Nokea
Which factor stimulates insulin secretion?
- A. thiazide diuretics
- B. phenytoin
- C. theophylline
- D. β blockers
Correct Answer: C
Rationale: The correct answer is C: theophylline. Theophylline stimulates insulin secretion by increasing cAMP levels in pancreatic beta cells, leading to enhanced insulin release. Thiazide diuretics (A) can actually reduce insulin secretion. Phenytoin (B) and beta blockers (D) are known to inhibit insulin secretion. Therefore, theophylline is the only choice that directly stimulates insulin secretion.
You may also like to solve these questions
Hypothyroidism or an Underactive Thyroid Gland in Children Causes -------------------
- A. Goiter
- B. Acromegaly
- C. Myxedema
- D. Cretinism
Correct Answer: D
Rationale: The correct answer is D: Cretinism. Hypothyroidism in children can lead to cretinism, a condition characterized by stunted growth, intellectual disability, and other developmental delays. This occurs because thyroid hormones play a crucial role in growth and brain development during childhood. Goiter (A) is an enlargement of the thyroid gland, not a direct consequence of hypothyroidism in children. Acromegaly (B) is caused by excess growth hormone, not by hypothyroidism. Myxedema (C) is a condition seen in adults with untreated hypothyroidism, not specifically in children.
Why is the posterior pituitary gland called the neurohypophysis?
- A. The posterior pituitary gland is an extension of the hypothalamus.
- B. The neurohypophysis secretes releasing hormones.
- C. The posterior pituitary gland secretes hormones that regulate adenohypophyseal function.
- D. The posterior pituitary gland secretes releasing hormones.
Correct Answer: A
Rationale: The correct answer is A because the posterior pituitary gland is an extension of the hypothalamus. The hypothalamus produces hormones that are stored and released by the posterior pituitary gland. This connection between the two structures allows for direct neural control over hormone release.
Option B is incorrect because the neurohypophysis does not secrete releasing hormones; rather, it releases hormones produced by the hypothalamus. Option C is incorrect because the posterior pituitary gland does not regulate adenohypophyseal function; instead, it stores and releases hormones produced by the hypothalamus. Option D is incorrect because the posterior pituitary gland does not secrete releasing hormones; it releases hormones produced by the hypothalamus.
In addition to promoting the transport of glucose from the blood into the cell, what does insulin do?
- A. Enhances the breakdown of adipose tissue for energy
- B. Stimulates hepatic glycogenolysis and gluconeogenesis
- C. Prevents the transport of triglycerides into adipose tissue
- D. Accelerates the transport of amino acids into cells and their synthesis into protein
Correct Answer: D
Rationale: Insulin promotes the transport of glucose into cells and also enhances the transport of amino acids into cells, aiding protein synthesis.
A congenital condition that includes mental retardation, short disproportional body size, and a thick tongue and neck is caused by __________.
- A. insulin deficiency
- B. deficiency of thymosin
- C. deficiency of thyroxin
- D. excess of synthetic growth hormone
Correct Answer: C
Rationale: Step 1: The congenital condition described points towards a disorder affecting growth and development.
Step 2: The symptoms of mental retardation, short body size, and thick neck suggest hypothyroidism.
Step 3: Thyroxin is a hormone produced by the thyroid gland that regulates metabolism and growth.
Step 4: A deficiency of thyroxin in congenital hypothyroidism leads to the described symptoms.
Step 5: Therefore, the correct answer is C: deficiency of thyroxin.
Summary:
A: Insulin deficiency does not match the symptoms described.
B: Thymosin deficiency is not related to growth and mental retardation.
D: Excess of synthetic growth hormone would not cause mental retardation and thick neck.
A student is in a car accident, and although not hurt, immediately experiences pupil dilation, increased heart rate, and rapid breathing. What type of endocrine system stimulus did the student receive?
- A. humoral
- B. hormonal
- C. neural
- D. positive feedback
Correct Answer: C
Rationale: The correct answer is C: neural. In this scenario, the student experiences the fight or flight response, which is controlled by the sympathetic nervous system. The pupil dilation, increased heart rate, and rapid breathing are all physiological responses triggered by the activation of neural pathways in response to a perceived threat or stress. The other choices are incorrect because:
A: Humoral stimuli involve changes in blood levels of certain substances triggering hormone release.
B: Hormonal stimuli involve the release of hormones in response to other hormones.
D: Positive feedback is a mechanism that amplifies a response, not directly related to the immediate physiological responses seen in this case.