TEAS Practice Test Science

Correct Answer: B

Rationale: The correct answer is B: Cerebellum. The cerebellum is responsible for coordinating muscle movements by receiving information from the sensory systems, spinal cord, and other parts of the brain to regulate motor movements. It plays a crucial role in maintaining balance, posture, and smooth coordination of voluntary movements. The other choices are incorrect because: A: The cerebrum is primarily involved in higher brain functions such as thinking, decision-making, and emotions. C: The thalamus acts as a relay station for sensory information but does not directly control muscle coordination. D: The medulla oblongata is responsible for regulating vital functions such as breathing, heart rate, and blood pressure, but not specifically muscle coordination.

Correct Answer: A

Rationale: The independent variable is what the researcher manipulates to observe its effect on the dependent variable. In this study, the botanist is testing if temperature affects root growth. Therefore, the independent variable is temperature (choice A). The botanist will change the temperature levels to see how it influences root growth. Choices B, C, and D are not the independent variable as the botanist is not directly manipulating seedlings, light, or root length to study the effect on root growth.

Correct Answer: B

Rationale: The correct answer is B: To transport oxygen and nutrients. The circulatory system, composed of the heart, blood vessels, and blood, primarily functions to deliver oxygen and nutrients to the body's cells and remove waste products. The heart pumps oxygen-rich blood to tissues and organs, ensuring they receive the necessary nutrients for energy production. In contrast, choices A, C, and D are incorrect. Regulating body temperature is primarily the role of the body's thermoregulatory system, fighting infection is the function of the immune system, and breaking down waste is the responsibility of the digestive system.

Correct Answer: B

Rationale: The correct answer is B: Parathyroid hormone. PTH is produced by the parathyroid glands and plays a crucial role in regulating calcium levels in the blood. It increases calcium levels by stimulating the release of calcium from bones, enhancing calcium absorption in the intestines, and reducing calcium excretion in the kidneys. Insulin (A) regulates blood sugar levels, not calcium. Thyroid hormone (C) controls metabolism, not calcium levels. Glucagon (D) increases blood sugar levels, not calcium.

Correct Answer: A

Rationale: The correct answer is A: Left atrium. The left atrium receives oxygenated blood from the lungs via the pulmonary veins. This oxygenated blood is then pumped into the left ventricle and circulated to the rest of the body. The right atrium receives deoxygenated blood from the body via the vena cava. Choices B, C, and D are incorrect because the right atrium receives deoxygenated blood from the body, the left ventricle pumps oxygenated blood to the body, and the right ventricle pumps deoxygenated blood to the lungs for oxygenation, respectively.