HESI A2 Biology Practice Test 2024

Correct Answer: B

Rationale: The correct answer is B: Communication. The cell membrane serves as a barrier that regulates the passage of materials in and out of the cell. It also plays a crucial role in cell communication by allowing the exchange of signals and molecules with the external environment and other cells. This communication is essential for coordinating various cellular processes and maintaining homeostasis. Other choices are incorrect: A: Energy production - This function is primarily carried out by organelles such as mitochondria and chloroplasts, not the cell membrane. C: Protein synthesis - Protein synthesis occurs in the ribosomes within the cell, not the cell membrane. D: Waste removal - While the cell membrane does play a role in waste removal by allowing certain materials to exit the cell, it is not its main function.

Correct Answer: B

Rationale: The correct answer is B: Eukaryotic. Animal cells are eukaryotic cells because they have a defined nucleus that houses the genetic material. This nucleus is surrounded by a membrane, along with other membrane-bound organelles like mitochondria and endoplasmic reticulum. Prokaryotic cells (Option A) lack a true nucleus and membrane-bound organelles. Plant cells (Option C) have similar characteristics to animal cells but also have additional features like a cell wall and chloroplasts. Bacterial cells (Option D) are prokaryotic cells and differ significantly from animal cells in structure and function.

Correct Answer: B

Rationale: The main component of blood plasma is water. Plasma is the liquid component of blood, making up about 55% of total blood volume. It serves as a carrier for various substances such as nutrients, waste products, hormones, and electrolytes. Water helps maintain blood volume, regulates body temperature, and facilitates the transport of essential components throughout the body. Proteins, red blood cells, and platelets are also present in blood plasma but are not the main component. Proteins play a role in clotting and immune function, red blood cells carry oxygen, and platelets aid in blood clotting. Water is the correct answer as it is the primary constituent of blood plasma.

Correct Answer: B

Rationale: The correct answer is B: Gametes. Meiosis is the process of cell division that produces gametes (sex cells) such as sperm and eggs. During meiosis, a diploid cell undergoes two rounds of division to produce four haploid gametes. Somatic cells (choice A) are non-reproductive cells in the body. Zygote (choice C) is a fertilized egg formed by the fusion of sperm and egg, not involved in meiosis. Diploid cells (choice D) have two sets of chromosomes and are the starting cells for meiosis, not the end products. Therefore, gametes are the specific cells involved in meiosis.

Correct Answer: C

Rationale: The correct answer is C: 4. Mitosis consists of four phases: prophase, metaphase, anaphase, and telophase. In prophase, chromosomes condense. In metaphase, chromosomes align at the cell equator. In anaphase, sister chromatids separate and move to opposite poles. In telophase, the nuclear envelope reforms. Choices A, B, and D are incorrect because mitosis is a complex process that involves more than 2 or 3 phases.