This category explains the intracellular mechanisms by which hormones initiate responses inside target cells, focusing on second messenger pathways such as cyclic AMP and inositol trisphosphate.
During pregnancy, the placenta secretes progesterone, which helps maintain the uterine lining and prevent contractions.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
ADH (Vasopressin) helps in water reabsorption in the kidneys, reducing water loss in urine.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
ANF is a peptide hormone that causes vasodilation and reduces blood pressure by promoting sodium excretion.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
Leptin, secreted by adipose tissue, signals the brain to reduce hunger and regulate energy balance.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
Gastrin stimulates the secretion of hydrochloric acid and digestive enzymes in the stomach.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
Testosterone, secreted by the testes, is responsible for male secondary sexual characteristics such as muscle growth and voice deepening.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
Vasopressin (ADH) promotes water reabsorption in the kidneys, reducing urine output.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
Erythropoietin, secreted by the kidney, stimulates the bone marrow to produce red blood cells.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
Oxytocin, secreted by the posterior pituitary, stimulates uterine contractions during childbirth and milk ejection during lactation.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
Oxytocin is secreted by the posterior pituitary, not the anterior pituitary.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
Oxytocin plays a key role in the contraction of smooth muscles, especially during childbirth and milk ejection.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
Renin is secreted by the kidney and plays a crucial role in regulating blood pressure by activating the renin-angiotensin-aldosterone system (RAAS).
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Mechanism of Hormone Action - Second Messengers
