Chapter 7 Biology

Who was/were the first to propose that cell membranes are phospholipid bilayers?

Some regions of the plasma membrane, called lipid rafts, have a higher concentration of cholesterol molecules. As a result, these lipid rafts

Singer and Nicolson's fluid mosaic model of the membrane proposed that

What are the major structural components of the cell membrane?

The presence of cholesterol in the plasma membranes of some animals

According to the fluid mosaic model of cell membranes, which of the following is a true statement about membrane phospholipids?

Which of the following is one of the ways that the membranes of winter wheat are able to remain fluid when it is extremely cold?

In order for a protein to be an integral membrane protein it would have to be

Which of the following is a reasonable explanation for why unsaturated fatty acids help keep any membrane more fluid at lower temperatures?

Which of the following is true of integral membrane proteins?

The primary function of polysaccharides attached to the glycoproteins and glycolipids of animal cell membranes is

An animal cell lacking oligosaccharides on the external surface of its plasma membrane would likely be impaired in which function?

In the years since the proposal of the fluid mosaic model of the cell membrane, which of the following observations has been added to the model?

A protein that spans the phospholipid bilayer one or more times is

The cell membranes of Antarctic ice fish might have which of the following adaptations?

In a paramecium, cell surface integral membrane proteins are synthesized

Cell membranes are asymmetrical. Which of the following is the most likely explanation?

Why are lipids and proteins free to move laterally in membranes?

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

Which of the following is a characteristic feature of a carrier protein in a plasma membrane?

Which of the following would likely move through the lipid bilayer of a plasma membrane most rapidly?

Water passes quickly through cell membranes because

Which of the following statements correctly describes the normal tonicity conditions for typical plant and animal cells?

When a plant cell, such as one from a peony stem, is submerged in a very hypotonic solution, what is likely to occur?

In which of the following would there be the greatest need for osmoregulation?

Which of the following membrane activities require energy from ATP hydrolysis?

The phosphate transport system in bacteria imports phosphate into the cell even when the concentration of phosphate outside the cell is much lower than the cytoplasmic phosphate concentration. Phosphate import depends on a pH gradient across the membrane-more acidic outside the cell than inside the cell. Phosphate transport is an example of

What is the voltage across a membrane called?

The sodium-potassium pump is called an electrogenic pump because it

The movement of potassium into an animal cell requires

Ions diffuse across membranes through specific ion channels

Which of the following would increase the electrochemical potential across a membrane?

The sodium-potassium pump in animal cells requires cytoplasmic ATP to pump ions across the plasma membrane. When the proteins of the pump are first synthesized in the rough ER, what side of the ER membrane will the ATP binding site be on?

An organism with a cell wall would most likely be unable to take in materials through

The difference between pinocytosis and receptor-mediated endocytosis is that