Conditions in the environment that impact the size of the population are called

What is the significance of the protein-lined pits? a. protein attracts other proteins needed for atp synthesis within the cell. b. protein-lined pits are able to transport one molecule at a time down the concentration gradient within the cell. c. the polarity of proteins allows other polar molecules to attach and be transported in the cell by transport channels. d. receptors within the pits allow ligands to fuse and be transported into the cell by endocytosis.

Need with these questions . need the answers in a rush for these questions are the answers i put down are correct or not? ?

Stem cells found adult tissue such as in bone marrow brain muscle skin and liver are only capable of what