The kidneys secrete all of the following hormones except_____________?
Show answer Hide answer
Answer: C. Vasopressin
Explanation
Vasopressin is synthesized by specialized neurosecretory cells within the hypothalamus. The posterior pituitary gland stores and releases this peptide into the systemic circulation. The kidneys respond to vasopressin rather than synthesizing or secreting the hormone. Antidiuretic hormone regulates water reabsorption in the collecting ducts of nephrons. Renal endocrine functions include producing renin, erythropoietin, and calcitriol. Hypothalamic osmoreceptors control the rate of vasopressin release into blood.
Deficiency in vasopressin production leads to the clinical condition diabetes insipidus. Renal responsiveness to circulating vasopressin is critical for maintaining body water balance. Measuring hormone levels helps differentiate causes of polyuria and fluid imbalance. Renin is secreted by juxtaglomerular cells in the renal afferent arterioles. Erythropoietin is synthesized by renal cortical interstitial cells to stimulate red blood cells. Dihydroxycholecalciferol is produced by renal tubular cells as active vitamin D.
Related questions
Q1. The chemical neurotransmitter released at the neuromuscular junction is_______________?
Show answer Hide answer
Answer: D. Acetylcholine
Acetylcholine is the primary neurotransmitter released by motor neurons at the neuromuscular junction. Nerve impulses trigger vesicle fusion and acetylcholine release into the synaptic cleft at motor end plates. Binding...
Q2. The most prevalent complication associated with blood transfusions is_______________?
Show answer Hide answer
Answer: A. Hemolytic reaction
Acute or delayed hemolytic transfusion reactions represent severe immunological risks caused by incompatible red blood cell group antigens. When mismatched blood is infused, recipient antibodies attack donor erythrocytes...
Q3. Total peripheral resistance is predominantly contributed by_________________?
Show answer Hide answer
Answer: B. Arterioles
Small arteries and arterioles provide the greatest resistance to blood flow in circulation. Their extensive smooth muscle walls allow active vasoconstriction and vasodilation adjustments. This high vascular resistance de...
Q4. The primary physiological action of secretin is to_____________?
Show answer Hide answer
Answer: D. Cause contraction of pyloric sphincter
Secretin primarily stimulates pancreatic duct cells to secrete large volumes of bicarbonate-rich fluid to neutralize gastric acid.
Q5. Oral and pharyngeal swallowing phases occur rapidly, lasting approximately______________?
Show answer Hide answer
Answer: B. 1-1.5 seconds
The oral and pharyngeal phases of swallowing are reflexive and rapid, taking about 1 to 1.5 seconds. Neurological coordination ensures that food passes swiftly through the pharynx to prevent airway aspiration. Rapid tran...
Q6. The nephron segment showing the lowest permeability to water is______________?
Show answer Hide answer
Answer: C. Ascending limb of loop of Henle
The thick ascending limb of the loop of Henle actively transports ions while remaining completely impermeable to water molecules. This specialized cellular impermeability allows the nephron to dilute tubular fluid as it...