AP Bio-Cell TRansport

Open Ended

Why is the movement of molecules across cell membranes essential for maintaining homeostasis in living organisms?

Multiple Choice

What is the primary function of the cell membrane?

• To provide energy for the cell

• To control the movement of substances in and out of the cell

• To produce proteins

• To store genetic information

Multiple Choice

Which of the following best describes the function of the cell membrane as shown in the diagram?

• It controls the movement of substances in and out of the cell.

• It produces energy for the cell.

• It stores genetic information.

• It synthesizes proteins.

Open Ended

Describe how the structure of the cell membrane contributes to its function in controlling transport.

Multiple Choice

What is required for passive transport to occur across a cell membrane?

• A concentration gradient

• Energy from ATP

• Carrier proteins only

• Active pumping mechanisms

Multiple Select

Which of the following molecules can diffuse directly through the phospholipid bilayer without the help of membrane proteins?

• Oxygen (O2)

• Carbon Dioxide (CO2)

• Glucose

• Sodium ions (Na+)

Multiple Choice

Which of the following statements best explains the specificity of channel proteins in the cell membrane?

• Each channel protein allows only certain molecules or ions to pass through.

• Channel proteins allow all molecules to pass freely.

• Channel proteins only transport water molecules.

• Channel proteins require energy to function.

Open Ended

Explain how the sodium-potassium pump uses energy to move ions against their concentration gradients.

Multiple Select

Which of the following are true about the sodium-potassium pump?

• It moves sodium ions out of the cell.

• It moves potassium ions into the cell.

• It requires ATP to function.

• It transports glucose across the membrane.

Multiple Choice

What is the main function of co-transporters in the cell membrane?

• Transport multiple molecules simultaneously

• Break down large molecules

• Produce ATP

• Allow only water to pass through

Open Ended

Describe the differences between phagocytosis, pinocytosis, and receptor-mediated endocytosis as forms of bulk transport.

Multiple Choice

Which process is responsible for the release of molecules from cell A to cell B as shown in the diagram?

• Endocytosis

• Exocytosis

• Osmosis

• Diffusion

Multiple Select

Which of the following statements about hypertonic, hypotonic, and isotonic solutions are correct?

• Hypertonic solutions have more solute and less solvent.

• Hypotonic solutions have less solute and more solvent.

• Isotonic solutions have equal concentrations of solute and solvent.

• The solvent in these comparisons is always water.

Open Ended

Explain how tonicity affects the movement of water and solutes across cell membranes and describe the resulting effects on cell physiology.

Multiple Choice

What happens to a plant cell when placed in a hypotonic solution?

• It becomes plasmolyzed

• It becomes flaccid

• It becomes turgid

• It bursts

Multiple Choice

Which of the following statements best describes water potential (Ψ)?

• It measures how likely water will move in or out of a solution.

• It measures the concentration of solutes in a solution.

• It measures the temperature of a solution.

• It measures the volume of water in a cell.

Open Ended

Explain how both pressure potential and solute potential contribute to the overall water potential of a system. Use the equation Ψ = Ψp + Ψs in your explanation.

Multiple Choice

Given the sample problem, which solution (A, B, or C) will gain the most water if placed in pure water at the indicated temperature?

• A: Sucrose, 2M, 298K

• B: NaCl, 1M, 290K

• C: Glucose, 1M, 300K

• All will gain the same amount of water

Open Ended

What is one question you still have about the mechanisms of cellular transport or the role of the cell membrane?