Biology HESI A2 Practice Test

Correct Answer: D

Rationale: Homeostasis is necessary to maintain stable internal conditions in the body for optimal function. A: Temperature regulation ensures enzymes work efficiently. B: pH balance is crucial for enzyme activity and cell function. C: Glucose levels impact energy production. D: All choices are essential for overall health and function, making D the correct answer. Maintaining just one aspect wouldn't be enough to support the body's complex processes.

Correct Answer: A

Rationale: The correct answer is A: The Coriolis effect. The Earth's rotation causes the Coriolis effect, which influences the direction of moving objects on the Earth's surface, including the atmosphere. This effect is responsible for the rotation of winds in the atmosphere and the movement of ocean currents. The Coriolis effect deflects moving objects to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. Summary of why the other choices are incorrect: B: The Corona effect is not related to the Earth's rotation but rather refers to the outermost layers of the sun's atmosphere. C: The Archimedes effect is related to buoyancy and the upward force exerted on an object submerged in a fluid, not the Earth's rotation. D: The tidal effect is caused by the gravitational pull of the moon and the sun on Earth's oceans, not directly related to the Earth's rotation impacting the atmosphere and objects on the surface.

Correct Answer: C

Rationale: The correct answer is C because both prokaryotic and eukaryotic cells possess a cell membrane. The cell membrane is a crucial structure present in all cells that separates the internal cellular environment from the external environment. In prokaryotic cells, the cell membrane is the outermost boundary, while in eukaryotic cells, it is surrounded by other membrane-bound organelles. Choice A is incorrect because prokaryotic cells lack membrane-bound organelles, but they still have a cell membrane. Choice B is incorrect because eukaryotic cells do possess a cell membrane. Choice D is incorrect as it contradicts the basic understanding of cell biology.

Correct Answer: B

Rationale: The correct answer is B: Actual physical appearance. Phenotype refers to the observable characteristics of an individual, such as physical traits, behavior, and physiological properties. It is the result of the interaction between an individual's genetic makeup (genotype) and environmental factors. Choice A, genetic makeup, refers to genotype. Choice C, recessive alleles, specifically describes a type of gene variant and is not the definition of phenotype. Choice D, None of the above, is incorrect as the phenotype does refer to the actual physical appearance and observable traits of an individual.

Correct Answer: C

Rationale: The correct answer is C because molecules move from areas of high concentration to low concentration through a process called passive diffusion, which does not require energy. This movement occurs to reach equilibrium. Choice A is incorrect as some molecules can pass through cell membranes using channels or transporters. Choice B is incorrect because molecules move from high to low concentration in passive transport. Choice D is incorrect because molecules are constantly moving due to various forces.