Which hormone is responsible for regulating blood sugar levels?

Correct Answer: B

Rationale: The correct answer is B: Insulin. Insulin, produced by the pancreas, plays a crucial role in regulating blood sugar levels by facilitating glucose uptake into cells. Thyroxine, adrenaline, and cortisol do not directly regulate blood sugar levels. Thyroxine is produced by the thyroid gland and regulates metabolism. Adrenaline and cortisol are hormones involved in stress responses and do not have a primary function in blood sugar regulation. Understanding the functions of these hormones is crucial in differentiating their roles in the body and identifying the specific hormone responsible for blood sugar regulation.

Correct Answer: B

Rationale: The correct answer is B: Alveoli. The alveoli in the lungs are responsible for gas exchange. They have a thin membrane that allows for the exchange of oxygen and carbon dioxide between the air in the lungs and the blood in the capillaries surrounding them. This process is essential for respiration, providing oxygen to the body's tissues and removing carbon dioxide, a waste product of cellular metabolism. Choices A, C, and D are incorrect. The trachea is a passageway that carries air to and from the lungs but is not directly involved in gas exchange. Bronchi are airway passages that further divide into smaller bronchioles leading to the alveoli but do not perform gas exchange themselves. The diaphragm is a muscle involved in the breathing process by aiding in inhalation and exhalation, but it is not the structure responsible for gas exchange in the respiratory system.

Correct Answer: B

Rationale: Thyroxine, also known as T4, is the hormone produced by the thyroid gland to regulate metabolism. It is essential for controlling the body's metabolic rate, heart and digestive function, muscle control, brain development, and bone maintenance. Adrenaline is produced by the adrenal glands, not the thyroid gland. Cortisol is produced by the adrenal cortex, not the thyroid gland. Insulin is produced by the pancreas, not the thyroid gland. Therefore, the correct answer is Thyroxine (B).

Correct Answer: B

Rationale: The correct answer is B: 'To clot blood.' Platelets play a crucial role in the clotting process, forming a plug at the site of blood vessel injury to prevent excessive bleeding. While red blood cells carry oxygen, white blood cells fight infection, and nutrients are transported by plasma, platelets are specifically responsible for blood clotting. Choice A is incorrect because red blood cells are responsible for carrying oxygen. Choice C is incorrect because white blood cells are primarily involved in fighting infection. Choice D is incorrect as the transport of nutrients is mainly carried out by plasma, not platelets.

Correct Answer: B

Rationale: The correct answer is B: Kidneys. The kidneys are responsible for filtering waste from the blood and maintaining electrolyte balance. They help regulate the body's fluid levels and produce urine as a means of waste elimination. The liver primarily plays a role in detoxification and metabolism, not in maintaining electrolyte balance or filtering waste from the blood. The heart is responsible for pumping blood, not for electrolyte balance or waste filtration. The lungs are primarily involved in gas exchange, not in maintaining electrolyte balance or filtering waste from the blood.