Module 2Exchange and transport

1.2.6 Structure of the mammalian heart

Starter

• Label the diagram of the heart – previous knowledge from KS4

•Label the structures of the heart(Grade E - D)

Learning Objectives Success Criteria

• To understand the structure of the mammalian heart

• Label the structures of the heart(Grade E - D)

• Describe with the aid of diagrams/photographs, the external and internal structure of the mammalian heart (Grade C –B)

• Explain the difference in the thickness of the walls of the different chambers of the heart in terms of their functions(Grade B – A)

(b)(c)

(a)

(f)

(d)

(h)

(e)

(g)

(k)(l)(j)

(m)

(i)

LEFTRIGHT

Pulmonary artery

Semi-lunar valve

Deoxygenated blood from the body

Vena cava (main vein)

Right atrium

Tricuspid valve

Papillary muscle

Right ventricle

Aorta (main artery)

Oxygenated blood from the body

Pulmonary vein

Left atrium

Bicuspid valve

Left ventricleTendons

•Label the structures of the heart(Grade E - D)

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The human heart

The heart is a muscular organ located between the lungs in the centre of the chest (thorax), and is about the size of a fist.

It pumps blood continuously around the body. An organism can lose conscious within just a few seconds if the brain is deprived of blood.

In foetuses, the heart begins beating about 5–6 weeks after conception.

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Cardiac muscle

The heart mainly consists of cardiac muscle tissue, which like smooth muscle (but not skeletal muscle), contracts involuntarily.

Cardiac muscle is made up of cells that are connected by cytoplasmic bridges. This enables electrical impulses to pass through the tissue.

It contains large numbers of mitochondria and myoglobin molecules.

Structure of the heart

•Explain the difference in the thickness of the walls of the different chambers of the heart in terms of their functions

(Grade B – A)

•Explain the difference in the thickness of the walls of the different chambers of the heart in terms of their functions

(Grade B – A)

•Explain the difference in the thickness of the walls of the different chambers of the heart in terms of their functions

(Grade B – A)

Can you identify the following without looking at your diagram? 1. The vessel which carries blood to the

lungs.2. The valve between the left atrium and

ventricle.3. The chamber which receives deoxygenated

blood from the body.4. The vessel which carries blood pumped out

of the left side of the heart.5. The vessel which carries blood into the heart

from the lungs.

Pulmonary artery

Bicuspid

Right atrium

Aorta

Pulmonary vein