MCQ Detailed View

Anti-Diuretic Hormone (ADH), also called Vasopressin, is a hormone secreted by the posterior pituitary gland. It plays a critical role in maintaining the body’s water balance and blood pressure by controlling how much water the kidneys reabsorb from urine back into the bloodstream. This helps reduce urine volume and conserve water, especially during dehydration or low blood volume.

ADH secretion is regulated by osmoreceptors in the hypothalamus that detect changes in blood concentration. When blood becomes too concentrated, these receptors signal the pituitary gland to release more ADH. Conversely, when blood is diluted, less ADH is secreted, allowing the kidneys to excrete excess water.

ADH also indirectly helps maintain electrolyte balance and blood pressure stability, making it vital for homeostasis. Disorders of ADH secretion can lead to medical conditions: diabetes insipidus occurs when there is insufficient ADH, causing excessive urination, while Syndrome of Inappropriate ADH Secretion (SIADH) results from too much ADH, leading to water retention and low blood sodium levels.

Other glands listed in the options are incorrect:

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  Pancreas secretes insulin and glucagon for blood sugar regulation.

  
  


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  Thyroid produces thyroid hormones for metabolism control.

  
  


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  Parathyroid regulates calcium levels via parathyroid hormone.

  
  

In summary, the pituitary gland secretes ADH, which is essential for water regulation, kidney function, and maintaining homeostasis in the human body. Understanding this hormone is fundamental in human physiology, endocrinology, and medical studies.