To which two systems does the urethra belong?

Correct Answer: B

Rationale: The urethra belongs to both the urinary and reproductive systems. In the urinary system, it functions as a passage for urine from the bladder to exit the body. In the reproductive system, it serves as a conduit for the expulsion of semen during ejaculation. Choice A is incorrect because the urethra is not part of the endocrine system. Choice C is also incorrect because the urethra is not primarily associated with the endocrine system. Choice D is incorrect as the urethra is not part of the digestive or cardiovascular systems.

Correct Answer: C

Rationale: The gall bladder is part of the digestive system. Its primary function is to store and concentrate bile produced by the liver and release it into the small intestine to aid in the digestion of fats. This process facilitates the breakdown and absorption of fats from the food we consume. Choices A, B, and D are incorrect as the gall bladder is not associated with the endocrine, urinary, or nervous systems.

Correct Answer: D

Rationale: The correct answer is D, 'Production of antibodies.' Antibodies are generated as part of the specific immune response, which targets specific antigens. Nonspecific immune responses, such as inflammation, vasodilation, and histamine release, are general defense mechanisms aimed at combating various pathogens. Inflammation is a localized response to infection or injury, vasodilation increases blood flow to the affected area, and histamine release triggers inflammatory responses. It's vital to differentiate between nonspecific responses that provide immediate, general protection and specific responses designed to tackle particular threats.

Correct Answer: B

Rationale: The urinary system, specifically the kidneys, is primarily responsible for regulating electrolytes in the body by filtering and excreting excess electrolytes, such as sodium, potassium, and chloride, through urine. The kidneys play a crucial role in maintaining the body's electrolyte balance, which is essential for various bodily functions and overall health. The endocrine system regulates hormones, the lymphatic system is involved in immunity, and the nervous system controls communication in the body. Therefore, the correct answer is B, the urinary system, as it directly handles electrolyte regulation by adjusting their excretion levels.

Correct Answer: D

Rationale: The correct answer is D: 'It supplies blood to the heart muscle.' The coronary artery's main function is to supply oxygenated blood to the heart muscle, ensuring that the heart receives the necessary nutrients and oxygen it needs to function properly. Choices A, B, and C are incorrect because the coronary artery specifically delivers oxygenated blood to the heart muscle, not deoxygenated blood to the lungs or blood to the rest of the body.