2. Cell Chemistry & Cell Components

The fluid mosaic model of the membrane proposed that membranes:

Which of the following best describes the arrangement of the main component of the plasma membrane?

a. A monolayer of phospholipids with the phosphate heads facing the cytosol and the fatty acid tails facing the extracellular fluid

b. A bilayer of phospholipids with the phosphate heads facing the cytosol and extracellular fluid, and the fatty acid tails facing one another

c. A bilayer of phospholipids with the phosphate heads of one layer facing the fatty acid tails of the other

d. A bilayer of phospholipids with a layer of triglycerides sandwiched in the middle

Mark the following statements about the plasma membrane as true or false. If a statement is false, correct it to make a true statement.

a. Integral membrane proteins generally span the width of the plasma membrane, whereas peripheral proteins are found on only one side of the membrane.

Mark the following statements about the plasma membrane as true or false. If a statement is false, correct it to make a true statement.

b. Cholesterol provides the plasma membrane with stability in the face of changing ion concentrations.

Mark the following statements about the plasma membrane as true or false. If a statement is false, correct it to make a true statement.

c. Membrane cholesterol is vital for cell-cell recognition.

Mark the following statements about the plasma membrane as true or false. If a statement is false, correct it to make a true statement.

e. The overall structure of the plasma membrane is a mosaic with the components locked tightly in place.

Explain how the members of the endomembrane system interact.