7. The impermeability of the cell membrane to water-soluble molecules is a result of the: Select one : O A. nonpolar nature of water molecules. O B. presence of proteins that extend through both layers of the membrane. O C. presence of cellulose and other polysaccharides in the membranes. O D. presence of phospholipids in the membrane.

D. presence of phospholipids in the membrane.

lizards have adapted to life in the desert. some desert lizards have toes with spiny scales to them run across the sand without sinking. some use the sand to hide from predators, or to search for small animals that they prey upon.

the diploid number of chromosomes is sometimes represented by the symbol 2n. for the fruit fly, the diploid number is 8, which can be written as 2n = 8, where n represents twice the number of chromosomes in a sperm or egg cell.