tree to another. ascospores are formed inside a sac-like structure called an ascus. so your answer is a

. the sierra madre fault zone of southern california

. the san andreas fault california