Plasma Membrane

Which type of biological macromolecule is the main component of the plasma membrane?

• carbohydrate

• phospholipid

• protein

• cholesterol

What is the function of cholesterol in a plasma membrane?

• To make the membrane flexible

• To control the effect of temperature changes on membrane fluidity

• To attract water molecules

• To allow nutrients and other essential molecules into the cell

What is the "big idea" of the Fluid Mosaic Model of plasma membranes?

• the plasma membrane creates a specialized FLUID that looks like a MOSAIC.

• the plasma membrane is a MOSAIC.

• the fluid mosaic model is NOT related to the plasma membrane.

• a plasma membrane is a MOSAIC of components that move FREELY and FLUIDLY.

Which is NOT a function of the membrane?

• it forms a selective barrier

• it has receptors for chemical messages

• it is the control center of the cell

• it is involved in self recognition

Which of the following substances would have the most trouble crossing the membrane by diffusing through the bilayer?

• water

• oxygen

• carbon dioxide

• a sodium ion

A major function of glycoproteins and glycolipids in the membane is to

• glue cells together to form tissues

• allow cells to identify each other

• attach membrane to cytoskeleton

• help retain shape

When doctors perform organ transplants, they choose a donor tissue match. Which component is being matched?

• membrane phospholipids

• peripheral proteins

• cell surface carbohydrates

• cholesterol

What kinds of molecules pass through a cell membrane most easily?

• small and hydrophilic

• small and hydrophobic

• large and polar

• large and hydrophobic

How does cholesterol affect the cell membrane at low temperatures?

• helps it from becoming too rigid

• makes it more viscous

• denatures it

• assures it solidifies

What property does the phospholipid bilayer give to a plasma membrane?

• provides the barrier between the inside and outside of the cell

• communicates between cells

• conducts electrical impulses in nerve cells

• allows cells to bind to each other