ati teas 7 science

Correct Answer: B

Rationale: The gravitational potential energy of an object is determined by its position relative to the ground. The higher the object is from the ground, the greater its gravitational potential energy. This is because the gravitational potential energy is directly proportional to the distance from the ground. Therefore, choice B, the distance from the ground, affects the gravitational potential energy of an object the most. Incorrect choices: A: The mass of the object does affect the gravitational potential energy, but it is not the most significant factor. C: The gravitational force affects the weight of an object but does not directly determine its gravitational potential energy. D: The shape of the object does not affect its gravitational potential energy; only the distance from the ground matters.

Correct Answer: C

Rationale: The correct answer is C: Polypeptide. Translation is the process in which mRNA is decoded by ribosomes to synthesize a specific polypeptide. During translation, transfer RNA (tRNA) molecules bring specific amino acids to the ribosome based on the mRNA codons, and these amino acids are joined together to form a polypeptide chain. The other choices are incorrect because translation does not result in the production of DNA (A), lipids (B), or carbohydrates (D). Translation specifically involves the synthesis of polypeptides, making choice C the correct answer.

Correct Answer: C

Rationale: The correct answer is C: Control sleep-wake cycles. Melatonin is primarily responsible for regulating our sleep-wake cycles, also known as the circadian rhythm. This hormone is released by the pineal gland in response to darkness, signaling to the body that it is time to sleep. Melatonin helps to synchronize our internal body clock with the natural day-night cycle. Choice A (Regulate blood pressure) is incorrect because melatonin does not play a direct role in regulating blood pressure. Choice B (Stimulate the digestive system) is incorrect as melatonin is not involved in stimulating the digestive system. Choice D (Maintain bone density) is also incorrect as melatonin's primary function is not related to bone density regulation.

Correct Answer: B

Rationale: The correct answer is B: Liver. The liver is responsible for detoxifying chemicals and metabolizing drugs due to its enzymes that break down substances. It also helps in excreting waste products. The kidneys (A) filter blood and regulate fluid balance. The heart (C) pumps blood throughout the body. The pancreas (D) produces digestive enzymes and insulin. Thus, the liver is the primary organ involved in detoxification and drug metabolism.

Correct Answer: B

Rationale: The correct answer is B: Myosin. Myosin is the protein complex responsible for the thick filament in the sarcomere. It forms cross-bridges with actin during muscle contraction. Actin (choice A) is the thin filament in the sarcomere. Tropomyosin (choice C) is a regulatory protein that covers the myosin-binding sites on actin when the muscle is at rest. Troponin (choice D) is another regulatory protein that helps regulate muscle contraction by binding calcium ions.