HESI A2
HESI A2 Biology Practice Test 2024
1. What propels the cell forward?
- A. Microfilaments
- B. Propulsion
- C. Cilia
- D. Flagella
Correct answer: B
Rationale: Propulsion, not microfilaments, cilia, or flagella, is what drives the cell forward. Propulsion is the force or process that propels the cell forward and allows it to move within its environment. Microfilaments are involved in cell structure, cilia are small hair-like structures for movement, and flagella are tail-like structures used for cell propulsion in some organisms.
2. How many different types of nucleotides are there in DNA?
- A. one
- B. two
- C. four
- D. eight
Correct answer: C
Rationale: The correct answer is 'C: four.' DNA is composed of four different types of nucleotides: adenine, thymine, guanine, and cytosine. These nucleotides pair up in specific combinations to form the genetic code. Choices 'A: one,' 'B: two,' and 'D: eight' are incorrect because DNA consists of a set of four distinct nucleotides, not one, two, or eight.
3. How many phases are there in the process of mitosis?
- A. 2
- B. 3
- C. 4
- D. 5
Correct answer: C
Rationale: The correct answer is C: '4'. Mitosis consists of four phases: prophase, metaphase, anaphase, and telophase. These phases are crucial in the orderly division of the cell's genetic material. Choice A is incorrect because mitosis is a more complex process involving multiple phases. Choice B is incorrect as it is one phase short of the total phases in mitosis. Choice D is incorrect as mitosis does not consist of five phases.
4. 72 chromosomes undergo meiosis. How many chromosomes will be in each gamete?
- A. 18
- B. 36
- C. 72
- D. 144
Correct answer: A
Rationale: During meiosis, the number of chromosomes is halved in each gamete. Since 72 chromosomes undergo meiosis, each gamete will contain half of that number, which is 36 chromosomes. Therefore, the correct answer is 18 chromosomes in each gamete. Choice B (36 chromosomes) is incorrect because it represents the total number of chromosomes that undergo meiosis, not the number in each gamete. Choice C (72 chromosomes) is incorrect as it represents the initial number of chromosomes, not the number in each gamete after meiosis. Choice D (144 chromosomes) is incorrect as it doubles the initial number of chromosomes, which is not the outcome of meiosis.
5. What happens during anaphase?
- A. Chromosomes move to opposite ends of the spindle.
- B. Nuclear membrane and nucleoli disintegrate.
- C. Chromatids line up at the center of the spindle.
- D. Nuclear membrane and nucleoli form.
Correct answer: A
Rationale: During anaphase, the sister chromatids, joined at the centromere, separate and move towards opposite ends of the spindle apparatus. This movement ensures that each daughter cell receives an identical set of chromosomes. Choice B is incorrect as the disintegration of the nuclear membrane and nucleoli occurs during prophase. Choice C is incorrect as chromatids align at the center of the spindle during metaphase, not anaphase. Choice D is incorrect as the formation of the nuclear membrane and nucleoli occurs during telophase, not anaphase.
Similar Questions
Access More Features
HESI A2 Basic
$49/ 30 days
- 3,000 Questions with answers
- 30 days access
HESI A2 Premium
$99/ 90 days
- Actual HESI A2 Questions
- 3,000 questions with answers
- 90 days access