THE ORGAN SYSTEMS

The Digestive System Breaks food down into chemical nutrients that body cells need for energy, growth & repair. Digestion begins in the mouth. Saliva helps to break down food that you are chewing. Travels down a long tube called the esophagus. Your stomach churns the food to help digest it a little more. Chemicals from your liver and pancreas help with digestion. Then, it travels into your small intestine. There are finger like bumps called villi that take the nutrients from the food and put it into your blood.

The Circulatory System Transports oxygen, nutrients and waste throughout your body. The heart: Like the engine. Pumps blood throughout your body. Without it, the blood would stay still. The blood vessels: Like the train tracks. Tubes that allow the blood to travel throughout the body. –Arteries: Bring blood away from the heart. –Veins: Bring blood back to the heart. –Capillaries: Are so small that blood cells can only move through them 1 at a time. The blood: Like the train. Carries the oxygen and nutrients throughout the body, dropping off and picking up at different locations.

The Respiratory System Exchanges oxygen and carbon dioxide between your body and your environment. Tiny nose hairs help to filter the air that you breathe in. Air travels down your trachea, also known as your wind pipe. This tube splits into 2 tubes called bronchi. They each lead to a lung, which inflates and deflates as you inhale and exhale. Tiny air sacs in your lungs, called alveoli, send oxygen into your blood. Carbon dioxide comes back through these air sacs so that it can be exhaled.

Skeletal System Gives your body its shape Protects your internal organs, like your heart, lungs and brain. Is made up of bones, cartilage and ligaments.

Muscular System Helps your body move. Made up mainly of muscles. –Skeletal muscles: These muscles are attached to your bones and help to support and move your body. Also known as VOLUNTARY MUSCLES. –Smooth muscles: These muscles make up most of the walls of your internal organs and blood vessels. Also known as INVOLUNTARY MUSCLES –Cardiac muscles: These muscles make up your heart. Also known as INVOLUNTARY MUSCLES.

The Nervous System Enables you to sense your environment and react to it. PERIPHERAL NERVOUS SYSTEM: Allows you to sense. –Is made up of: eyes, ears, nose, mouth, touch receptors in your skin. CENTRAL NERVOUS SYSTEM: Allows you to react. –Is made up of: brain, spinal cord and nerves.

The Excretory System Removes waste from the body. The kidneys are the main organs of this system. They help to filter waste. Waste flows through tubes called ureters and eventually reaches the bladder.