Nokea
Iodine is:
- A. used by the adenohypophysis to synthesize TSH.
- B. necessary for the synthesis of calcitonin by the thyroid gland.
- C. necessary for the synthesis of thyroid hormones.
- D. necessary for the synthesis of both PTH and calcitonin.
Correct Answer: C
Rationale: The correct answer is C because iodine is essential for the synthesis of thyroid hormones such as thyroxine (T4) and triiodothyronine (T3) in the thyroid gland. These hormones play a crucial role in regulating metabolism and growth. Choice A is incorrect because the adenohypophysis produces TSH, not iodine. Choice B is incorrect because calcitonin is produced by the parafollicular cells of the thyroid gland and does not require iodine for its synthesis. Choice D is incorrect because PTH (parathyroid hormone) is produced by the parathyroid glands and does not require iodine for its synthesis.
You may also like to solve these questions
Which statement about catalysts is correct?
- A. They decrease the time taken for a reaction to finish and they are unchanged at the end of the reaction.
- B. They decrease the time taken for a reaction to finish and they are used up in the reaction.
- C. They increase the time taken for a reaction to finish and they are unchanged at the end of the reaction.
- D. They increase the time taken for a reaction to finish and they are used up in the reaction.
Correct Answer: A
Rationale: The correct answer is A. Catalysts decrease the activation energy required for a reaction, speeding up the reaction without being consumed in the process. They provide an alternative pathway for the reaction to proceed, facilitating the reaction without being altered themselves. This is why they are unchanged at the end of the reaction. Choice B is incorrect because catalysts are not used up in the reaction. Choices C and D are also incorrect as catalysts do not increase the time taken for a reaction to finish nor are they consumed in the reaction.
The epiglottis?
- A. Closes trachea when swallowing
- B. Closes oesophagus during breathing
- C. Prevents the trachea from collapsing
- D. Closes the nasal cavity when swallowing
Correct Answer: A
Rationale: The correct answer is A: Closes trachea when swallowing. The epiglottis is a flap of tissue that covers the trachea (windpipe) during swallowing to prevent food or liquid from entering the airway. It ensures that food goes down the esophagus instead of the trachea. This action helps protect the respiratory system from aspiration. Choices B, C, and D are incorrect. B is incorrect because the epiglottis closes the trachea, not the esophagus, during swallowing. C is incorrect because the trachea is supported by rings of cartilage, not the epiglottis. D is incorrect because the epiglottis does not close the nasal cavity but rather the trachea.
Insufficient Levels of Thyroid Hormone in Adults Cause-------------
- A. Goiter
- B. Tetany
- C. Myxedema
- D. Cretinism
Correct Answer: C
Rationale: The correct answer is C: Myxedema. Insufficient levels of thyroid hormone in adults lead to myxedema due to decreased metabolism and energy production. Goiter (A) is the enlargement of the thyroid gland, not caused by low thyroid hormone levels. Tetany (B) is muscle spasms due to low calcium levels, not related to thyroid hormone deficiency. Cretinism (D) is a condition of severe hypothyroidism in infants, not in adults. Therefore, the correct choice is C as it directly relates to the consequences of low thyroid hormone levels in adults.
Acute attack of migraine can be treated by:
- A. Prazosin
- B. Ergotamine
- C. Propranolol
- D. Amphetamine
Correct Answer: B
Rationale: The correct answer is B: Ergotamine. Ergotamine is a vasoconstrictor that helps alleviate migraine symptoms by constricting blood vessels in the brain. It is commonly used to treat acute migraine attacks. Prazosin (A) is an alpha-blocker used for hypertension, not migraines. Propranolol (C) is a beta-blocker used for migraine prevention, not acute treatment. Amphetamine (D) is a stimulant used for ADHD, not migraine treatment. Ergotamine's vasoconstrictive properties make it effective for treating acute migraines.
Non-selective β-blockers are contraindicated in:
- A. Angina of effort
- B. Systemic hypertension
- C. Peripheral vascular disease
- D. Thyrotoxicosis
Correct Answer: C
Rationale: The correct answer is C: Peripheral vascular disease. Non-selective β-blockers can cause vasoconstriction and exacerbate peripheral vascular disease by reducing blood flow to the extremities. This can lead to worsening symptoms and potential tissue damage. Choices A, B, and D are incorrect because non-selective β-blockers are commonly used in angina of effort, systemic hypertension, and thyrotoxicosis, respectively, to decrease heart rate and blood pressure.