is not required for anaerobic respiration.

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.

There are only about 250,000 known fossil species. true or false

Because water is a polar molecule it makes an excellent solvent for atoms and compounds found within cell and tissue. water acting as a solvent in organisms, aids in all of the following except