Gaokao Exam Gaokao Biology: Cell Biology and Metabolism 3

Question 1

The process by which cells engulf large particles or other cells by membrane folding is called:

Accepted Answer

Phagocytosis

Answer

Phagocytosis ('cell eating') involves pseudopods engulfing large particles into a phagosome, which then fuses with lysosomes for digestion.

Question 2

Which molecule carries amino acids to the ribosome during translation?

Accepted Answer

tRNA

Answer

Transfer RNA (tRNA) molecules have anticodons that recognize mRNA codons and carry the corresponding amino acid to the ribosome.

Question 3

Photosystem I (PSI) primarily absorbs light at a peak wavelength of 700 nm and its main function is to:

Accepted Answer

Reduce NADP⁺ to NADPH

Answer

PSI uses light energy to transfer electrons to ferredoxin, which ultimately reduces NADP⁺ to NADPH for use in the Calvin cycle.

Question 4

Which of the following is a characteristic feature distinguishing prokaryotic cells from eukaryotic cells?

Accepted Answer

Absence of membrane-bound nucleus

Answer

Prokaryotic cells lack a membrane-bound nucleus; their genetic material exists as a nucleoid region in the cytoplasm.

Question 5

The Km (Michaelis constant) of an enzyme is BEST described as:

Accepted Answer

The substrate concentration at which reaction rate is half of Vmax

Answer

Km represents the substrate concentration at which the reaction velocity is half of Vmax and is an indicator of the enzyme's affinity for its substrate.

Gaokao Exam Practice Test

Gaokao Exam Practice Test

Gaokao Exam Gaokao Biology: Cell Biology and Metabolism 3