Human Body

Systems of Human Body

• Respiratory System• Nervous System• Skeletal System• Digestive System

Respiratory System

Parts of Respiratory System

• Lung • Trachea• Bronchi• Diaphragm

What is Respiratory System?

• Your respiratory system is made up of the organs in your body that help you to breathe. Remember, that Respiration = Breathing. The goal of breathing is to deliver oxygen to the body and to take away carbon dioxide.

What are Lungs?• The lungs are the main organs of the respiratory

system. In the lungs oxygen is taken into the body and carbon dioxide is breathed out. The red blood cells are responsible for picking up the oxygen in the lungs and carrying the oxygen to all the body cells that need it. The red blood cells drop off the oxygen to the body cells, then pick up the carbon dioxide which is a waste gas product produced by our cells. The red blood cells transport the carbon dioxide back to the lungs and we breathe it out when we exhale.

What is Trachea?• The trachea is sometimes called

the windpipe. The trachea filters the air we breathe and branches into the bronchi.

What is Bronchi?• The bronchi are two air tubes

that branch off of the trachea and carry air directly into the lungs.

What is Diaphragm?• Breathing starts with a dome-shaped muscle at the

bottom of the lungs called the diaphragm. When you breathe in, the diaphragm contracts. When it contracts it flattens out and pulls downward. This movement enlarges the space that the lungs are in. This larger space pulls air into the lungs. When you breathe out, the diaphragm expands reducing the amount of space for the lungs and forcing air out. The diaphragm is the main muscle used in breathing.

Nervous System

Parts of Nervous System

• Brain• Spinal Cord• Neurons

What is Nervous System?• The cells that make up the

nervous system are called neurons. Long, stringy neurons are perfect for carrying the electrical messages that are the "language" of the nervous system.

What is Brain?• The brain is the command center of your entire body. The brain is

the body's main information center. It is made of billions of neurons. The brain helps the body respond to the information it receives from the senses. The brain also processes thoughts. When you think, neurons in your brain are working.

• The brain has three main parts. The largest is the cerebrum, which controls vision, touch, and other senses. It also handles movements you have control over. Thinking takes place in the cerebrum. The cerebellum is another section of the brain. The cerebellum helps control balance and coordination. Another part of the brain is called the brain stem. The brain stem is the link to the spinal cord and it also controls digestion, breathing, and heartbeat.

What is Spinal Cord?• The spinal cord is a tube of neurons that

runs up the spine and attaches to the brain stem. Information from nerves that branch out to the rest of the body goes to the spinal cord. Some messages are processed by the spinal cord but most information is sent on to the brain.

What are Neurons?• The cells that make up the nervous

system are called neurons. Long, stringy

neurons are perfect for carrying the

electrical messages that are the

"language" of the nervous system.

Skeletal System

Parts of Skeletal System• Vertebrae• Cranium• Tendon• Ligament • Bone Marrow• Cartilage

What is Skeletal System?• Your Skeletal system is all of the bones in the

body and the tissues such as tendons, ligaments and cartilage that connect them.Your teeth are also considered part of your skeletal system but they are not counted as bones. Your teeth are made of enamel and dentin. Enamel is the strongest substance in your body.

Digestive System

Parts of Digestive System?

• Esophagus• Stomach• Small Intestine • Large Intestine

What is Digestion?• Digestion is the breaking down of food

into forms that our bodies can use. Our bodies use food as fuel to provide energy for work, play and growth. Your digestive system is responsible for converting the food we eat into energy for our bodies to use.

Where does the food go when we swallow?

• When we swallow the food goes into a tube called the esophagus. The esophagus is a muscular tube that is connected to the stomach. The muscles that surround the esophagus help to squeeze and push the food into the stomach.

Can we swallow if we are upside down?

• Yes, you can swallow upside down because the muscles around the esophagus are strong enough to push the food up to your stomach. I do not, however, recommend you try this anytime soon.

What about the stomach?• The stomach is a sack that receives the food

from the esophagus. Your stomach is located just below the heart. The stomach makes digestive juices (acids and enzymes) that help to break our food down into a thick liquid or paste. This thick liquid or paste is called chyme. Your stomach is a muscular organ that is able to move in order to mix the food with digestive juices. Food usually remains in the stomach for about two hours.

Where does the food go after it leaves the stomach?

• After leaving the stomach the food enters the small intestine. Your small intestine is a 20-25 foot tube that is coiled up in your abdomen. The center of your small intestine is right behind your belly button. The most important part of digestion takes place in the small intestine. As the thick liquid food paste travels through your small intestine the nutrients (vitamins, minerals, proteins, carbohydrates and fats) are absorbed by millions of tiny finger-like objects called villi and sent into your bloodstream where the nutrients can travel to all your body cells.

Does the body use all the food we eat?

• No, the body does not digest all the food that we eat. The undigested food leaves the small intestine and then enters the large intestine. The large intestine is about five feet long so it is shorter than the small intestine. The large intestine is however thicker or wider than the small intestine and that is why it is called the large intestine. I know, it doesn't make a whole lot of sense to me either.

So what does the large intestine do to the undigested food?

• The undigested food enters the large intestine as a liquid paste. In the large intestine water is removed from the liquid paste turning what is left into solid waste. Remember, liquid paste to solid waste. The solid waste then collects in the rectum at the end of the large intestine and will finally leave the body through an opening called the anus.

Thank You