Topic: Body Systems Pg. 3

Homeostasis: the process by which the body attempts to maintain a state of stable physiological (physical) balance. Pg. 3

How do we maintain a stable physical balance?

By making sure our body is carrying out all the needed functions in a consistent and healthy way.

What functions does the human body need to be able to do to stay alive and health?

Grow Get energy Get rid of waste Keep away diseases Respond to the changing environment Reproduce Repair injuries Absorb or break down things

Eleven Body Systems work together to maintain homeostasis and carry out those tasks: 1. Nervous System 2. Endocrine System 3. Lymphatic System 4. Circulatory System 5. Respiratory System 6. Digestive System 7. Excretory 8. Skeletal System 9. Muscular System 10. Integumentary System 11. Reproductive System

System Function Structures (3) Fact (1) Pg. 3

1. Nervous System Functions: A network of nerves and cells that carry messages to and from the brain and spinal cord to various parts of the body. Pg. 3

Facts about the Nervous System… Has two parts: central nervous system (CNS) and peripheral nervous system (PNS). The left side of human brain controls the right side of the body and the right side of the brain controls the left side of the body. The Nervous System can transmit impulses as fast as 100 meters per second.

2. Endocrine System Functions: Glands that produce hormones that regulate metabolism, growth and development, tissue function, sexual function, reproduction, sleep and mood

Hormone Examples and Functions… Growth hormone: promotes growth in children and for adults it helps to maintain healthy muscles and bones. Luteinizing hormone: In women, this hormone regulates estrogen. In men, it regulates testosterone. Thyroid-stimulating hormone: Just as the name implies, this hormone helps to regulate the body's thyroid, which is crucial in maintaining a healthy metabolism.

3. Lymphatic System Function: Helps keep bodies fluid levels in balance and defends the body against infections.

Facts about the Lymphatic System… Lymphatic vessels carry lymph (a clear, watery fluid containing protein molecules, salts, glucose, urea, and other substances) throughout the body. lymph nodes (small masses of tissue located along the network of lymph vessels) house lymphocytes (a type of white blood cell) Helps defend the body against germs like viruses, bacteria, and fungi that can cause illnesses

4. Circulatory System Functions: Network of organs and vessels that is responsible for the flow of blood, nutrients, hormones, oxygen and other gases throughout the body

Circulatory System Facts… The Circulatory System is also known as the Cardiovascular System and Cardiorespiratory System Arteries carry oxygenated blood (bright red) away from the heart to parts of the body while veins carry deoxygenated blood (dark red) back to the heart. Due to the heart having its own electrical impulse, it will continue to beat even when removed from the body as long as it has an enough oxygen.

5. Respiratory System Functions: A series of organs responsible for taking in oxygen, delivering it to the blood stream and expelling carbon dioxide.

Respiratory System Facts… Each of your lungs contains about 300 million balloon-like structures called alveoli, which replace the carbon-dioxide waste in your blood with oxygen. Yawning is a result of your body not taking in enough oxygen from the air, which causes a shortage of oxygen in our bodies. When we swallow, a flap of tissue (epiglottis) moves downwards to cover the trachea which prevents swallowed materials from entering the lungs.

System Function Structures (3) Fact (1) Pg. 5

6. Digestive System Function: A group of organs that work together to convert food into energy and basic nutrients to feed the entire body as well as get rid of solid waste.   Pg. 5

Digestive System Facts… Food can travel to your stomach in 7 seconds but the signal that tells your brain you are full will normally take about 20 minutes. The small intestine is about 20 feet long and 1 inch in diameter. Your large intestine is 5 feet long and 3 inches in diameter. The liver has over 500 different functions, one of which is producing bile to break down digestive fats Pg. 5

7. Excretory/Urinary System Functions: Removes waste from the human body that comes from your metabolism, cells and blood as well as helps control fluid balance. Pg. 5

Excretory System Facts… It takes about 45 minutes for your kidneys to completely filter all of the blood in your body. Most humans will urinate about 3,000 times per year if given a regular lifestyle The bladder can hold up to 24 ounces of fluid, or enough to fill up two standard cans of soda Pg. 5

8. Skeletal System Functions: This system supports the body, protects internal organs, assists with movement, stores minerals and provides a site for blood formation. Pg. 5

Skeletal System Facts… There are about 305 bones in a new born babies body but in an adult body there are 205. The majority of human bones have a strong outer layer, followed by a spongy/soft middle layer (bone marrow) where blood cells are produced. The smallest bones in the body is found in the middle of the ear (stapes) while the longest bone is found in the leg (femur) Pg. 5

9. Muscular System Function:  It allows for body movement, maintains posture, circulates blood and helps move food through the digestive system. Pg. 5

Muscular System Facts… There are 3 types of muscle tissues: cardiac (surround the heart), smooth (involuntary; surround organs), skeletal (voluntary; attach to skeleton) There are around 650 muscles in the human body Frowning is made possible by the working of 42 muscles, whereas smiling involves the contribution of 17 muscles. Pg. 5

10. Integumentary System (Skin) Functions: Consist of skin, hair, nails, glands, and nerves that function as a barrier to protect the body from the outside world, retain body fluids, protect against disease, eliminate waste products, and regulate body temperature. Pg. 5

Integumentary System Facts… Skin is the body's largest organ. Humans lose between 30,000 and 40,000 skin cells every hour. Melanin is pigment, which absorbs ultraviolet rays and determines skin color. The more melanin you have, the darker your skin is. Pg. 5

11. Reproductive System: Pg. 5 Function: In women, the organs that are directly involved in producing eggs and in conceiving and carrying babies; in men, the organs directly involved in creating, storing, and delivering sperm to fertilize an egg. Pg. 5

Reproductive System Facts… Out of billions of sperm cells found in semen, only one is used for fertilizing the female’s egg. Unlike men’s sperm, which are produced daily throughout a lifetime, woman are born with only one to two million immature eggs. Pg. 5