Biological Membrane

Question 1

What is the term applied to a molecule such as a phospholipid that has distinct regions that are “water-loving” and “water-hating?”

Answer 1

Amphiphilic

Question 2

In terms of membrane fluidity, a lipid bilayer sheet can be considered a two-dimensional fluid, whereas a spherical liposome cannot.
True or False

Answer 2

False

Question 3

Imagine two lipid bilayers. In one, all the hydrocarbon chains are saturated (no double bonds).
In the other, all the hydrocarbon chains are unsaturated (with cis-double bonds).
What predictions about their fluidity and permeability to water-soluble molecules can be made?

Answer 3

The bilayer with saturated Chains would be less fluid and less permeable

Question 4

What is the term applied to a molecule such as a phospholipid that has distinct regions that are “water-loving” and “water-hating?”

Answer 4

Amphiphilic

Question 5

In terms of membrane fluidity, a lipid bilayer sheet can be considered a two-dimensional fluid, whereas a spherical liposome cannot.
True or False

Answer 5

False

Question 6

Imagine two lipid bilayers. In one, all the hydrocarbon chains are saturated (no double bonds).
In the other, all the hydrocarbon chains are unsaturated (with cis-double bonds).
What predictions about their fluidity and permeability to water-soluble molecules can be made?

Answer 6

The bilayer with saturated chains would be less fluid and less permeable

Question 7

Only transmembrane proteins can function on both sides of the bilayer or transport molecules across it.
True or False

Answer 7

True

Question 8

What is the term for the outer coat of a eukaryotic cell, composed of oligosaccharides linked to intrinsic plasma membrane glycoproteins and glycolipids, as well as proteins that have been secreted and reabsorbed onto the cell surface?

Answer 8

Carbohydrate Layer

Question 9

What is a complex network of proteins and polysaccharide chains that the cells secrete. It is not composed of transmembrane proteins, although such proteins can maintain attachments to the matrix.

Answer 9

Extracellular Matrix

Question 10

What is a specialized layer of cytoplasm on the inner face of the plasma membrane. It is an actin-rich layer responsible for movements of the cell surface.

Answer 10

Cell Cortex