HESI A2 Biology Practice Test

Correct Answer: D

Rationale: The correct answer is D because mitosis is essential for the growth and repair of body tissues. During mitosis, a cell divides to produce two identical daughter cells with the same genetic information as the parent cell. This process is crucial for replacing damaged or dead cells, allowing for growth and tissue repair. A is incorrect because mitosis does not involve the fusion of male and female gametes, which is a process called fertilization. B is incorrect because mitosis actually maintains genetic consistency within a species by producing genetically identical cells. C is incorrect because mitosis typically produces cells that are very similar to the parent cell, ensuring the preservation of genetic information and function.

Correct Answer: C

Rationale: The correct answer is C because plant cells have a rigid cell wall that prevents them from forming a contractile ring during cell division. The cell wall provides structural support, making it challenging for plant cells to constrict and pinch apart like animal cells. This rigidity limits the flexibility needed for the contractile ring to form and function effectively. Plant cells primarily rely on other mechanisms such as cell plate formation for division. Choices A and B are incorrect as they do not address the specific structural difference between plant and animal cells. Choice D is incorrect as it does not provide any relevant information on the topic.

Correct Answer: A

Rationale: The correct answer is A: fat-soluble hormones. Fat-soluble hormones can diffuse through the cell membrane due to their lipophilic nature. Once inside the cell, they can bind to receptors located in the cytoplasm or nucleus to initiate a chemical response. This process allows fat-soluble hormones to directly affect gene expression and protein synthesis within the target cell. In contrast, choices B, C, and D (amino acid derivatives, hydrophilic, and water-soluble hormones) cannot diffuse through the cell membrane and typically bind to receptors on the cell surface to trigger a signaling cascade.

Correct Answer: A

Rationale: Epithelial cells are correct to be classified as polarized because they have distinct apical and basal surfaces. The apical surface faces the external environment or a body cavity, while the basal surface is anchored to the underlying connective tissue. This polarity is essential for the specialized functions of epithelial cells, such as absorption, secretion, and transportation. Therefore, choice A is the correct answer. Choices B and C are incorrect because epithelial cells are not neutral and are not necessarily larger than other cells. Choice D is incorrect because epithelial cells do have unique characteristics that differentiate them from other cell types.

Correct Answer: A

Rationale: The correct answer is A: Dominant. When a genotype consists of a dominant and a recessive allele, the dominant allele will determine the phenotype. This is because the presence of a dominant allele masks the expression of the recessive allele. In this case, the dominant allele will be expressed phenotypically, resulting in a trait that is like the dominant allele. Choices B, C, and D are incorrect because in this scenario, the dominant allele will be the one that is visibly expressed, not the recessive allele, both alleles, or neither allele.