HESI A2 Biology Practice Test

Correct Answer: B

Rationale: To focus an image using a compound microscope, adjusting the fine adjustment is correct as it allows for precise focusing when switching magnifications. Coarse adjustment is only used initially to bring the specimen into view, while the stage adjustment is used to center the specimen. Therefore, B is correct as it ensures clear and sharp image focus without unnecessary readjustments. Choices A and C are incorrect as they do not address the specific need for precise focusing when changing magnifications, leading to potential blurriness or loss of focus in the image.

Correct Answer: C

Rationale: Anaerobic respiration occurs in bacteria because they live in environments with low oxygen levels. Bacteria adapt to anaerobic conditions by utilizing alternative pathways to generate energy without oxygen. This process allows them to survive and thrive in oxygen-deprived environments. The other choices are incorrect because animals require oxygen for aerobic respiration, plants use sunlight for photosynthesis, and option D is incorrect as bacteria indeed undergo anaerobic respiration in low oxygen environments.

Correct Answer: B

Rationale: The correct answer is B because animal cells do not use chloroplasts to gain energy, they use mitochondria for cellular respiration. Lysosomes in animal cells break down old cells (A) and plant cells have a cell wall (C). Choice D is incorrect as B is false.

Correct Answer: B

Rationale: The correct answer is B because of osmosis. Saltwater has a higher concentration of solute than the egg, causing water to move out of the egg, leading to shrinkage. A is incorrect as the egg will lose water, not expand. C is incorrect as there will be a change due to osmosis. D is incorrect as an effect will occur.

Correct Answer: D

Rationale: The correct answer is D because all the statements mentioned in choices A, B, and C are true. A: The respiratory system consists of all organs involved in breathing, including the nose, pharynx, larynx, trachea, bronchi, and lungs. B: Organs included in the respiratory system are the nose, pharynx, larynx, trachea, bronchi, and lungs. C: The respiratory system conveys oxygen into our bodies and removes carbon dioxide from our bodies. Therefore, as all three statements are true, the correct answer is D - All of the Above. The other choices are incorrect because they do not encompass all the organs involved in the respiratory system or the functions it performs.