Chapter 4 test

Which of the following substances can freely pass through the phospholipid bilayer of the cell membrane?

• water

• calcium ion

• oxygen

• glucose

Which of the following is/are needed for diffusion to occur?

(1) a concentration gradient

(2) a differentially permeable membrane

(3) supply of ATP

• (1) only

• (2) only

• (1) and (2) only

• (1), (2) and (3)

Which processes of moving substances across the cell membrane would result in equilibrium?

(1) diffusion

(2) osmosis

(3) active transport

• (1) and (2) only

• (2) and (3) only

• (1) and (3) only

• (1), (2) and (3)

The graph shows the rate of movement of two substances, X and Y, across the cell membrane. X and Y move across the membrane through different mechanisms.

Which of the following can be deduced from the graph?

• Substance X is lipid-soluble.

• The transport of substance X involves carrier proteins.

• The rate of transport of substance Y is not affected by temperature.

• The rate of transport of substance Y will always be lower than that of substance X.

The diagram shows a set-up demonstrating osmosis. The dialysis tubing used is impermeable to sucrose molecules.

Which of the options correctly identifies solutions A and B, and the corresponding change in the volume of the dialysis tubing?

• A

• B

• C

• D

The diagram shows the appearance of a plant cell immersed in an isotonic solution.

Which of the options correctly represents the appearance of the plant cell immersed in a hypertonic solution?

• A

• B

• C

• D

Which of the following is an example of passive movement across the cell membrane?

• phagocytes engulfing a bacterium

• Paramecium in a fresh water stream gaining water from the surroundings

• some cells of the small intestine excreting mucus into the gut lumen

• Amoeba feeding on algae

Which of the following processes only occurs in living cells?

• diffusion

• evaporation

• osmosis

• phagocytosis

The diagram shows the initial distribution of sucrose and water molecules.

Which of the options best represents the movement of molecules at the equilibrium stage? (The movement of water molecule is indicated by the arrows)

• A

• B

• C

• D

The diagram shows two processes of transport of substances across the cell membrane.

Identify processes X and Y.

• A

• B

• C

• D