1 Why Do I Bleed

WHY DO I BLEED? WHY DO I?

Do You Need a Bandage? Have you ever cut your finger, had a bloody nose, or needed a bandage for your knee? What is that red stuff in your body, and what does it do? When you cut or scratch your skin, the red stuff that comes out is your blood. Blood is very important—and it's supposed to stay inside you! But what exactly is blood? Where does it come from?

What Is Blood For? All humans and most animals have blood inside their bodies. We need it to live. Blood has a lot of really important jobs to do. REALLY GOOD STUFF Blood travels all through our bodies. It carries useful things, such as oxygen, to the body parts that need them. Blood also heals cuts and helps protect us from illnesses. But how? Oxygen

Red or White? What is in your blood? Blood is made up of tiny parts called cells. Red blood cells carry oxygen around the body. White blood cells attack and destroy diseases and germs. Blood also contains material that helps heal cuts. The material clumps together to stop the blood from flowing out. A liquid in blood carries things such as nutrients around the body.

The Heart Pumps Blood Your heart is an organ. An organ is a body part that does a job. The heart's job is to pump your blood around your body. The left side of your heart is called the left ventricle. It sends blood full of oxygen from the lungs to the rest of the body. Left Ventricle The right side of the heart is called the right ventricle. It sends the used blood back to the lungs to be filled with oxygen again. Right Ventricle

Feel the Beat As your heart pumps the blood, it beats in a steady rhythm. If you listen to someone's chest, you will hear a bump-bump, bump-bump sound. This is called a heartbeat. BUMP BUMP BUMP BUMP A heart beats over 2.5 billion times in a person's lifetime!