Unit 3 Review Flash Cards - Molecular Cell Biology

Front

What is the most likely outcome if a small hole is introduced into a lipid bilayer?

Back

The membrane reseals itself.

Front

What is the primary type of lipid found in the cell membrane?

Back

phospholipids

Front

Which membrane lipid maintains fluidity and lacks a glycerol backbone? Options: phosphatidylcholine, a glycolipid, phosphatidylserine, cholesterol.

Back

cholesterol

Front

What role does the bilayer arrangement of phospholipids play in increasing the entropy of the system, thereby making membrane formation energetically favorable?

Back

Water molecules form structured cages around hydrophobic molecules, promoting their aggregation and reducing water contact.

Front

Which of the following statements is true regarding the behavior of lipids in cell membranes?

• The hydrocarbon tails of membrane lipids act like stiff rods.
• Individual lipids tumble end over end within a single monolayer.
• Membrane lipids diffuse laterally within the plane of the membrane.
• Membrane lipids frequently flip-flop between one monolayer and the other.

Back

Membrane lipids diffuse laterally within the plane of the membrane.

Front

A bacterium is transferred from a warm human intestine to a colder environment. What change might it implement to preserve the fluidity of its cell (plasma) membrane?

Back

introduce lipids with shorter hydrocarbon tails and more double bonds

Front

What final products do you expect to accumulate through the action of the enzyme monoacylglycerol lipase?

Back

glycerol and free fatty acid

Front

What factor is responsible for establishing compositional asymmetry in the plasma membrane between the extracellular and cytosolic layers?

Back

flippase

Front

Where does most new membrane synthesis take place in a eukaryotic cell?

Back

in the endoplasmic reticulum

Front

What happens if a cell membrane undergoes a large tear?

Back

movement between lipid layers