AP Cell Membranes (7)

AP Cell Membranes (7)

by Lauren Ayers

Multiple Choice

Which of the following statements best describes a characteristic feature of integral membrane proteins?

• They are hydrophilic.

• They are hydrophobic.

• They are amphipathic, with at least one hydrophobic region.

• They are localized to the interior surface of the membrane.

Multiple Choice

Which of the following statements best describes the structure of a membrane based on the fluid mosaic model?

• The membrane is composed of a fluid bilayer of phospholipids between two layers of hydrophilic proteins.

• The membrane is composed of a single layer of fluid phospholipids between two layers of hydrophilic proteins.

• The membrane is composed of a mosaic of fluid polysaccharides and amphipathic proteins

• The membrane is composed of a fluid bilayer of phospholipids with embedded amphipathic proteins.

Multiple Choice

Cell membranes have distinct inside and outside faces. Which of the following statements is the most plausible explanation for the asymmetrical nature of the two layers of the membrane?

• Cell membranes form a border between adjacent cells in tightly packed tissues such as epithelium.

• Cell membranes communicate signals between different cell types.

• The two layers of a cell membrane face different environments and carry out different functions.

• Proteins only function on the cytoplasmic side of the cell membrane.

Multiple Choice

Which of the following types of molecules will diffuse through a cell membrane most readily?

• large hydrophobic molecules

• small hydrophobic molecules

• large polar molecules

• small ionic molecules

Multiple Choice

Which of the following types of molecules are least likely to diffuse through the phospholipid bilayer of a cell membrane?

• large hydrophobic molecules

• small hydrophobic molecules

• carbon dioxide

• small ions

Multiple Choice

Which of the following statements best describes a characteristic feature of a carrier protein in a plasma membrane?

• it exhibits specificity for a particular type of molecule.

• It requires the expenditure of cellular energy to function.

• It works against a concentration gradient.

• It has no hydrophobic regions.

Multiple Choice

Which type of passive diffusion exponentially increases the rate of diffusion at first, but then levels off?

• active transport

• facilitated diffusion

• simple diffusion

Multiple Choice

Assuming that the purple molecules are too large to pass through the membrane, what would happen to the water level as a result of osmosis?

• The water level would rise on the A side

• The water level would rise on the B side

• The water level would remain constant

• The water level would drop on the A side.

Multiple Choice

This egg has shrunk, what type of solution was it placed in?

• hypotonic solution

• hypertonic solution

• isotonic solution

Multiple Choice

What type of solution is this cell in?

• Isotonic
• Hypertonic
• Hypotonic
• diffused

Multiple Choice

What type of solution allows water to enter the plant cell?

• hypotonic solution
• hypertonic solution
• isotonic solution
• active transport

Multiple Choice

What type of solution is this cell in?

• Isotonic
• Hypertonic
• Hypotonic
• diffused

Multiple Choice

In an isotonic solution which way will the water flow

• it will not flow at all

• it will flow into the cell

• it will flow both ways at equal rates

• out of the cell

Multiple Choice

During osmosis

• water moves from high to low concentration

• large or oddly shaped molecules move across a cell membrane

• water moves when energy is used

• proteins are built

Multiple Choice

What is the difference between active and passive transport?

• Active does not need energy and passive uses ATP (energy)
• Active uses ATP (energy) and passive does not need energy
• Active stores transport proteins and passive releases 
• Active uses hormones and passive does not 

Multiple Choice

The sodium-potassium pumps requires energy to move ions across the cell membrane against their concentration gradient so it is a type of

• active transport
• osmosis
• diffusion
• facilitated diffusion

Multiple Choice

Which of the following membrane activities requires energy from ATP?

• Facilitated diffusion of chloride ions through a chloride channel.

• Movement of Na⁺ ions from lower concentration in a mammalian cell to a higher concentration in the extracellular fluid.

• Movement of glucose molecules into a bacteria cell from a medium containing a higher concentration of glucose than inside the cell.

• Movement of carbon dioxide out of a paramecium.

Multiple Choice

White blood cells engulf bacteria using _______________.

• phagocytosis

• pinocytosis

• osmosis

• receptor-mediated exocytosis