what advantages do animal pollination bring to angiosperms that might explain the dominance of these relative newcomers among the plants?

the endomembrane system i think

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.  

answer(1) tab per dose.;