HESI A2 Anatomy and Physiology Quizlet

Correct Answer: B

Rationale: The correct answer is B: To fight infection. White blood cells are part of the immune system and play a crucial role in defending the body against infections by attacking and destroying pathogens such as bacteria, viruses, and other foreign invaders. They are key players in the immune response. A: White blood cells do not carry oxygen to the cells. That is the role of red blood cells. C: White blood cells do not transport nutrients. Nutrients are transported by the bloodstream and absorbed by various organs. D: White blood cells are not responsible for clotting blood. Platelets are primarily responsible for blood clotting.

Correct Answer: B

Rationale: The correct answer is B: Pituitary gland. The pituitary gland is known as the 'master gland' because it controls the functions of other endocrine glands in the body. It secretes hormones that regulate various bodily functions, such as growth, metabolism, and reproduction. Other choices are incorrect because the thyroid gland mainly regulates metabolism, the adrenal gland is responsible for stress response and metabolism, and the pineal gland produces melatonin to regulate sleep-wake cycles. The pituitary gland stands out as the 'master gland' due to its control over other gland functions.

Correct Answer: B

Rationale: The correct answer is B: Adrenaline. The adrenal medulla is part of the adrenal glands and is responsible for producing adrenaline, also known as epinephrine. Adrenaline is a hormone that plays a crucial role in the body's fight or flight response, increasing heart rate, blood flow to muscles, and overall alertness in response to stress or danger. Insulin (A) is produced by the pancreas to regulate blood sugar levels, cortisol (C) is produced by the adrenal cortex to regulate stress response and metabolism, and melatonin (D) is produced by the pineal gland to regulate sleep-wake cycles.

Correct Answer: A

Rationale: The correct answer is A: Epithelial tissue. Epithelial tissue is characterized by cells tightly packed together, lining body surfaces or cavities. In this case, the cells are found on the internal surface of the stomach, which aligns with the location of epithelial tissue in the body. The absence of extracellular matrix, tall and thin cells, and lack of blood vessels all point towards epithelial tissue, which functions in protection, absorption, and secretion. Summary: B: Connective tissue would have extracellular matrix and blood vessels. C: Muscle tissue would have muscle fibers and blood vessels. D: Cartilage tissue would have a gel-like matrix and chondrocytes.

Correct Answer: B

Rationale: The correct answer is B: Mitochondria. Mitochondria are known as the powerhouse of the cell because they are responsible for energy production through the process of cellular respiration. They produce ATP, the main energy currency of the cell. The other choices are incorrect because the nucleus is responsible for storing genetic material, ribosomes are involved in protein synthesis, and the Golgi apparatus is responsible for packaging and transporting proteins. Therefore, only the mitochondria play a direct role in energy production within the cell.