HESI A2 Practice Test Biology

Correct Answer: B

Rationale: The correct answer is B: Golgi apparatus. The Golgi apparatus is responsible for modifying, sorting, and packaging proteins and lipids from the endoplasmic reticulum for transport throughout the cell. It receives materials from the ER, processes them, and then directs them to their final destinations. Ribosomes (choice A) are responsible for protein synthesis, lysosomes (choice C) are involved in digestion and waste removal, and vacuoles (choice D) are storage organelles. Therefore, B is the correct answer as it specifically functions in the transportation of materials within the cell.

Correct Answer: B

Rationale: The correct answer is B: oxygen. Oxygen is not a product of the Krebs cycle; it is used as the final electron acceptor in the electron transport chain. Carbon dioxide (A) is a product of the Krebs cycle, produced during decarboxylation reactions. Adenosine triphosphate (ATP) (C) and energy carriers (D) such as NADH and FADH2 are also products of the Krebs cycle, as they are generated through the oxidation of substrates. Oxygen's role is crucial for the efficient functioning of aerobic respiration, but it is not a direct product of the Krebs cycle.

Correct Answer: D

Rationale: The correct answer is D: Nucleus. The nucleus contains the genetic material of the cell, which is stored in the form of DNA. It controls the cell's activities and serves as the command center. The Golgi apparatus (A) is involved in processing and packaging proteins, the ribosome (B) is responsible for protein synthesis, and the endoplasmic reticulum (C) is involved in protein synthesis and lipid metabolism. The nucleus is unique in its role as the organelle that houses the cell's genetic information.

Correct Answer: A

Rationale: The second part of an organism's scientific name is the species. In binomial nomenclature, developed by Carl Linnaeus, the scientific name consists of two parts: the genus and the species. The genus is the broader category that encompasses multiple species, while the species is the specific name unique to that particular organism within the genus. Therefore, the correct answer is A: species. Option B: phylum is incorrect as it is a higher taxonomic rank above the genus and species. Option C: population is incorrect as it refers to a group of organisms of the same species in a particular area. Option D: kingdom is incorrect as it is the highest taxonomic rank, encompassing all living organisms categorized into five kingdoms.

Correct Answer: D

Rationale: The correct answer is D because DNA controls the synthesis of enzymes, which are essential for carrying out metabolic activities in the cell. Enzymes are biological catalysts that regulate chemical reactions in the cell. DNA contains the genetic information needed to produce specific enzymes through the process of transcription and translation. Enzymes play a crucial role in breaking down nutrients, synthesizing molecules, and regulating metabolic pathways. A: DNA does not initiate cellular mitosis; that is controlled by other molecules. B: DNA is not responsible for providing cell wall stability; that is primarily the role of the cell wall structure itself. C: DNA is not directly involved in increasing glucose absorption; that is regulated by other mechanisms such as insulin signaling.