Which of the following best describes facilitated diffusion?

A. Movement of molecules against a concentration gradient using energy
B. Movement of molecules from a region of higher concentration to a lower concentration without energy
C. Movement of molecules from a region of lower concentration to higher concentration using protein channels
D. Movement of molecules from a region of higher concentration to lower concentration using protein channels

What will happen to a plant cell placed in a hypertonic solution?

A. The cell will swell due to water influx
B. The cell will shrink due to water efflux
C. The cell will remain unchanged
D. The cell will burst due to water influx

Which pump is responsible for maintaining the electrochemical gradient across the cell membrane?

A. Proton pump
B. Calcium pump
C. Sodium-potassium pump
D. Glucose pump

Which form of endocytosis involves the ingestion of liquid into the cell?

A. Phagocytosis
B. Pinocytosis
C. Receptor-mediated endocytosis
D. Exocytosis

Exocytosis is crucial for which of the following processes?

A. Ingesting bacteria
B. Releasing neurotransmitters
C. Ingesting fluids
D. Transporting ions across the membrane

a) Explain the process of diffusion and discuss the factors that affect the rate of diffusion across the cell membrane. [4]

b) Define and differentiate between hypertonic, hypotonic, and isotonic solutions, and describe their effects on plant cells in terms of turgor pressure. [4]

a) Describe the mechanism of facilitated diffusion and explain how it differs from simple diffusion. [3]

b) Discuss the role and mechanism of the sodium-potassium pump in maintaining cellular homeostasis. [4]

a) Explain the process of osmosis and discuss its significance in maintaining water balance in cells. [3]

b) Describe the process of receptor-mediated endocytosis and discuss its role in nutrient uptake. [4]

a) Discuss the kinetic energy of molecules in relation to the process of diffusion. How does temperature influence this process? [3]

b) Define water potential and explain its role in osmosis, particularly in plant cells. [3]

c) Describe the mechanism of cotransport in cells and explain how energy derived from ATP is utilised in this process. [4]

a) Explain the principle of equilibrium in the context of diffusion. How does the concentration gradient affect the attainment of equilibrium? [3]

b) Discuss the role of proton pumps in maintaining cellular pH and electrochemical gradient. [4]

c) Describe the process of pinocytosis and explain its significance in cellular nutrient uptake. [3]