The lack of allele variation in the northern elephant seal population is an example ofa) niche differentiation.

well, you see. the answer to your question is quite simple. the thing that is big, powerful, and over 9,000 is your mom.

i think that it is c, d, and e, hope this

these muscles maintain the blood pressure in the vessels. the smooth muscles are innervated by nerves of the autonomic nervous system. when the muscles contract, they cause vasoconstriction of the vessels and increase blood pressure. when the muscles relax, they enable vasodilation of the   blood vessels hence reduce blood pressure.