Biology HESI A2 Practice Test

Correct Answer: A

Rationale: The correct answer is A: hypothesis. A hypothesis is a statement that proposes an explanation for a phenomenon based on available evidence. It helps guide scientific inquiry by providing a testable prediction. Observations (B) are simply data collected through senses. Experiments (C) involve testing hypotheses through controlled conditions. Conclusions (D) are interpretations drawn from the data collected. Therefore, a hypothesis is the initial statement or explanation of certain events or happenings in the scientific process.

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: 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: B

Rationale: The correct answer is B: Tendons, ligaments. Tendons connect muscles to bones, enabling movement. Ligaments connect bones to each other, providing stability. Muscles and ligaments are not directly involved in connecting muscles to bones. Therefore, option B is the most appropriate choice.

Correct Answer: C

Rationale: The correct answer is C: Uracil. DNA bases consist of Adenine, Thymine, Cytosine, and Guanine, whereas Uracil is only found in RNA. DNA uses Thymine, while RNA uses Uracil as one of its bases. Therefore, Uracil is not a part of DNA bases. Adenine, Thymine, and Cytosine are all essential components of DNA.