A) mitochondria.
B) a cell membrane.
C) a cell wall.
D) a nucleus.
E) microtubules.

A) they have hydrophobic heads and hydrophilic tails.
B) they have polar heads and nonpolar tails.
C) they have polar tails and nonpolar heads.
D) the phospho-portion can form phosphodiester bonds between adjacent phospholipids.
E) two of these.

A) covalent bonding between membrane lipids.
B) hydrogen-bonding between the phospholipids' tails.
C) repulsion between the phospholipids' tails and water.
D) covalent bonding between the ends of phospholipids tails in opposite layers.
E) hydrogen-bonding between the head groups of the phospholipids.