1. Organization of the Human Body – Organ Systems and Life-Span Changes
Chapter 1
Organization of the Human Body –
Organ Systems and Life-Span Changes

2. Organ Systems Integumentary System
Includes the skin and accessory organs such as hair, nails, sweat glands, and sebaceous glands
Protects underlying tissues
Helps regulate body temperature
Houses a variety of sensory receptors
Synthesizes certain products

3. Organ Systems Skeletal System
Includes, bones, ligaments, and cartilage
Provides a framework
Protects softer tissues
Serves as a place of attachment for muscles
Produces blood cells and stores inorganic salts in tissues within bones

4. Organ Systems Muscular System Includes muscles
Provides forces that move body parts (through contracting)
Helps maintain posture
Provides main source of body heat

5. Organ Systems Nervous System
Includes the brain, spinal cord, nerves, and sense organs
How the system works:
Nerve cells within the organs use electrochemical signals (called nerve impulses) to communicate with each other and with muscles and glands
Some nerve cells act as specialized sensory receptors that detect changes occurring within and outside the body
Other nerve cells receive impulses transmitted by the sensory nerve cells and act on the information
Still other nerve cells carry impulses from the brain or spinal cord to the muscles or glands , stimulating them to contract or to secrete specific product
The effect of the nerve impulse is relatively short-term

6. Organ Systems Endocrine System
Includes all the glands that secrete hormones (chemical messengers), including the pituitary gland, thyroid gland, parathyroid gland, adrenal gland, pineal gland, pancreas, ovaries, testes, and thymus
How the system works:
Hormones travel away from the glands in body fluids (such as blood) or tissue fluids
Usually the hormone will only affect a specific group of cells called target cells
The hormone affects the metabolism of the target cells
Effect of the hormone lasts for a long period of time

7. Organ Systems Cardiovascular System
Includes the heart, arteries, capillaries, veins, and blood
How it works:
Heart pumps blood through blood vessels
Blood transports gases, nutrients, hormones, and wastes
Carries oxygen from the lungs to all body cells
Carries nutrients from the digestive organs to all cells in the body
Transports hormones from endocrine glands to target cells
Carries wastes from body cells to the excretory organs

8. Organ Systems Lymphatic System
Includes lymphatic vessels, lymph fluid, lymph nodes, thymus, and spleen
Transports tissue fluid back into the blood stream
Carries certain fatty substances away from the digestive organs
Defends the body against infection by removing pathogens from tissue fluid (carried out by cells called lymphocytes)

9. Organ Systems Digestive System
Includes the mouth, tongue, teeth, salivary glands, pharynx, esophagus, stomach, liver, gallbladder, pancreas, small intestine, and large intestine
Breaks down food molecules into simpler forms that can pass through cell membranes and be absorbed into the internal environment
Transports unabsorbed materials outside
Some digestive organs can also produce hormones

10. Organ Systems Respiratory System
Includes the nasal cavity, pharynx, larynx, trachea, bronchi, and lungs
Takes air in and out
Exchanges gases between the blood and the air
Oxygen passes from air within the lungs into the blood
Carbon dioxide leaves the blood and enters the air

11. Organ Systems Urinary System
Includes the kidneys, ureters, urinary bladder, and urethra
How it works:
Kidneys remove wastes from the blood and assist in maintaining the water and electrolyte balance of the body, resulting in urine
Urine is stored and transported out of the body

12. Organ Systems Reproductive System
Male reproductive system includes the scrotum, testes, epididymides, ductus deferentia, seminal vesicles, prostate gland, bulbourethral glands, urethra, and penis
These structures produce, maintain, and tranfer spermatozoa
Female reproductive system includes the ovaries, uterine tubes, uterus, vagina, clitoris, and vulva.
These structures:
Produce, maintain, and transfer ova
Supports the development of embryos
Carry a fetus to term
Function in the birth process