Your Heart & Blood

❤️ About your heart & blood (Circulatory system)

Your heart is a strong muscle pump about the size of your fist. Every beat pushes blood through a giant network of tubes called blood vessels.

Arteries carry blood away from your heart, full of oxygen from your lungs. Veins carry it back. The tiniest tubes, capillaries, reach almost every part of you.

Blood is always red. It carries oxygen and food to every cell, takes away waste, fights germs and patches up cuts. In the diagram we color the tubes that bring blood back blue, the way scientists do, so you can tell them apart.

• Heartbeats a dayabout 100,000
• Heart rooms4
• One trip around youabout a minute

• 🫀 Heart: Your heart is a strong muscle pump, about as big as your fist, that pushes blood all around you.
• 🏠 Heart rooms (Atria and ventricles): Your heart has four rooms: two on top where blood waits, and two below that pump it out.
• 🚪 Heart doors (Heart valves): Your heart has four little doors that open one way, so blood always flows in the right direction.
• 💓 Heartbeat (Pulse): Your heartbeat is the thump, thump of your heart pumping, and you can feel it in your wrist.
• 🎢 Aorta: The aorta is your biggest blood tube, carrying fresh blood from your heart out to your whole body.
• ↩️ Big veins (Vena cava): Two big veins called the vena cava bring used blood back into your heart.
• ➡️ Arteries: Arteries are strong, stretchy tubes that carry blood away from your heart to every part of you.
• ⬅️ Veins: Veins are tubes that carry blood back to your heart after it has dropped off its oxygen.
• 🕸️ Capillaries: Capillaries are the tiniest blood tubes, thinner than a hair, and they bring oxygen right to your cells.
• 🦒 Neck arteries (Carotid arteries): Your neck arteries carry fresh blood up both sides of your neck to your brain and face.
• ⬇️ Neck veins (Jugular veins): Your neck veins carry used blood from your brain and head back down to your heart.
• 🫁 Lung loop (Pulmonary circulation): Blood takes a quick loop from your heart to your lungs to grab fresh oxygen, then comes right back.
• 🩸 Blood: Blood is a red liquid that flows all through you, carrying oxygen, food and helpers to every part.
• 🔴 Red blood cells: Red blood cells are tiny red disks that carry oxygen from your lungs to every part of you.
• 🛡️ White blood cells: White blood cells are your body's guards: they find germs and fight them to keep you healthy.
• 🩹 Platelets: Platelets are tiny bits in your blood that rush to a cut and stick together to stop the bleeding.
• 💧 Plasma: Plasma is the yellowish, watery part of blood that carries the blood cells and lots of other things.
• 🅰️ Blood types: Blood comes in types like A, B, AB and O, passed down to you from your birth parents.