prokaryotic cells lack which of the following

HESI RN

Biology Practice Test

1. Which of the following do prokaryotic cells lack?

A. A cell membrane
B. Genetic material
C. Cytoplasm
D. Membrane-bound organelles

Correct answer: D

Rationale: The correct answer is D: Prokaryotic cells lack membrane-bound organelles, such as mitochondria or a nucleus, distinguishing them from eukaryotic cells. Prokaryotic cells do have genetic material, a cell membrane, and cytoplasm. Choice A is incorrect because prokaryotic cells do have a cell membrane, which is essential for maintaining cell structure and regulating what enters and exits the cell. Choice B is incorrect because prokaryotic cells contain genetic material, typically in the form of a single circular chromosome. Choice C is incorrect because prokaryotic cells have cytoplasm, where various cellular activities take place.

2. Which organelle has the ability to hydrolyze fats, nucleic acids, proteins, and sugars?

A. Chloroplasts
B. Mitochondria
C. Lysosomes
D. Ribosomes

Correct answer: C

Rationale: The correct answer is C, Lysosomes. Lysosomes contain hydrolytic enzymes that are capable of breaking down various biomolecules such as fats, nucleic acids, proteins, and sugars. This organelle acts as the 'digestive system' of the cell. Choices A, B, and D are incorrect because chloroplasts are involved in photosynthesis, mitochondria are responsible for energy production, and ribosomes are responsible for protein synthesis, not the hydrolysis of biomolecules.

3. Water is a polar molecule that can be:

A. cohesive and corrosive
B. cohesive and adhesive
C. electrostatic and ionic
D. repellent and attractive

Correct answer: B

Rationale: Water is a polar molecule due to an uneven distribution of electrons, allowing it to form hydrogen bonds. This property makes water both cohesive (attracted to itself) and adhesive (attracted to other substances). Choice A is incorrect because water is not corrosive; rather, it is a solvent. Choices C and D are incorrect as they do not describe the cohesive and adhesive properties of water.

4. In which of the following does cellular respiration take place?

A. Golgi apparatus
B. Mitochondrion
C. Chloroplast
D. Ribosome

Correct answer: B

Rationale: The correct answer is B, Mitochondrion. Cellular respiration occurs in the mitochondria, where glucose is converted into energy through a series of metabolic processes. Choice A, Golgi apparatus, is incorrect as it is involved in modifying, sorting, and packaging proteins. Choice C, Chloroplast, is incorrect as it is the site of photosynthesis in plant cells, not cellular respiration. Choice D, Ribosome, is incorrect as it is responsible for protein synthesis, not energy production through cellular respiration.

5. During which stage of photosynthesis is solar energy converted to chemical energy?

A. During phosphate synthesis
B. During light reactions
C. During the Krebs cycle
D. During the Calvin cycle

Correct answer: B

Rationale: The correct answer is B, during the light reactions. During the light reactions of photosynthesis, solar energy is absorbed by chlorophyll and converted into chemical energy in the form of ATP and NADPH. Choice A is incorrect as phosphate synthesis does not involve the conversion of solar energy. Choice C, the Krebs cycle, is a part of cellular respiration, not photosynthesis. Choice D, the Calvin cycle, is responsible for fixing carbon dioxide into carbohydrates and does not involve the direct conversion of solar energy to chemical energy.