Endocrine System
Biology · अंतःस्रावी तंत्र · 16 facts
Endocrine glands: ductless; secrete hormones directly into blood
Pituitary: master gland; controls other glands; in brain
Thyroid: neck; produces thyroxine(T4); needs iodine; controls metabolism
Iodine deficiency causes goitre(thyroid swelling); use iodized salt
Pancreas: dual function; insulin(lowers blood sugar)+glucagon(raises)
Diabetes: insufficient insulin; high blood sugar; discovered by Banting+Best
Adrenal glands: on kidneys; adrenaline(fight/flight hormone)
Adrenaline: increases heart rate, BP, energy in emergency
Growth Hormone(GH): from pituitary; excess=gigantism; deficiency=dwarfism
Testosterone: male hormone(testes); Estrogen: female(ovaries)
Parathyroid: 4 small glands on thyroid; calcium regulation in blood
Pineal gland: produces melatonin; regulates sleep-wake cycle
Thymus: important in childhood; T-cell development for immunity
Hormones: chemical messengers; act on specific target organs
Hypothalamus links nervous and endocrine systems
Exocrine glands have ducts: sweat glands, salivary glands