HESI A2 Biology Practice Test

Correct Answer: B

Rationale: Enzymes are typically proteins because they are biological catalysts made up of amino acids. Proteins have specific structures that allow them to bind to substrates and speed up chemical reactions. Fats, sugars, and neurons do not possess the specific structural properties required for enzyme function. Therefore, the correct answer is B (Proteins).

Correct Answer: B

Rationale: Enzymes are typically proteins because they are biological catalysts made up of amino acids. Proteins have specific structures that allow them to bind to substrates and speed up chemical reactions. Fats, sugars, and neurons do not possess the specific structural properties required for enzyme function. Therefore, the correct answer is B (Proteins).

Correct Answer: C

Rationale: The correct answer is C because plant cells have a rigid cell wall that prevents them from forming a contractile ring during cell division. The cell wall provides structural support, making it challenging for plant cells to constrict and pinch apart like animal cells. This rigidity limits the flexibility needed for the contractile ring to form and function effectively. Plant cells primarily rely on other mechanisms such as cell plate formation for division. Choices A and B are incorrect as they do not address the specific structural difference between plant and animal cells. Choice D is incorrect as it does not provide any relevant information on the topic.

Correct Answer: D

Rationale: The correct answer is D: Biomes. Biomes are large geographical areas characterized by specific climate, vegetation, and animal life. Tundra, savannas, grasslands, deserts, and rainforests are all examples of biomes. They are classified based on factors like temperature, precipitation, and flora/fauna. Biomasses (A) refer to the total mass of living organisms in a given area. Biospheres (B) are the regions of the Earth where life exists. Biodiversity (C) refers to the variety and variability of life forms in a specific habitat, not the specific types of habitats themselves.

Correct Answer: D

Rationale: The correct answer is D because it follows the structure of a hypothesis: it states a relationship between two variables (exposure to red light and plant growth) that can be tested. It is specific, testable, and predicts an outcome. Choice A is a general statement, not a testable hypothesis. Choice B is subjective and not testable. Choice C lacks specificity and does not clearly define the relationship being tested.