The human body consists of 11 major organ systems that work together to keep the body functioning properly. The key organ systems include the integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, digestive, respiratory, urinary, and reproductive systems. Each system is made up of various organs that work in coordination to carry out important tasks like protection, support, movement, coordination, regulation, transport, absorption, excretion, and reproduction.

1. Organ System Overview

2. Organ System The human organism consists of several organ systems. Each includes a set of interrelated organs that work together to provide specialized functions. Some organs function in multiple systems

3. Body Covering The Integumentary System : protect underlying tissues, helps regulate body temperature, houses a variety of sensory receptors, keeps pathogens out, and synthesizes certain products. Examples: The skin and various accessory organs, such as hair, nails, sweat glands, and sebaceous glands

4. Support & Movement The organs of the skeletal and muscular system support and move body parts. Skeletal System : bones, ligaments and cartilage that binds bones together Muscular System : muscles & tendons

5. Integration & Coordination The nervous and endocrine systems control and adjust various organ functions, which maintains homeostasis. Nervous System : brain, spinal cord, nerves, and sense organs Endocrine System : all the glands that secrete chemical messengers called hormones

6. Nervous System Nerve cells (called neurons ) within the body use electrochemical signals called nerve impulses to communicate with one another and with muscles and glands. Each impulse produces a fast response and last a relatively short time. Some neurons act as specialized receptors that detect changes inside and outside the body. (receptor) Some nerve cells receive the impulses transmitted form these sensory receptors and interpret and act on the information received. Some nerve cells carry impulses from the brain or spinal cord to muscles or glands, stimulating them to contract or to secrete products. (effectors)

7. Endocrine System All the glands in your body. Secrete hormones that travel throughout body in the bloodstream or in interstitial fluid. A particular hormone affects only a particular group of cells, called Target Cells . The affect of a hormone is to alter the metabolism of the target cells. Hormonal effects take longer to occur and last a relatively long time period.

8. Endocrine System Cont. Hormones regulate metabolism This system includes the pituitary, thyroid, parathyroid, and adrenal glands, as well as the pancreas, ovaries, testes, pineal gland, and thymus gland.

9. Transport 2 organ systems transport substances throughout the internal environment: Cardiovascular System : the heart, arteries, veins, capillaries, and blood Lymphatic System : lymphatic vessels, lymph fluid, lymph nodes, thymus gland, and spleen.

10. Cardiovascular System Blood transports gases, such as oxygen and CO 2 , Transport of nutrients, such as sugars, and waste Transport of hormones.

11. Lymphatic System Transports lymph fluid from tissues to the bloodstream. Carries certain fatty substances away from the digestive organs. Aids in defending the body against disease-causing agents.

12. Absorption & Excretion Organs in several systems absorb nutrients and oxygen and excrete various wastes. Digestive System Respiratory System Urinary System

13. Digestive System The digestive system receives foods, breaks down food molecules into nutrients that can pass through cell membranes, and eliminates materials that are not absorbed. It includes the mouth, tongue, teeth, salivary glands, pharynx, esophagus, stomach, liver, gallbladder, pancreas, small intestine, and large intestine.

15. Respiratory System The respiratory system takes in oxygen and sends out carbon dioxide. It includes the nasal cavity, pharynx, larynx, trachea, bronchi, and lungs.

16. Urinary System The urinary system includes the kidneys, ureters, urinary bladder, and urethra. It filters waste from the blood and helps maintain water, acid-base, and electrolyte balance.

17. Reproduction The reproductive systems produce new organisms.