What is a single phospholipid molecule composed of?
Hydrophilic, polar phosphate head and a hydrophobic, non-polar hydrocarbon tail.
How do the hydrophobic and hydrophilic properties of the phospholipid bilayer allow a membrane to maintain its structure?
When phospholipids are mixed with water, the phosphate heads are attracted to the water while the hydrocarbon tails are attracted to each other, but not water. This causes the phospholipids to form a bilayer with tails facing each other and heads facing the water on the outside and inside of the cell.
Function of channel/carrier proteins?
passive transport across the membrane
function of protein pumps?
active transport across membrane
function of receptor proteins?
hormone binding and recognition
function of enzymes?
used in cell surface reactions
function of adhesion proteins?
binding cell together
function of neurotransmitter receptors?
communication between cells
Differentiate between integral and peripheral proteins.
-Integral proteins are at least partly hydrophobic on their surface and are found embedded in the hydrocarbon chains of the phospholipids. -Peripheral proteins are usually hydrophilic on their surface and are not embedded throughout the membrane.
What is the function of glycoproteins in the plasma membrane? Cholesterol?
-Glycoproteins give structural support to cells -Cholesterol forms the outer coating of cells
Label the fluid mosaic model.
c. receptor protein
d. phospholipid tails
e. phospholipid bilayer
f. phospholipid heads
g. peripheral membrane protein
i. integral membrane protein/protein channel
What is the chemical components of a phospholipid?
Phosphate tip of the head attached to glycerol group. Glycerol group ties into hydrocarbon tails. Tails bent at double bonds between carbons.