There can be different variations of a trait known as

the offspring of crosses between parents with different traits?. Such as, the process by which peas are allowed to self-pollinate and produce offspring identical to themselves. A specific characteristic that varies from one individual organism to another. The offspring of crosses between parents with different traits. The chemical factors that are passed from one generation to the next.

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.