Overview
This lecture provides an overview of the 11 organ systems in the human body, organized by function, highlighting key organs and their main functions.
Categories of Organ Systems
- Organ systems are grouped by function: support/movement, integration/coordination, transport, absorption/excretion, and reproduction.
Support and Movement Systems
Integumentary System
- Organs: skin, hair, nails.
- Functions (PTSD): Protection (from pathogens/UV), Temperature regulation, Sensation, Vitamin D synthesis.
Skeletal System
- Organs: bones, joints (fibrous, cartilaginous, synovial), ligaments.
- Functions: structural support, levers for movement, protection of organs, blood cell production (bone marrow), mineral storage.
Muscular System
- Organs: skeletal muscles, tendons.
- Functions: movement, posture maintenance, heat production.
Integration and Coordination Systems
Nervous System
- Organs: brain, spinal cord, nerves, sensory receptors, sense organs (eyes, ears).
- Functions: fast communication/control, sensory processing, coordination of body functions.
Endocrine System
- Organs: hypothalamus, pituitary, pineal gland, thyroid, parathyroids, thymus, adrenals, pancreas, ovaries, testes.
- Functions: long-term communication/regulation using hormones, metabolism, calcium/blood sugar regulation, stress response, reproductive control.
Transport Systems
Cardiovascular System
- Organs: heart, blood vessels (arteries, veins, capillaries), blood.
- Functions: transport of oxygen, carbon dioxide, nutrients, hormones, waste.
Lymphatic and Immune System
- Organs: lymph nodes, lymph vessels, spleen, thymus, bone marrow.
- Functions: reduces tissue swelling, absorbs dietary lipids, immune response (defends against pathogens).
Absorption and Excretion Systems
Respiratory System
- Organs: lungs, diaphragm, nasal cavity, pharynx, larynx, trachea, bronchi, alveoli.
- Functions: gas exchange (oxygen in, carbon dioxide out).
Digestive System
- Organs: oral cavity, esophagus, stomach, small intestine, large intestine, rectum, anus, liver, gallbladder, pancreas.
- Functions: digestion (breakdown) of food, absorption of nutrients, elimination of waste.
Urinary System
- Organs: kidneys, ureters, bladder, urethra.
- Functions: removal of waste from blood, regulation of water, electrolytes, and blood pH.
Reproductive Systems
Male Reproductive System
- Organs: testes, epididymis, vas deferens, seminal vesicle, prostate, bulbourethral gland, penis.
- Functions: production and transport of sperm, hormone (testosterone) production.
Female Reproductive System
- Organs: ovaries, fallopian tubes, uterus, vagina.
- Functions: production and transport of eggs, support/nourishment of developing fetus, hormone (estrogen, progesterone) production.
Key Terms & Definitions
- Organ System — A group of organs working together for major body functions.
- Homeostasis — Maintenance of stable internal conditions.
- Hormone — Chemical messenger for long-term body regulation.
- Capillary — Smallest blood vessel where exchange of substances occurs.
- Lymph — Fluid transported in lymphatic vessels.
- Gamete — Sex cell (sperm or egg).
Action Items / Next Steps
- Download and complete the free study guide and practice exercises.
- Review and memorize the main organs and functions of each organ system.