HESI A2
HESI A2 Biology 2024
1. How should a researcher test the hypothesis that practicing yoga reduces blood pressure?
- A. Record the blood pressure of one male and one female participant before and after participating in a yoga class.
- B. Divide 30 female participants into two groups with similar average blood pressure; test each participant’s blood pressure after participating in a yoga class.
- C. Divide 30 female participants into two groups with similar average blood pressure; have one group watch television for an hour while the other takes a yoga class, record each participant’s blood pressure after the hour. Repeat daily for two weeks.
- D. Start with 15 men and 15 women; have the men watch television for an hour while the women take a yoga class, record each participant’s blood pressure after the hour. Reverse, having the men take a yoga class while the women watch television.
Correct answer: B
Rationale: Option B is the most appropriate way to test the hypothesis that practicing yoga reduces blood pressure. By dividing 30 female participants into two groups with similar average blood pressure levels and testing each participant's blood pressure after participating in a yoga class, the researcher can effectively evaluate the impact of yoga on blood pressure. This design allows for a comparison between the two groups, helping to isolate the effects of yoga practice on blood pressure. Option A only involves one male and one female participant, which may not provide a representative sample. Option C introduces an additional variable of watching television, which could confound the results. Option D lacks consistency in the experimental design by switching the activities between men and women, making it difficult to attribute any observed changes solely to yoga practice.
2. 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.
3. In order, from lower to upper, the layers of the atmosphere are:
- A. Exosphere, thermosphere, mesosphere, stratosphere, troposphere
- B. Troposphere, stratosphere, mesosphere, thermosphere, exosphere
- C. Mesosphere, troposphere, stratosphere, thermosphere, exosphere
- D. Thermosphere, troposphere, stratosphere, mesosphere, exosphere
Correct answer: B
Rationale: The correct order of the layers of the atmosphere, from lower to upper, is troposphere, stratosphere, mesosphere, thermosphere, exosphere. The troposphere is the lowest layer where weather phenomena occur. The stratosphere contains the ozone layer, which absorbs and scatters the solar ultraviolet radiation. The mesosphere is where most meteorites burn up upon entering the Earth's atmosphere. The thermosphere is characterized by high temperatures due to the absorption of solar radiation. The exosphere is the outermost layer where the atmosphere transitions into space. Therefore, option B is the correct sequence, as it reflects the ascending order of the Earth's atmospheric layers.
4. What happens to glucose during glycolysis?
- A. Its energy is entirely lost.
- B. It splits into molecules of pyruvic acid.
- C. It is stored in NADH.
- D. It joins with molecules of citric acid.
Correct answer: B
Rationale: During glycolysis, glucose undergoes a series of enzymatic reactions in the cytoplasm of the cell, resulting in its breakdown into two molecules of pyruvic acid. This process also generates ATP and NADH as energy carriers. Choice A is incorrect because glucose is not entirely lost, but rather converted into other molecules. Choice C is incorrect because NADH is a product of glycolysis, not a storage form for glucose. Choice D is incorrect as glucose does not join with molecules of citric acid during glycolysis, but rather in subsequent stages of cellular respiration.
5. Three students measured the mass of a product of combustion. They recorded measurements of 14 g, 16 g, and 17 g. If the known mass of the product is 30 g, how would you describe the students’ measurements?
- A. Accurate
- B. Precise
- C. Both accurate and precise
- D. Neither accurate nor precise
Correct answer: B
Rationale: The students' measurements are precise because they are consistently close to each other. However, they are not accurate because all the measurements deviate from the known mass of the product (30 g). Accuracy refers to how close a measurement is to the true or accepted value, while precision refers to the level of agreement among repeated measurements. Since the students' measurements are consistent but do not align with the true value, they can be considered precise but not accurate. Choice A is incorrect because accuracy relates to the proximity of the measurements to the true value, which is not the case here. Choice C is incorrect because although the measurements are precise, they are not accurate. Choice D is incorrect because the measurements are precise as they show good agreement with each other, even though they are not accurate.
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