Practice Science TEAS Test

Correct Answer: B

Rationale: The correct answer is B: To filter blood and produce urine. The kidneys play a crucial role in filtering waste products and excess substances from the blood to form urine, which helps maintain the body's balance of fluids and electrolytes. This process is essential for regulating blood pressure, producing hormones, and maintaining overall bodily function. Choices A, C, and D are incorrect because the kidneys are not involved in digesting food, absorbing nutrients, or transporting oxygen.

Correct Answer: B

Rationale: The correct answer is B: Melatonin. Melatonin is a hormone produced by the pineal gland that plays a key role in regulating the sleep-wake cycle. It helps control the body's internal clock and signals when it's time to sleep. Cortisol (choice A) is a stress hormone, thyroxine (choice C) regulates metabolism, and insulin (choice D) controls blood sugar levels, but they do not directly regulate the sleep-wake cycle. Melatonin is the only hormone among the choices specifically associated with sleep regulation.

Correct Answer: C

Rationale: The correct answer is C: Spleen. The spleen filters pathogens from the blood through its white pulp, which contains immune cells that detect and destroy harmful microorganisms. The spleen also removes old or damaged red blood cells. A: Lymph nodes filter lymph, not blood. B: Kidneys filter waste from the blood but not pathogens. D: Pancreas is primarily involved in digestion and hormone regulation, not blood filtration.

Correct Answer: B

Rationale: The correct order of the layers of the epidermis from most superficial to deepest is: S. corneum, S. lucidum, S. granulosum, S. spinosum, S. basale (Choice B). This is because the outermost layer is the stratum corneum, followed by the stratum lucidum, then the stratum granulosum, stratum spinosum, and finally the stratum basale which is the deepest layer where new skin cells are produced. Choices A, C, and D do not follow this correct progression and therefore are incorrect.

Correct Answer: B

Rationale: The correct answer is B: Hypothalamus. The hypothalamus regulates body temperature, hunger, and thirst through its control of the autonomic nervous system and hormonal systems. It plays a crucial role in maintaining homeostasis. The cerebellum (A) is responsible for coordination and balance, the thalamus (C) acts as a relay station for sensory information, and the medulla oblongata (D) regulates vital functions such as breathing and heart rate, but not body temperature, hunger, or thirst.