An organ system is a group of organs that work together to perform one or more functions. Each system plays a vital role in maintaining homeostasis, the body's ability to maintain a stable internal environment
Watch our 5 minute animated video: 11 Human Body Systems in 5 Minutes
Definition: The integumentary system is the body's largest organ system, forming a protective barrier between the internal environment and the external environment.
Components: Skin, hair, nails, and glands such s sweat and sebaceous glands.
Major Functions:
- Protection from external threats (pathogens, UV radiation).
- Temperature regulation.
- Sensory perception (touch, pressure, pain).
- Vitamin D synthesis.
2. Skeletal System:
Definition: The skeletal system provides the body's structural framework.
Components:
Bones, cartilage, ligaments, and tendons.
Major Functions:
- Support and protection of internal organs.
- Movement (with the muscular system).
- Mineral storage (calcium, phosphorus).
- Blood cell production in bone marrow.
3. Muscular System:
Definition: The muscular system enables movement, maintains posture, and generates heat.
Components:
Skeletal muscles, smooth muscles, and cardiac muscle.
Major Functions:
- Movement (locomotion, manipulation).
- Posture maintenance.
- Heat generation.
4. Nervous System
Definition: The nervous system is the body's control center, coordinating and regulating bodily functions.
Components:
Brain, spinal cord, and nerves or neurons
Major Functions:
- Sensory perception.
- Motor control.
- Cognition (thought, memory).
- Regulation of other body systems.
5. Cardiovascular System:
Definition: The cardiovascular system transports blood, delivering oxygen, nutrients, and hormones throughout the body.
Components:
Heart, blood vessels (arteries, veins, capillaries), and blood.
Major Functions:
- Transport of oxygen, nutrients, and waste products.
- Regulation of body temperature.
- Immune response.
6. Lymphatic System:
Definition: The lymphatic system is part of the immune system, defending the body against infection.
Components: Lymph nodes, lymph vessels, spleen, thymus, and bone marrow.
Major Functions:
- Immune response.
- Fluid balance.
- Fat absorption.
7. Respiratory System:
Definition: The respiratory system facilitates gas exchange between the body and the environment.
Components:
Lungs, trachea, bronchi, and diaphragm.
Major Functions:
- Oxygen intake.
- Carbon dioxide elimination.
8. Digestive System:
Definition: The digestive system breaks down food into nutrients for absorption.
Components:
Mouth, esophagus, stomach, intestines, liver, pancreas, and gallbladder.
Major Functions:
- Digestion.
- Absorption of nutrients.
- Elimination of waste.
9. Urinary System:
Definition: The urinary system filters blood and eliminates waste products.
Components:
Kidneys, ureters, bladder, and urethra.
Major Functions:
- Waste elimination
- Fluid and electrolyte balance
- Blood pressure regulation
10. Endocrine System:
Definition: The endocrine system produces hormones that regulate various bodily functions.
Components:
Glands (pituitary, thyroid, adrenal, etc.).
Major Functions:
- Hormone production
- Regulation of growth, metabolism, and reproduction
11. Reproductive System:
Definition: The reproductive system enables sexual reproduction.
Components:
Male: testes, penis, etc.
Female: ovaries, uterus, etc.
Major Functions:
- Production of gametes (sperm in males and eggs in females).
- Hormone production.
- Support of fetal development in female.
Immune system:
Definition: The Immune system is not considered an organ system, but rather a complex
network of cells, tissues, and organs that work together to defend the body against infection and disease.
· Component:
Cells include White blood cells (leukocytes), lymphocytes (B and T cells), and other immune cells like macrophages.
Tissues are Lymph nodes, tonsils, and the spleen.
Major Organs of the immune system are bone marrow, thymus, and the lymphatic system. Proteins are Antibodies and other immune proteins like complement proteins.
Major Functions:
- Recognizing and destroying pathogens (such as bacteria, viruses, etc,)
- Distinguishing between the body's own cells and foreign invaders.
- Responding to and eliminating damaged or abnormal cells, such as cancer cells.