HESI A2
Biology HESI A2 Practice Exam
1. Which of the following is a tertiary consumer?
- A. Owl
- B. Shrew
- C. Grasshopper
- D. Wheat
Correct answer: A
Rationale: The correct answer is A, Owl. Tertiary consumers are organisms that feed on secondary consumers, which, in turn, feed on primary consumers. Owls are considered tertiary consumers because they primarily feed on animals such as rodents, which are secondary consumers. Shrew (choice B) is a secondary consumer, feeding on insects and worms, placing it at a lower trophic level than the owl. Grasshopper (choice C) is a primary consumer, feeding on plants. Wheat (choice D) is not a consumer in the food chain but a plant.
2. What is the role of ribosomes in the cell?
- A. Break down cellular waste
- B. Organize cellular division
- C. Synthesize proteins
- D. Provide cellular structure
Correct answer: C
Rationale: The correct answer is C: Synthesize proteins. Ribosomes are responsible for protein synthesis by linking amino acids together. Choice A is incorrect because ribosomes do not break down cellular waste. Choice B is incorrect as ribosomes do not organize cellular division. Choice D is incorrect because ribosomes do not provide cellular structure.
3. Duchenne muscular dystrophy is a recessive sex-linked trait carried on the X chromosome. In an example of an unaffected father and a female carrier who have two daughters and two sons, which is the predicted outcome?
- A. Both daughters will carry the disease.
- B. Both sons will carry the disease.
- C. One daughter may have the disease.
- D. One son may have the disease.
Correct answer: C
Rationale: Duchenne muscular dystrophy is a recessive sex-linked trait carried on the X chromosome. Since the father is unaffected and does not carry the disease, he must have a normal X chromosome. The mother is a carrier, which means she has one normal X chromosome and one X chromosome with the disease allele. The daughters will inherit one X chromosome from each parent; one would be normal, and the other has a chance of carrying the disease allele. So, there is a 50% chance that one daughter may have the disease, as she could inherit the X chromosome with the disease allele. The sons will inherit the Y chromosome from the father and the X chromosome from the mother, so they will not be affected by the disease. Therefore, the predicted outcome is that one daughter may have the disease, while the sons will not carry the disease. This rules out choices A, B, and D.
4. Which of the following organelles is responsible for producing ATP in cells?
- A. Nucleus
- B. Mitochondrion
- C. Chloroplast
- D. Lysosome
Correct answer: B
Rationale: The correct answer is 'Mitochondrion.' Mitochondria are known as the powerhouse of the cell and are responsible for producing ATP, the energy currency of the cell. The nucleus is responsible for storing genetic material and controlling cell activities, not for ATP production. Chloroplasts are found in plant cells and are responsible for photosynthesis, not ATP production. Lysosomes are involved in digestion and waste removal, not ATP production.
5. Which of the following arrangement is seen in the plasma membrane?
- A. Lipids with embedded proteins
- B. An outer lipid layer and an inner lipid layer
- C. Proteins embedded in lipid bilayer
- D. Altering protein and lipid layers
Correct answer: C
Rationale: The correct arrangement seen in the plasma membrane is proteins embedded in the lipid bilayer. The plasma membrane is composed of a lipid bilayer with embedded proteins. These proteins perform various functions such as transport, signaling, and structural support within the cell membrane. This arrangement allows for the selective permeability of the membrane and facilitates communication between the cell and its environment. Choices A, B, and D are incorrect because the primary arrangement in the plasma membrane involves proteins being embedded in the lipid bilayer, not lipids with embedded proteins, an outer and inner lipid layer, or altering protein and lipid layers.
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