HESI A2 Biology 2024

Correct Answer: A

Rationale: During anaphase, the correct answer is A because it is the phase where chromosomes move to opposite ends of the spindle. This separation ensures that each new cell receives a complete set of chromosomes. Choice B is incorrect because nuclear membrane and nucleoli disintegrate during prophase, not anaphase. Choice C is incorrect as chromatids line up at the center of the spindle during metaphase. Choice D is incorrect as the nuclear membrane and nucleoli do not form during anaphase but rather re-form during telophase.

Correct Answer: D

Rationale: The correct answer is D: Citric acid. Citric acid is not a component of DNA nucleotides. A DNA nucleotide consists of a simple sugar (deoxyribose), a nitrogen base (adenine, thymine, cytosine, or guanine), and a phosphate group. Citric acid is not part of the structure of DNA; it is a component of the citric acid cycle in cellular respiration. Therefore, it is not found in the nucleotide of DNA. The other choices (A, B, and C) are all components that make up a DNA nucleotide, making them incorrect options.

Correct Answer: A

Rationale: The correct answer is A: Blue. Blue light is essential for photosynthesis as it is absorbed by chlorophyll, the pigment that drives the process. Blue light helps in vegetative growth and overall plant development. Yellow, green, and orange lights are not as effective as they are not as readily absorbed by plants for photosynthesis. Yellow and green lights do not provide the necessary energy for plant growth, while orange light is less efficient in promoting photosynthesis compared to blue light. Therefore, blue light is the most effective choice for growing green plants indoors.

Correct Answer: D

Rationale: The correct answer is D (46). Humans have 23 pairs of homologous chromosomes, totaling 46 chromosomes. Each pair consists of one chromosome from each parent. Choices A (13), B (23), and C (26) are incorrect as they do not represent the total number of pairs of homologous chromosomes in humans. A and C do not reflect the correct total number of chromosomes, while B only specifies the number of individual chromosomes, not pairs. Therefore, option D is the correct choice because it accurately represents the total number of homologous chromosome pairs in humans.

Correct Answer: A

Rationale: The correct answer is A: Centriole. Centrioles are cylindrical structures found in animal cells that play a key role in cell division by organizing microtubules of the mitotic spindle. Plant cells lack centrioles and instead use their microtubule organizing centers for cell division. B: Cytoplasm is incorrect as it is a universal component of all cells, including both animal and plant cells. C: Vacuole is incorrect as it is a large, membrane-bound organelle present in plant cells for storage, structure, and support. D: Golgi apparatus is incorrect as it is present in both animal and plant cells and is responsible for packaging and processing proteins for secretion.