The Heart Pumps Blood All Around Your Body
Inside a cozy body-shaped room with glowing red pathways spreading out like roads, Medi holds a soft squishy heart model and squeezes it gently, sending tiny red drops traveling along the glowing paths to fingers, toes, and a smiling brain.
- Identify the heart as a body part found inside the chest, a little to the left.
- Explain that the heart's job is to push blood to all parts of the body.
- Describe what a heartbeat feels like when you place your hand on your chest.
- Demonstrate the squeezing motion of the heart by opening and closing your fist.
Key terms
- heart
- A muscle in your chest that pumps blood around your body.
- pump
- Something that pushes a liquid from one place to another.
- blood
- The red liquid that carries food and oxygen around your body.
- blood vessel
- A tiny tube that blood travels through inside your body.
- heartbeat
- One squeeze of your heart that pushes blood forward.
The Heart Is a Pump
Your heart is a muscle about the size of your fist, sitting in your chest a little to the left. It works like a pump, which is a machine that pushes liquid from one place to another. The liquid your heart pumps is blood, and every squeeze of your heart gives that blood a strong push forward through your body.
Blood Travels Everywhere
Blood moves through tiny tubes called blood vessels that reach every part of you. The heart pushes blood out to your fingers, toes, and brain, carrying food and oxygen they need. Then the blood loops back to the heart to get another push. This circle of pumping out and coming back happens over and over all day long.
Never Taking a Break
Your heart never stops, not even when you sleep, because your body always needs fresh blood. A child's heart beats roughly 70 to 100 times each minute while resting, and faster during play. You can feel each beat as a thump on your chest or a pulse on your wrist, proof that your heart is always at work.
Worked examples
Explain what makes the thump-thump on your chest.
- Each thump happens when the heart muscle squeezes.
- That squeeze pushes blood out into the blood vessels.
- So the thump-thump you feel is your heart beating.
Answer: The thump-thump is your heart squeezing to pump blood.
Decide whether the heart rests while you sleep.
- Your body needs blood all the time to stay alive.
- If the heart stopped, blood would stop moving.
- So the heart keeps beating even while you sleep.
Answer: No, the heart keeps beating all the time, even when you sleep.
Activity
Help Medi sort these pictures — which ones show a job the heart does?
Practice
Where in your body is your heart found, and what does it pump?
Why must your heart keep beating even while you are sleeping?
Common mistakes to avoid
- The heart rests when you sleep.The heart beats all the time, day and night, because the body always needs blood.
- The heart helps you breathe in air.Breathing is the lungs' job; the heart pumps blood that carries oxygen around the body.
Check your understanding
What is the main job of the heart?
Where is your heart found inside your body?
You put your hand on your chest and feel thump-thump. What is making that feeling?
Medi says the heart keeps working even when you sleep. Is that true?
Recap
Your heart is a muscle that works like a pump, pushing blood through tiny vessels to every part of your body and back again. It beats all the time, even while you sleep, because your body always needs fresh blood.
Reflect
How does it feel to find your own pulse, and why do you think it changes when you run?