Cell membranes
a. consist almost entirely of protein molecules
b. are impermeable to fat-soluble substances
c. in some tissues permit the transport of glucose at a greater rate in the presence of insulin
d. are freely permeable to electrolytes but not to proteins
e. have a stable composition throughout the life of the cell
a. consist almost entirely of protein molecules
b. are impermeable to fat-soluble substances
c. in some tissues permit the transport of glucose at a greater rate in the presence of insulin
d. are freely permeable to electrolytes but not to proteins
e. have a stable composition throughout the life of the cell