Sperm production begins in the

Correct Answer: A

Rationale: The correct answer is A: seminiferous tubules. Sperm production begins in the seminiferous tubules of the testes through a process called spermatogenesis. This is where immature germ cells called spermatogonia undergo multiple divisions to eventually form mature sperm cells. The other choices, B: epididymis, C: vas deferens, and D: ejaculatory duct, are incorrect as they are not sites of sperm production but rather play roles in sperm maturation, storage, and transportation during ejaculation.

Correct Answer: B

Rationale: The correct answer is B: cervix. The cervix is the structure between the uterus and the vagina. It functions as a passageway for sperm to travel to the uterus and for menstrual blood to flow out of the uterus. The other choices are incorrect because: A: Uterine tube (fallopian tube) connects the ovary to the uterus, not between the uterus and vagina. C: Vulva refers to the external genitalia, not the internal structure between the uterus and vagina. D: Hymen is a thin membrane at the vaginal opening, not the structure between the uterus and vagina.

Correct Answer: B

Rationale: The correct answer is B: Hypoglycemia. Phenytoin is an anticonvulsant medication that commonly causes side effects such as ataxia, hirsutism, and gum hypertrophy. However, hypoglycemia is not a known side effect of phenytoin. It is important to monitor blood sugar levels in patients taking anticonvulsants, as some medications may lead to hyperglycemia rather than hypoglycemia. Therefore, choice B is the correct answer. Choices A, C, and D are incorrect as they are common side effects associated with phenytoin use.

Correct Answer: D

Rationale: The correct answer is D: On-Off phenomenon. Levodopa is a medication used to treat Parkinson's disease by increasing dopamine levels in the brain. The On-Off phenomenon refers to the fluctuation between periods of good symptom control (On) and poor symptom control (Off) experienced by some patients taking levodopa. Tremor (choice A) is a symptom of Parkinson's but not directly caused by levodopa. Spasticity (choice B) is not typically associated with levodopa use. Akinesia (choice C) is a symptom of Parkinson's but not a direct effect of levodopa. Therefore, the correct answer is D due to levodopa's potential to cause the On-Off phenomenon in Parkinson's disease treatment.

Correct Answer: C

Rationale: The correct answer is C: Diarrhoea. Morphine is known to cause constipation, not diarrhoea. Morphine binds to opioid receptors in the gut, reducing peristalsis and causing constipation. Analgesia and sedation are known effects of morphine due to its action on the central nervous system. Morphine is also known to increase prolactin secretion by acting on the hypothalamus. Therefore, the correct answer is C, as morphine does not typically cause diarrhoea.