Endocrine System Overview

Components of the Endocrine System

• Brain: Hypothalamus, pineal gland, pituitary gland
• Neck: Thyroid gland, parathyroid gland
• Chest: Thymus gland
• Above Kidneys: Adrenal gland
• Near Stomach: Pancreas
• Gonads (Reproductive glands): Ovaries in females, testes in males

Endocrine vs. Exocrine Glands

• Endocrine Glands: Release hormones directly into the blood; no ducts needed.
• Exocrine Glands: Secrete substances through ducts to surfaces/cavities (e.g., sweat and mammary glands).

Memory Trick

• Endocrine: "Ender" - hormones enter the bloodstream.
• Exocrine: "Exiter" - secretions exit through ducts.

Dual Functionality

• Pancreas:
  • Endocrine: Releases insulin and glucagon to manage blood sugar.
  • Exocrine: Secretes digestive enzymes into the small intestine.

Hormones and Their Functions

• Derived from amino acids or lipids.
• Bind to specific receptors to trigger cellular actions (e.g., mitosis, enzyme activation).

Major Glands and Their Hormones

Hypothalamus and Pituitary Gland

• Posterior Pituitary Hormones: Store and release hormones from hypothalamus.
  • Oxytocin: Uterine contractions during childbirth.
  • ADH (Anti-diuretic Hormone): Promotes water reabsorption in kidneys.
• Anterior Pituitary Hormones:
  • Growth Hormone (GH): Promotes growth.
  • Prolactin (PRL): Stimulates milk production.
  • TSH (Thyroid Stimulating Hormone): Activates thyroid.
  • FSH (Follicle Stimulating Hormone): Stimulates ova/sperm formation.
  • LH (Luteinizing Hormone): Supports menstruation and ovulation.
  • ACTH (Adrenocorticotropic Hormone): Stimulates adrenal cortex.

Pineal Gland

• Melatonin: Regulates circadian rhythm (sleep-wake cycle).

Thyroid and Parathyroid Glands

• Thyroid Hormones (T3 and T4): Regulate metabolism.
• Calcitonin: Decreases blood calcium levels.
• Parathyroid Hormone (PTH): Increases blood calcium levels.

Thymus Gland

• Thymosin: Stimulates T cell production for immune response.

Adrenal Glands

• Adrenal Medulla:
  • Epinephrine and Norepinephrine: Fight or flight response.
• Adrenal Cortex:
  • Cortisol: Increases blood glucose, manages stress and inflammation.
  • Aldosterone: Regulates sodium and potassium balance.

Pancreas

• Insulin: Allows cells to absorb glucose, lowering blood sugar.
• Glucagon: Raises blood glucose by signaling liver to release glucose.

Gonads (Ovaries and Testes)

• Ovaries:
  • Estrogen: Promotes uterine lining growth, female sex characteristics.
  • Progesterone: Maintains uterine lining, supports pregnancy.
• Testes:
  • Testosterone: Essential for sperm production, male sex characteristics.

Additional Resources

• Visit nursechunkstore.com for more TEAS exam resources.
• Engage with questions for further understanding.