Chronic renal failure causes hypocalcemia leading to PTH overproduction.

Lack of iodine decreases thyroid hormone synthesis.

Elevated prolactin inhibits gonadotropins causing infertility and gynecomastia.

Glucagon increases blood sugar by glycogen breakdown.

Addison’s disease increases ACTH leading to melanin deposition.

Corpus luteum produces progesterone to maintain pregnancy.

Cortisol exerts negative feedback on ACTH and CRH release.

GnRH is released in pulses to maintain FSH and LH balance.

Cortisol elevates during stress to maintain blood glucose.

Low sodium, high potassium, and low cortisol are diagnostic.

Zona glomerulosa produces mineralocorticoids, mainly aldosterone.

Aldosterone controls Na⁺ and K⁺ balance.

Deiodinase enzyme activates T4 into biologically active T3.

Estrogen promotes growth of endometrium and secondary female traits.

Excess ADH leads to water retention and hyponatremia.

Tumor of adrenal medulla producing catecholamines.

Negative feedback regulates insulin based on blood glucose levels.

Thyroid gland lies anteriorly in the neck below the larynx.

ADH acts on the collecting ducts of kidneys to increase water reabsorption.

ADH deficiency causes excessive urine output and thirst.

PTH increases calcium via bone resorption and kidney retention.

High prolactin levels cause spontaneous milk discharge.

ADH regulates reabsorption of water in kidneys.

Hyperthyroidism increases metabolism and causes eye protrusion.

Many peptide hormones act via cAMP, including glucagon.

Increased plasma osmolality triggers ADH secretion from posterior pituitary.

These are classic features of Cushing’s syndrome due to excess cortisol.

Parathyroid hormone (PTH) increases calcium by acting on bones, kidneys, and intestines.

Thyroxine determines oxygen consumption and heat production.

High TSH and low T4 levels confirm hypothyroidism.

Diabetes insipidus causes water imbalance due to ADH deficiency, not glucose abnormality.

Growth hormone (GH) affects tissues directly and also stimulates IGF-1 from the liver (tropic).

Suppression of adrenal cortex due to feedback inhibition.

Tumor compresses optic chiasma leading to bitemporal hemianopia.

Pituitary failure causes both low TSH and low T4 levels.

It is an autoimmune destruction of thyroid gland causing hypothyroidism.

GH suppression after glucose load is diagnostic of acromegaly.

Congenital hypothyroidism leads to mental retardation and stunted growth.

ACTH stimulation test distinguishes adrenal vs pituitary origin.

Accidental removal of parathyroid glands causes hypocalcemia.

GH excess before epiphyseal closure leads to gigantism.

Steroid hormones like cortisol are lipid-soluble and act through nuclear receptors.

It is due to adrenal cortex insufficiency causing low cortisol.

Prolactin from anterior pituitary stimulates milk production.

Growth hormone deficiency before puberty leads to pituitary dwarfism.

Type 1 Diabetes Mellitus due to insulin deficiency.

Thyroid gland regulates basal metabolic rate through thyroxine.

FSH promotes follicular development and estrogen secretion.

Testosterone develops beard, voice, and muscle mass.

Primary hyperaldosteronism leads to sodium retention and hypertension.