Gaokao Exam Gaokao Biology: Cell Biology and Metabolism 4

Question 1

The net equation for glycolysis converting one glucose molecule is BEST represented as:

Accepted Answer

C₆H₁₂O₆ → 2C₃H₄O₃ + 4H + 2 ATP (net)

Answer

Glycolysis produces 2 pyruvate (C₃H₄O₃), 2 net ATP, 2 NADH, and 2 water molecules from one glucose in the cytoplasm without oxygen.

Question 2

Cholesterol molecules in the cell membrane serve to:

Accepted Answer

Regulate membrane fluidity at varying temperatures

Answer

Cholesterol intercalates between phospholipids; at high temperatures it restricts movement (decreasing fluidity), while at low temperatures it prevents packing (maintaining fluidity).

Question 3

In the electron transport chain, the final electron acceptor is:

Accepted Answer

Molecular oxygen (O₂)

Answer

Oxygen is the terminal electron acceptor in aerobic respiration; it accepts electrons and combines with H⁺ to form water at Complex IV.

Question 4

Which cell structure is responsible for modifying, sorting, and packaging proteins for secretion?

Accepted Answer

Golgi apparatus

Answer

The Golgi apparatus receives proteins from the ER in vesicles, modifies them (e.g., glycosylation), sorts them, and packages them into secretory vesicles.

Question 5

When a plant cell is placed in a hypertonic solution, what occurs?

Accepted Answer

Plasmolysis occurs as water leaves the cell by osmosis

Answer

In a hypertonic solution, water moves out of the cell by osmosis, causing the vacuole to shrink and the plasma membrane to pull away from the cell wall (plasmolysis).

Gaokao Exam Practice Test

Gaokao Exam Practice Test

Gaokao Exam Gaokao Biology: Cell Biology and Metabolism 4