HESI RN
Biology Practice Test
1. Which of the following organelles is the site of cellular respiration?
- A. Nucleus
- B. Mitochondria
- C. Lysosomes
- D. Ribosomes
Correct answer: B
Rationale: The correct answer is B: Mitochondria. Mitochondria are known as the powerhouse of the cell because they generate most of the cell's supply of ATP through cellular respiration. The other organelles listed, such as the nucleus (choice A), lysosomes (choice C), and ribosomes (choice D), do not play a direct role in cellular respiration. The nucleus contains genetic material, lysosomes are involved in digestion and waste removal, and ribosomes are responsible for protein synthesis.
2. A water molecule contains two types of atoms that are covalently bonded. Which of the following makes up a water molecule?
- A. One hydrogen atom and one oxygen atom
- B. One hydrogen atom and two oxygen atoms
- C. Two hydrogen atoms and two oxygen atoms
- D. Two hydrogen atoms and one oxygen atom
Correct answer: D
Rationale: The correct answer is D: Two hydrogen atoms and one oxygen atom. A water molecule consists of two hydrogen atoms covalently bonded to one oxygen atom. This forms a stable structure known as H2O. Choice A is incorrect as water molecule contains two hydrogen atoms. Choices B and C are incorrect as they do not reflect the correct composition of a water molecule.
3. Which of the following is a lipid that is a membrane component and a precursor to significant hormones?
- A. Nucleic acids
- B. Proteins
- C. Carbohydrates
- D. Steroids
Correct answer: D
Rationale: The correct answer is D, Steroids. Steroids are a type of lipid that function as essential components of cell membranes and serve as precursors for significant hormones like estrogen and testosterone. Nucleic acids (choice A) are not lipids but are molecules like DNA and RNA that store genetic information. Proteins (choice B) and carbohydrates (choice C) are biomolecules but are not lipids and do not serve as precursors for hormones or membrane components.
4. Prophase is the first stage of mitosis. Which of the following best describes chromosomes during this stage?
- A. They are gathered on either side of the separating cell
- B. They are all aligned along the metaphase plate
- C. They are attached to the spindle
- D. They are visibly separate
Correct answer: D
Rationale: The correct answer is D. During prophase, the chromosomes condense and become visible as distinct structures under a microscope. Choice A is incorrect as chromosomes are not gathered on either side of the separating cell during prophase. Choice B is incorrect because chromosomes align along the metaphase plate during the subsequent stage, metaphase. Choice C is incorrect as chromosomes become attached to the spindle fibers during prometaphase, the stage following prophase.
5. During which stage of mitosis do the chromosomes gather on either side of the separating cell?
- A. Metaphase
- B. Telophase
- C. Anaphase
- D. Prophase
Correct answer: B
Rationale: The correct answer is B, Telophase. During telophase, the chromosomes gather at opposite poles of the cell as the nuclear envelopes start to form around them, indicating the end of cell division. Choices A, C, and D are incorrect because during metaphase, the chromosomes align in the middle of the cell; in anaphase, the chromosomes separate and move towards opposite poles; and in prophase, the chromosomes condense and the nuclear envelope breaks down, respectively.
Similar Questions

Access More Features
HESI RN Basic
$69.99/ 30 days
- 50,000 Questions with answers
- All HESI courses Coverage
- 30 days access @ $69.99
HESI RN Premium
$149.99/ 90 days
- 50,000 Questions with answers
- All HESI courses Coverage
- 30 days access @ $149.99