1.
In controlling aldosterone secretion, angiotensin II acts on which of the following structures?
Correct Answer
C. Zona glomerulosa
Explanation
Angiotensin II acts on the Zona glomerulosa in controlling aldosterone secretion. The Zona glomerulosa is the outermost layer of the adrenal cortex and is responsible for producing aldosterone, a hormone that regulates sodium and potassium balance in the body. Angiotensin II stimulates the Zona glomerulosa to produce and release aldosterone, which helps to increase sodium reabsorption and potassium excretion in the kidneys, leading to increased blood volume and blood pressure.
2.
Amino acids are most likely to produce the greatest increase in insulin secretion.
Correct Answer
A. True
Explanation
Amino acids are known to stimulate insulin secretion in the body. When amino acids are present in the bloodstream, they trigger the release of insulin from the pancreas. This is because insulin plays a crucial role in regulating the metabolism of amino acids. Therefore, it is likely that amino acids would lead to a significant increase in insulin secretion.
3.
Secretion of chemicals into the extracellular fluid by some cells results in actions upon cells in the same tissue. This is called:
Correct Answer
C. Paracrine
Explanation
Paracrine signaling refers to the release of chemicals by certain cells into the extracellular fluid, which then act upon nearby cells in the same tissue. Unlike endocrine signaling, which involves the release of hormones into the bloodstream to act on distant target cells, paracrine signaling is localized and affects cells in close proximity. Autocrine signaling, on the other hand, involves cells secreting chemicals that act on themselves. Therefore, the correct answer is paracrine.
4.
The following is not seen in Grave's disease.
Correct Answer
D. Increased Plasma TSH
Explanation
Grave's disease is an autoimmune disorder that leads to overactivity of the thyroid gland, resulting in excessive production of thyroid hormones. This excess production of thyroid hormones causes symptoms such as increased heart rate, increased plasma T3, and increased plasma T4. However, in Grave's disease, the immune system mistakenly produces antibodies that stimulate the thyroid gland, leading to a suppression of the production of thyroid-stimulating hormone (TSH) by the pituitary gland. Therefore, the correct answer is "Increased Plasma TSH" is not seen in Grave's disease.
5.
The thyroid hormone is a water-soluble hormone.
Correct Answer
B. False
Explanation
The thyroid hormone is not water-soluble, but rather lipid-soluble. This means that it is able to dissolve in fats and oils, but not in water.
6.
The following changes are seen in a patient with Conn's syndrome.
Correct Answer
B. Increased Aldosterone, Normal Cortisol
Explanation
In Conn's syndrome, there is an excess production of aldosterone by the adrenal glands. This leads to increased levels of aldosterone in the patient. However, cortisol levels remain normal in this condition. Cortisol is a hormone that is produced by the adrenal glands and is responsible for regulating various functions in the body. In Conn's syndrome, the primary abnormality lies in the overproduction of aldosterone and not cortisol, hence cortisol levels remain unaffected.
7.
Endocrine glands are derived from the following embryonic tissues.
Correct Answer
D. All of the above
Explanation
Endocrine glands are derived from all three embryonic tissues: ectoderm, mesoderm, and endoderm. The ectoderm gives rise to certain endocrine glands such as the pituitary gland, while the mesoderm contributes to the development of the adrenal gland. The endoderm is responsible for the formation of endocrine glands like the thyroid and pancreas. Therefore, all of the above embryonic tissues play a role in the derivation of endocrine glands.
8.
Posterior pituitary produces the following hormone.
Correct Answer
E. B&C
Explanation
The posterior pituitary gland produces two hormones: vasopressin and oxytocin. Vasopressin, also known as antidiuretic hormone (ADH), helps regulate water balance in the body by increasing water reabsorption in the kidneys. Oxytocin plays a role in various reproductive functions, such as stimulating contractions during childbirth and promoting bonding between individuals. Therefore, options B and C, which are vasopressin and oxytocin, respectively, are the correct answers.
9.
Ischemic necrosis of the pituitary following post partum hemorrhage is also known as:
Correct Answer
C. Seehan's Syndrome
Explanation
Seehan's Syndrome, also known as postpartum pituitary necrosis, occurs when there is ischemic necrosis (tissue death due to lack of blood supply) of the pituitary gland following postpartum hemorrhage. This condition can lead to hormonal deficiencies and can cause symptoms such as fatigue, low blood pressure, and inability to breastfeed. It is named after the physician who first described it, Dr. Robert Seehan.
10.
Insufficient thyroid hormone production in adults is called Cretinism.
Correct Answer
B. False
Explanation
The statement is false because insufficient thyroid hormone production in adults is not called Cretinism. Cretinism refers to a condition of congenital hypothyroidism in infants, where there is a lack of thyroid hormone production from birth. In adults, insufficient thyroid hormone production is known as hypothyroidism, which can have various causes and symptoms.
11.
Autoimmune thyroiditis is also known as:
Correct Answer
D. Hashimoto's Thyroiditis
Explanation
Autoimmune thyroiditis, also known as Hashimoto's Thyroiditis, is a condition in which the immune system mistakenly attacks the thyroid gland. This leads to inflammation and damage to the thyroid, resulting in an underactive thyroid or hypothyroidism. Graves Disease, on the other hand, is an autoimmune disorder that causes an overactive thyroid or hyperthyroidism. Myxedema is a severe form of hypothyroidism, while Cushing's Syndrome is a hormonal disorder caused by prolonged exposure to high levels of cortisol. Therefore, the correct answer for autoimmune thyroiditis is Hashimoto's Thyroiditis.
12.
Water and Electrolyte balance is maintained by hormones secreted by the adrenal medulla.
Correct Answer
B. False
Explanation
Water and electrolyte balance is not maintained by hormones secreted by the adrenal medulla. The adrenal medulla is responsible for secreting hormones such as adrenaline and noradrenaline, which are involved in the body's response to stress. The hormones involved in maintaining water and electrolyte balance are primarily secreted by the kidneys, such as antidiuretic hormone (ADH) and aldosterone. Therefore, the correct answer is false.
13.
Somatostatin is produced by the following cells of the pancreas.
Correct Answer
D. Delta
Explanation
Delta cells are responsible for producing somatostatin in the pancreas. Somatostatin is a hormone that inhibits the release of other hormones, such as insulin and glucagon. It helps regulate the levels of these hormones in the body, particularly during periods of fasting or low blood sugar. Delta cells are found in the islets of Langerhans in the pancreas, along with other cell types such as alpha, beta, and gamma cells.
14.
The normal sleep-wake cycle is disturbed when the following gland is destroyed.
Correct Answer
C. Pineal
Explanation
The pineal gland is responsible for producing melatonin, a hormone that helps regulate the sleep-wake cycle. When the pineal gland is destroyed, the production of melatonin is disrupted, leading to disturbances in the normal sleep-wake cycle. Therefore, the destruction of the pineal gland can result in a disturbed sleep-wake cycle.
15.
Obesity is usually seen in IDDM.
Correct Answer
B. False
Explanation
Obesity is not usually seen in IDDM (Insulin-Dependent Diabetes Mellitus). In fact, individuals with IDDM often have lower body weight due to the inability to produce insulin, which leads to difficulty in storing nutrients and energy. Therefore, the statement is false.