25 points
which of the following represents one of the steps through which simple cells are hypothesized to have been produced?

a abiotic synthesis of small organic molecules

b formation of nitrogenous bases from amino acids

c joining of self-replicating molecules into protocells

d packaging of inorganic macromolecules into vesicles

C. Joining of self-replication molecules into protocells.

Explanation:

For the origin of life, at least three conditions are needed.  

The radiation received from the sun on the early earth must have fulfilled the requirement of mutation. The mutation is necessary for bringing variation in the genetic material thus driving evolution. To protect the self-replicating molecules from the external environment and to keep them together, the molecules must have been enclosed in a membrane barrier, which should be selectively semipermeable, to facilitate the exchange of molecules.

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.