HESI A2
HESI A2 Biology Practice Test 2024
1. What is the main component of blood plasma?
- A. Proteins
- B. Water
- C. Red Blood Cells
- D. Platelets
Correct answer: B
Rationale: The correct answer is B: Water. Blood plasma is composed mostly of water, which acts as a solvent for various nutrients and substances. Choices A, C, and D are incorrect. Proteins are indeed present in blood plasma but are not the main component. Red blood cells and platelets are cellular components of blood, not the main component of blood plasma.
2. Why is homeostasis necessary?
- A. It maintains temperature
- B. It maintains pH
- C. It maintains glucose levels
- D. All of the above
Correct answer: D
Rationale: Homeostasis is necessary because it ensures the maintenance of a stable, relatively constant internal environment. This includes regulating various factors such as temperature, pH levels, and glucose levels to support optimal bodily functions and overall health. Choices A, B, and C are all correct as they represent key aspects of homeostasis that contribute to maintaining the body's internal balance.
3. Tundra, savannas, grasslands, deserts, and rainforests are examples of what?
- A. Biomasses
- B. Biospheres
- C. Biodiversity
- D. Biomes
Correct answer: D
Rationale: Tundra, savannas, grasslands, deserts, and rainforests are examples of biomes. A biome is a large geographical area with similar climatic conditions and distinct flora and fauna. Each biome has its unique characteristics, such as temperature, precipitation levels, and types of vegetation, which define the ecosystem within that region. Biomasses refer to the total mass of living organisms in a given area, biospheres are the global ecological system integrating all living beings and their relationships, and biodiversity represents the variety of life forms in a specific habitat.
4. What is another name for the light-independent reaction in plants?
- A. Photosynthesis
- B. Calvin cycle
- C. Germination
- D. Phosphorus cycle
Correct answer: B
Rationale: The light-independent reaction in plants is also known as the Calvin cycle. This biochemical pathway, named after Melvin Calvin who discovered it, takes place in the stroma of chloroplasts and is responsible for converting carbon dioxide into glucose using ATP and NADPH generated during the light-dependent reactions of photosynthesis. The Calvin cycle does not directly require light to function, hence the alternative name as the light-independent reaction. Choices A, C, and D are incorrect. Photosynthesis is the overall process of converting light energy into chemical energy, which includes both light-dependent and light-independent reactions. Germination is the process where a seed sprouts into a new plant. The phosphorus cycle is the biogeochemical cycle that describes the movement of phosphorus through the lithosphere, hydrosphere, and biosphere.
5. Which of the following is not true about enzymes?
- A. They catalyze reactions
- B. They lower the activation energy needed
- C. They have an active site
- D. They are typically proteins
Correct answer: B
Rationale: Enzymes lower the activation energy needed for a reaction to occur, not raise it. By lowering the activation energy, enzymes facilitate reactions, making them occur more easily and rapidly. Choice A is correct as enzymes indeed catalyze reactions. Choice C is correct as enzymes have specific active sites where substrates bind. Choice D is correct as enzymes are commonly proteins, although some RNA molecules also exhibit catalytic properties.
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