Human system docxptEndocrine_System.pptx

A comprehensive notes on human endocrine system and grands

1. The Endocrine System Complete Overview

2. What is the Endocrine System? • A communication and control system of the body • Uses hormones (chemical messengers) instead of electrical impulses • Hormones are secreted into the bloodstream • Provides slow but long-lasting control compared to the nervous system

3. Functions of the Endocrine System • Regulates growth and development • Controls metabolism • Governs reproduction • Manages response to stress • Maintains internal balance (homeostasis)

4. Major Endocrine Glands • Hypothalamus – controls pituitary • Pituitary – master gland (GH, TSH, ACTH, FSH, LH, Prolactin, ADH, Oxytocin) • Thyroid – thyroxine, calcitonin • Parathyroid – parathyroid hormone • Adrenal – cortisol, aldosterone, adrenaline • Pancreas – insulin, glucagon • Gonads – oestrogen, progesterone, testosterone • Pineal – melatonin

5. How Hormones Work • Bind to specific receptors on target cells • Steroid hormones: enter cells, affect DNA • Peptide/protein hormones: bind cell surface, activate enzymes

6. Regulation of Hormones • Negative feedback – common (e.g., thyroxine) • Positive feedback – rare (e.g., oxytocin in childbirth)

7. Endocrine Disorders • Diabetes Mellitus – insulin issues • Hyperthyroidism – too much thyroxine • Hypothyroidism – too little thyroxine • Cushing’s syndrome – too much cortisol • Addison’s disease – too little cortisol/aldosterone • Gigantism/Acromegaly – excess GH • Dwarfism – GH deficiency

8. Endocrine vs Nervous System Nervous System: • Electrical impulses, very fast • Short-lived effects • Targets specific neurons or muscles Endocrine System: • Hormones (chemical messengers) • Slower but long-lasting • Widespread effects via blood