HESI A2
Biology HESI A2 Practice Test
1. Which of the following describes the situation where one allele takes a different form from another in a gene?
- A. phenotype
- B. heterozygous
- C. homolog
- D. homozygous
Correct answer: B
Rationale: Heterozygous is the term used to describe the genotype of an individual with two different alleles for a specific gene. In this case, one allele takes a different form from another, resulting in genetic diversity and variation in trait expression. The other choices are incorrect: 'phenotype' refers to the observable traits of an organism, 'homolog' typically refers to chromosomes that are similar in structure, and 'homozygous' describes the genotype where both alleles for a gene are the same.
2. Which organelle is responsible for detoxifying harmful substances in the cell?
- A. Endoplasmic Reticulum
- B. Lysosomes
- C. Peroxisomes
- D. Golgi Apparatus
Correct answer: C
Rationale: The correct answer is C, Peroxisomes. Peroxisomes are responsible for detoxifying harmful substances in the cell by breaking down fatty acids and producing hydrogen peroxide. This process helps protect the cell from damage caused by toxic substances. Choice A, Endoplasmic Reticulum, is involved in protein and lipid synthesis, not detoxification. Choice B, Lysosomes, contain enzymes for digestion and waste removal, not primarily detoxification. Choice D, Golgi Apparatus, is responsible for modifying, sorting, and packaging proteins for secretion, not detoxification.
3. What process do cells in the tip of a plant’s root undergo to increase in number?
- A. Meiosis
- B. Cytokinesis
- C. Fractioning
- D. Mitosis
Correct answer: D
Rationale: Cells in the tip of a plant's root undergo the process of mitosis to increase in number. Mitosis is a type of cell division that results in two daughter cells with the same number of chromosomes as the parent cell. This process allows for growth and maintenance of tissues in plants by producing new cells through division. Choice A, Meiosis, is incorrect as meiosis is a type of cell division that reduces the number of chromosomes in cells to produce gametes. Choice B, Cytokinesis, is incorrect as it is the division of the cytoplasm following cell division. Choice C, Fractioning, is not a biological process related to cell division.
4. What is the classification of organisms into different categories based on their physical characteristics and presumed natural relationship?
- A. Biology
- B. Taxonomy
- C. Grouping
- D. Nomenclature
Correct answer: B
Rationale: Taxonomy is the correct answer. Taxonomy is the branch of biology that deals with the classification of organisms into different categories based on their physical characteristics and presumed natural relationship. It involves naming and categorizing organisms into hierarchical groups to show their evolutionary relationships. Choice A, 'Biology,' is incorrect as it is the broader field of science that encompasses the study of living organisms. Choice C, 'Grouping,' is incorrect as it is a general term that does not specifically refer to the systematic classification of organisms. Choice D, 'Nomenclature,' is incorrect as it refers to the system of naming organisms rather than the classification based on physical characteristics and natural relationships.
5. Which organelle organizes protein synthesis?
- A. mitochondrion
- B. nucleus
- C. ribosome
- D. vacuole
Correct answer: C
Rationale: Ribosomes are the organelles responsible for organizing protein synthesis. They are the protein factories of the cell, where amino acids are linked together to form proteins. Mitochondria are known as the powerhouse of the cell, responsible for energy production. The nucleus contains the cell's genetic material but does not directly organize protein synthesis. Vacuoles are responsible for storage and maintaining the cell's turgidity.
Similar Questions
Access More Features
HESI A2 Basic
$99/ 30 days
- 3,000 Questions with answers
- 30 days access
HESI A2 Premium
$149.99/ 90 days
- Actual HESI A2 Questions
- 3,000 questions with answers
- 90 days access