➤ Gonads are the primary reproductive organs.
➤ They produce sex hormones and reproductive cells.

➤ Testosterone is secreted by the testes in males.
➤ It is responsible for male secondary sexual characteristics.

➤ Estrogen is responsible for female secondary sexual characteristics.
➤ It regulates female reproductive development.

➤ Progesterone supports menstruation and maintains pregnancy.
➤ It prepares the uterus for implantation.

➤ Liver is the largest gland in the human body.
➤ It performs many functions including bile production and metabolism.

➤ Sweat glands are exocrine glands.
➤ They release sweat through ducts onto the skin surface.

➤ Salivary glands produce saliva.
➤ Saliva helps in digestion, lubrication and protection of the mouth.

➤ Ghrelin is known as the “hunger hormone.”
➤ It stimulates appetite and food intake.

➤ Pancreas is a heterocrine or mixed gland.
➤ It performs both endocrine and exocrine functions.

➤ Pancreas is the second largest gland in the human body.
➤ It releases both hormones and digestive enzymes.

➤ Islets of Langerhans are groups of endocrine cells present in the pancreas.
➤ These cells secrete hormones like insulin and glucagon.

➤ Alpha (α) cells of Islets of Langerhans produce glucagon.
➤ Glucagon converts glycogen into glucose (glycogenolysis).

➤ Beta (β) cells of Islets of Langerhans produce insulin.
➤ Insulin converts glucose into glycogen (glycogenesis).

➤ Insulin decreases blood glucose levels.
➤ It converts glucose into glycogen for storage.

➤ Glucagon increases blood glucose levels.
➤ It converts glycogen stored in the liver into glucose.

➤ Diabetes mellitus occurs when the body does not produce enough insulin.
➤ This leads to high blood glucose levels.

➤ Auxin promotes elongation of plant stems.
➤ It also helps maintain apical dominance.

➤ Gibberellin promotes seed germination and stem elongation.
➤ It also helps in flowering of plants.

➤ Cytokinin promotes cell division in plants.
➤ It also delays senescence (aging of plant tissues).

➤ Abscisic acid (ABA) inhibits plant growth.
➤ It acts as a stress hormone in plants.

➤ Ethylene is a gaseous plant hormone responsible for fruit ripening.
➤ It also helps regulate senescence and leaf fall.

➤ Tropic movements are growth-dependent movements in plants.
➤ They occur in response to stimuli such as light, gravity, water, and chemicals.

➤ Phototropism is the movement of plant parts in response to light.
➤ Shoots show positive phototropism by bending towards light.

➤ Geotropism is the movement of plant parts in response to gravity.
➤ Roots grow downward showing positive geotropism.

➤ Hydrotropism is the movement of plant roots towards water sources.
➤ Roots show positive hydrotropism.