Nokea
Adrenaline can produce all of the following effects EXCEPT:
- A. Relaxation of bronchial muscle
- B. Increases cardiac contractility
- C. Increases intestinal motility
- D. Increases sweat secretion
Correct Answer: C
Rationale: Adrenaline, also known as epinephrine, is a hormone that activates the fight-or-flight response. It causes bronchial muscle relaxation (A), increases cardiac contractility (B), and increases sweat secretion (D) to prepare the body for action. However, adrenaline inhibits intestinal motility (C) to conserve energy for vital functions during stressful situations. Therefore, the correct answer is C because adrenaline does not increase intestinal motility. Relaxation of bronchial muscle, increased cardiac contractility, and increased sweat secretion are all effects of adrenaline, making choices A, B, and D incorrect, respectively.
You may also like to solve these questions
A girl presents with delayed puberty, absent secondary sexual characteristics, and primary amenorrhea. She also appears to be hypertensive and hypokalemia. Which of the following enzymes is increased if there is virilization of a person?
- A. 11b-Hydroxylase
- B. 17a-Hydroxylase
- C. 21b-Hydroxylase
- D. Pyruvate Kinase
Correct Answer: A
Rationale: The correct answer is A: 11b-Hydroxylase. In cases of virilization, increased androgen production occurs. 11b-Hydroxylase is involved in the synthesis of cortisol and aldosterone. When there is a deficiency in this enzyme, excess androgens are diverted towards the production of testosterone, leading to virilization. In contrast, choices B (17a-Hydroxylase) and C (21b-Hydroxylase) deficiencies result in decreased androgen production. Choice D, Pyruvate Kinase, is not related to steroid hormone synthesis. Therefore, the correct enzyme in this scenario is 11b-Hydroxylase.
Sometimes prolonged excessive exposure to high hormone concentrations causes a phenomenon known as ________.
- A. diabetes mellitus
- B. cellular inhibition
- C. down-regulation
- D. metabolism of protein kinases
Correct Answer: C
Rationale: The correct answer is C: down-regulation. Prolonged exposure to high hormone concentrations can lead to down-regulation, where cells decrease their responsiveness to the hormone by reducing the number of hormone receptors. This is a regulatory mechanism to prevent overstimulation.
A: Diabetes mellitus is a chronic condition characterized by high blood sugar levels, usually caused by insulin deficiency or insulin resistance, not directly related to prolonged exposure to high hormone concentrations.
B: Cellular inhibition is a broad term that may refer to various cellular processes being inhibited, but it is not a specific phenomenon resulting from prolonged exposure to high hormone concentrations.
D: Metabolism of protein kinases is a cellular process involved in signal transduction, but it is not a direct consequence of prolonged exposure to high hormone concentrations.
The transcription of new messenger RNA is a function of __________.
- A. pancreatic hormones
- B. steroid hormones
- C. catecholamines
- D. pituitary gland hormones
Correct Answer: B
Rationale: The correct answer is B: steroid hormones. Steroid hormones are known to regulate gene expression by binding to specific receptors and influencing transcription processes. They can directly affect the transcription of new messenger RNA in the cell. Pancreatic hormones (A), catecholamines (C), and pituitary gland hormones (D) are not directly involved in the transcription of new messenger RNA. Pancreatic hormones primarily regulate blood sugar levels, catecholamines are involved in the fight-or-flight response, and pituitary gland hormones regulate various functions such as growth, reproduction, and metabolism.
The largest endocrine gland(s) that makes 3 hormones that affect the metabolism is the:
- A. pancreas
- B. adrenal glands
- C. thyroid gland
- D. pituitary gland
Correct Answer: C
Rationale: The correct answer is C: thyroid gland. The thyroid gland is the largest endocrine gland that produces 3 hormones (T3, T4, and calcitonin) that regulate metabolism. T3 and T4 control the body's metabolic rate, while calcitonin helps regulate calcium levels in the blood. The pancreas (A) primarily produces insulin and glucagon to regulate blood sugar levels. The adrenal glands (B) produce hormones like cortisol and adrenaline to regulate stress response. The pituitary gland (D) controls various other endocrine glands but does not primarily produce hormones affecting metabolism.
Which of the following hormones helps conserve water during dehydration?
- A. Atrial natriuretic peptide
- B. Oxytocin
- C. Aldosterone
- D. Thyroxine
Correct Answer: C
Rationale: Aldosterone is the correct answer because it acts on the kidneys to increase reabsorption of sodium and water, helping conserve water during dehydration. Atrial natriuretic peptide promotes sodium excretion, oxytocin is involved in labor and milk ejection, and thyroxine regulates metabolism.