12 Body Systems

1. Cardiovascular System

Consists of blood, heart, arteries, capillaries, and veins. Functions: Pumps blood to and from the heart to supply oxygen to the body

2. Digestive System

Organs include mouth, esophagus, stomach, liver, gallbladder, pancreas, small and large intestine, appendix and rectum. Functions: break down food, extracts nutrients from foods and deliver the products to the blood for dispersal to the body cells. And excretes waste products from the body.

3. Endocrine System

Produces chemical messengers and hormones into the blood, which direct the activities of different organ systems, regulate growth, development, and homeostasis.


Thyroid gland, Parathyroid gland, Adrenal glands, Pituitary gland, Hypothalamus, Pancreas (the part that produces insulin and other hormones), Stomach (the cells that produce gastrin), Pineal gland, Ovaries and Testes.

4. Eyes and Ears Sensory System

Provide vision and hearing and interpret visual and aural information about external conditions.

5. Immune and Hematology System

Bone marrow forms new blood and immune cells. Immune cells that fight pathogens and get rid of cancer cells. Red blood cells to carry oxygen around the body.

6. Lymphatic system

Lymph nodes, tonsils, thymus, spleen, a secondary circulatory system that helps the body fight pathogens and maintain its fluid balance.

 7. Musculoskeletal System

Muscles, Bones, Joints, Tendons and ligaments. Provides structure, support for other tissues and allows motion of the body.

8. Nervous System

Brain, Nerves, Spinal Cord, the body’s speedy, electrochemical communication system, consisting of all the nerve cells of the peripheral and central nervous systems. Enables thinking, self-awareness, and emotions.

9. Reproductive System

Organ system which functions in creating offspring (penis, prostate gland, seminal vesicles, vas deferens and testes in males; ovaries, uterus, cervix, fallopian tubes and vagina in females)

10. Respiratory System

Responsible for breathing. Parts: Lungs, pharynx, larynx, trachea, bronchi, lungs and diaphragm. Adds oxygen to the blood (and removes carbon dioxide from the blood).

11. Skin System

Organ system that includes hair, skin and the underlying structures of connective tissue, including fat, glands, and blood vessels and nails. Skin provides barrier protection between the inside of the body and the external environment. And provides sensory information and regulates body temperature.

12. Urinary System

Consisting of the kidneys, ureters, bladder, and urethra. Function: Filters waste products from the blood and removes wastes from the blood and helps to maintain water and electrolyte balance.