Animals including Humans Year 6 Lesson 1 LI: describe the function of the heart.

Input What do you know about the heart? Where is it located? What is it made of? Why do we need it? What is its size?

The heart The heart made of a special muscle that never tires (gets tired). It beats itself without the brain having to control it. It started beating before you were born and will continue until death. The size of a human heart is similar to your clenched fist. It is protected by the ribs.

The function of the heart The heart is a powerful pump that sends the blood to every part of the body. Sometimes your heart changes its speed, getting faster or slower, depending on how much oxygen your body your body needs.

Inside the heart The heart divided into two halves separated but a wall of muscle. Each side of the heart is split into 2 chambers: The upper chamber is called the atrium The lower chamber is called the ventricle. There are valves that prevent the backflow of blood.

How the heart works Blood enters the right side of the heart via the Vena Cava (a vein) and enters the right atrium. The right atrium contracts (gets smaller) pushing the blood into the right ventricle (the bottom of the heart) When the right ventricle contracts, the blood is pushed to the lungs via the pulmonary artery. At the lungs the blood picks up oxygen. The blood is returned to the heart by the pulmonary vein and enters into the left atrium. Left atrium contracts sending the blood down into the left ventricle. When the left ventricle contracts, the blood is sent to the rest of the body via the aorta (artery).

What the heart looks like When you see a heart on paper it is reversed !

Activity Your task is to now label a heart with the following: 1.Left ventricle 2.Right ventricle 3.Right atrium 4.Left atrium 5.Pulmonary artery 6.Aorta

Plenary Listen to a heart beating. What do you notice? Why does the heart make the noise it does?