Nokea
Which artery generally gives rise to inferior thyroid artery?
- A. External carotid artery
- B. Internal carotid artery
- C. Brachiocephalic trunk
- D. Thyrocervical trunk
Correct Answer: D
Rationale: Step-by-step rationale:
1. The inferior thyroid artery typically arises from the thyrocervical trunk.
2. The thyrocervical trunk is a branch of the subclavian artery.
3. This artery supplies blood to the thyroid gland.
4. The external carotid artery and internal carotid artery do not give rise to the inferior thyroid artery.
5. The brachiocephalic trunk does not directly supply blood to the thyroid gland.
In conclusion, the correct answer is D because the thyrocervical trunk is the main artery that gives rise to the inferior thyroid artery, providing blood supply to the thyroid gland.
You may also like to solve these questions
The liberation of proteins to free amino acids (final digestive step) occur in all of the following EXCEPT:
- A. enterocyte cytoplasm
- B. brush border
- C. small intestine lumen
- D. stomach
Correct Answer: D
Rationale: The correct answer is D: stomach. Proteins are broken down into amino acids through the process of digestion. In the stomach, proteins are broken down into smaller peptides, not free amino acids. The final step of liberating proteins into free amino acids occurs in the enterocyte cytoplasm, where absorbed nutrients are further processed. The brush border of the small intestine is where the final stages of digestion take place before absorption. The small intestine lumen is the space where digestion occurs, but the actual liberation of proteins into free amino acids happens in the enterocyte cytoplasm.
Monoamine oxidase enzyme (MAO) is responsible for:
- A. Adrenaline activation
- B. Adrenaline synthesis
- C. Adrenaline degradation
- D. Acetylcholine degradation
Correct Answer: C
Rationale: Monoamine oxidase enzyme (MAO) is responsible for the degradation of neurotransmitters like adrenaline. MAO breaks down adrenaline into inactive metabolites, regulating its levels in the body. This process is crucial for maintaining neurotransmitter balance. Choice A is incorrect because MAO does not activate adrenaline. Choice B is incorrect as MAO is not involved in adrenaline synthesis. Choice D is incorrect as MAO does not degrade acetylcholine, but rather neurotransmitters like serotonin, dopamine, and adrenaline.
A drug useful in the treatment of acute attack of migraine is:
- A. Sumatriptan
- B. Ergometrine
- C. Dihydroergometrine
- D. Propranolol
Correct Answer: A
Rationale: Sumatriptan is the correct answer for treating acute migraine attacks as it is a specific serotonin receptor agonist that helps constrict blood vessels in the brain. Ergometrine and dihydroergometrine are ergot alkaloids used for other conditions, not migraine. Propranolol is a beta-blocker used for migraine prevention, not acute attacks.
Which of the following explains the suppression of lactation during pregnancy?
- A. Blood prolactin levels are too low for milk production to occur
- B. Human placental lactogen levels are too low for milk production to occur
- C. The fetal adrenal gland does not produce sufficient estriol
- D. Blood levels of estrogen and progesterone are high
Correct Answer: D
Rationale: The correct answer is D. During pregnancy, high levels of estrogen and progesterone inhibit lactation by suppressing the release of prolactin, the hormone responsible for milk production. Estrogen and progesterone maintain the pregnancy and prevent premature labor, so the body prioritizes their functions over lactation. Choices A, B, and C are incorrect because low blood prolactin levels, human placental lactogen levels, and fetal adrenal gland's estriol production are not directly related to the suppression of lactation during pregnancy.
One of the two hormones made by the pituitary that help regulate reproductive cells is luteinizing hormone. The other hormone is .
- A. follicle-stimulating hormone
- B. epinephrine
- C. norepinephrine
- D. androgens
Correct Answer: A
Rationale: The correct answer is A: follicle-stimulating hormone (FSH). FSH is the other hormone made by the pituitary gland that helps regulate reproductive cells, along with luteinizing hormone (LH). FSH is responsible for stimulating the growth and maturation of ovarian follicles in females and spermatogenesis in males.
Explanation:
1. FSH is directly involved in the reproductive process by stimulating follicle development and sperm production.
2. Epinephrine and norepinephrine are not hormones produced by the pituitary gland and are involved in the stress response.
3. Androgens are male sex hormones produced primarily by the testes, not the pituitary gland.
In summary, FSH is the correct answer as it plays a crucial role in regulating reproductive cells, while the other choices are not involved in the reproductive system or are not produced by the pituitary gland.