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: B

Rationale: Proteins are the best choice to increase muscle mass and strength because they are essential for muscle repair and growth. Proteins are made up of amino acids, which are the building blocks of muscles. Consuming enough protein provides the body with the necessary nutrients to repair and build muscle tissue. Carbohydrates are primarily for energy, lipids are for long-term energy storage, and nucleic acids are not directly involved in muscle growth. Therefore, proteins are the most suitable option for athletes looking to increase muscle mass and strength.

Correct Answer: B

Rationale: The correct answer is B: Smooth, skeletal, cardiac. Smooth muscle tissue is found in organs and blood vessels, skeletal muscle tissue is attached to bones for movement, and cardiac muscle tissue is found in the heart. The other choices are incorrect because they do not accurately represent the types of muscle tissue in the human body. Choice A includes organs and structures that are not muscle tissues. Choice C lists a neuron (nerve cell), epithelial (covering and lining tissue), and collagen (connective tissue), which are not types of muscle tissue. Choice D is incorrect as it does not provide the correct types of muscle tissue.

Correct Answer: A

Rationale: The correct answer is A: electron transport chain. This step in cellular respiration produces the greatest amount of ATP through oxidative phosphorylation, where electrons are passed through a series of protein complexes to generate a proton gradient used to produce ATP. In contrast, glycolysis only produces a small amount of ATP, the citric acid cycle produces some ATP but not as much as the electron transport chain, and fermentation doesn't produce ATP through oxidative phosphorylation. Therefore, the electron transport chain is the most efficient step in ATP production during cellular respiration.

Correct Answer: A

Rationale: The correct answer is A: Atmosphere. The atmosphere is the layer of gases that surrounds a planet. It consists of different layers, including the stratosphere and troposphere mentioned in the other choices. The biosphere refers to the regions on Earth where living organisms exist, not the gases surrounding the planet. Therefore, the correct term for the mixture of gases surrounding a planet is the atmosphere.