Created by Mrs. Groover West Ottawa Public Schools October, 2010 The Human Body Created by Mrs. Groover West Ottawa Public Schools October, 2010

The human body is made up of many different systems The human body is made up of many different systems. They work together to make the whole body work like a machine. We can study each system to better understand our bodies.

The Central Nervous System The nervous system has two parts. The central nervous system is made up of the brain and the spinal cord, which work together to analyze information and send messages to the body.

Three Parts of the Brain The cerebrum is the largest and controls the sense organs. It is responsible for thoughts, memories, imagination, and decisions. The cerebellum controls balance and posture, and coordinates movement. The brain stem connects the other parts of the brain to the spinal cord.

The Peripheral Nervous System The peripheral nervous system carries messages between the central nervous system and the body. Sensory nerves from the eyes, ears, nose, mouth, and skin give messages to the brain about what is happening outside the body. Motor nerves carry messages from the brain to the muscles.

Ten Steps to a Better Brain Regular bedtime Don’t sleep too much or too little Puzzles, problems, projects Exercise your heart Eat protein Eat calcium Eat breakfast Don’t drink caffeine Don’t take drugs Wear a helmet

The Circulatory System The circulatory system is made up of the heart, blood vessels, and blood. The circulatory system carries food and oxygen to the cells and removes waste.

The Heart The heart is a muscle that pumps blood throughout the body. It sends oxygen-rich blood from the lungs to different parts of the body. The heart also gets blood from different parts of the body and sends it to the lungs for oxygen.

Blood Vessels Arteries are the largest blood vessels. They carry blood from the heart to the body. Veins carry blood from the rest of the body back to the heart.

Blood Our blood is 55% (over half) plasma, a yellowish liquid. Red blood cells carry oxygen and carbon dioxide throughout the body. White blood cells fight infection. Platelets help the blood clot so we don’t lose too much blood when we bleed.

The Respiratory System The respiratory system includes the nose, mouth, trachea (windpipe), and lungs. Air enters through the nose or mouth, passes into the trachea, and goes to the lungs. The lungs have tiny air sacs called alveoli. A muscle called the diaphragm contracts and expands to help the lungs move air in and out.

Five Main Jobs Done by the Nose Moisture control Cleaning the air Temperature control Smell Sneezing Our nose has tiny hairs inside it called cilia. These help clean the air we breathe. Our nose also warms the air so it doesn’t hurt our lungs. Mucus helps trap dust and moisten the air.

The Skeletal System The skeleton gives the body shape and support. It also provides protection to important organs. For example, the cranium (skull) protects the brain and the ribs protect the lungs.

Bones An adult skeleton has 206 bones. The outer part of a bone is made of a hard material called compact bone. The inner part of a bone is a spongy material that contains bone marrow, which makes blood cells and stores fat for the body.

Get Connected A joint is where two bones meet. The hip and shoulder are ball and socket joints. The elbow is a hinge joint. Two bones are held together at a joint by ligaments. Ligaments are strong, stretchy fibers that keep bones in place.

The Muscular System There are more than 600 muscles in the human body. Muscles are attached to bones by tendons. The muscular system and the skeletal system work together to make it possible for the body to move.

Three Muscle Groups Skeletal muscles pull on bones to move them. They are voluntary muscles because we can choose to move them. Smooth muscles are found in organs in the body, such as the stomach. They are involuntary muscles because the nervous system directs them to move. The cardiac muscle can only be found in the heart. It contracts and relaxes about 70 times a minute without stopping or getting tired.

The Digestive System Our bodies need food for energy. The digestive system breaks food down so our bodies can use it. The mouth, esophagus, stomach, and intestines are all part of the digestive system.

How Digestion Works Teeth and saliva break food into smaller pieces in the mouth. The esophagus pushes food toward the stomach. The stomach breaks food down into a liquid and sends it to the small intestine, where the body absorbs nutrients from the food. The large intestine stores unused solids and sends waste to the rectum so it can leave the body.

The Integumentary System The integumentary system includes the skin, hair, and nails. It is the protective outer covering of the human body. This system helps control our body temperature. Skin is the largest organ of our body.

The Skin There are three layers of skin. The epidermis is the outer layer, made of dead skin cells which flake off. The dermis, the middle layer, has blood vessels and nerves. Hair follicles grow there. The subcutaneous layer is the fatty lower layer which attaches the skin to other tissues.

Functions of the Integumentary System Skin can: Act as a barrier to germs Control body temperature Allow you to touch/feel through nerves contained in the skin Allow hair & nails to grow Get rid of waste through sweat Produce oils to seal in water Hair can: Cushion us from minor blows Keep the sun off Provide warmth Keep dirt out of places it shouldn’t be (eyes, nose) Alert us to touch or temperature change

Caring for the Skin and Hair It is important to take care of your skin and hair so that they can continue to protect your body. Wash skin and hair regularly. Use sunscreen. Eat healthy foods and drink lots of water. Get enough rest and exercise regularly.

The Immune System Your body is exposed to thousands of germs every day. Your immune system fights germs to keep you from getting sick. Every time your body fights against a germ, it remembers how to fight against that infection if you get the same germ again.

Diseases A disease is when there is an upset or breakdown in body functions. Some diseases last only a short time, some can last a long time or be permanent. Some diseases can even cause death. Viruses can cause diseases like chicken pox, measles, influenza, and the common cold.

Ways Our Body Protects Itself Our skin keeps out many diseases and infections. White blood cells surround germs and kill them. The immune system produces chemicals called antibodies to fight against disease.

The human body is amazing and complex The human body is amazing and complex. Scientists study the many systems of the human body so that they can understand how to care for it.