Single-celled organisms are able to maintain internal stability because they : a - contain structures that perform life functions b - work with other cells c - carry out photosynthesis to produce food d - have multiple organisms

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.