Download Module 2 Exchange and transport

Module 2
Exchange 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
• Label the structures of the heart
(Grade E - D)
•
To understand the
structure of the mammalian • Describe with the aid of
diagrams/photographs, the
heart
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)
RIGHT
LEFT
Pulmonary artery
(a)
(c)
Semi-lunar valve
Deoxygenated blood
from the body
(d)
Vena cava (main vein)
Right atrium(f)
(b)
Aorta
(main artery)
Oxygenated blood
from the body
(e)
Pulmonary vein
(g)Left atrium
Tricuspid valve
(i)Bicuspid valve
Tendons
(j)
(k)Left ventricle
(h)
Papillary muscle(l)
(m)
Right ventricle
•Label the structures of the heart
(Grade E - D)
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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© Boardworks Ltd 2008
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.
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© Boardworks Ltd 2008
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)
Can you identify the following
without looking at your diagram?
1. The vessel which carries blood to the
lungs. Pulmonary artery
2. The valve between the left atrium and
ventricle.
Bicuspid
3. The chamber which receives deoxygenated
blood from the body.
Right atrium
4. The vessel which carries blood pumped out
of the left side of the heart.
Aorta
5. The vessel which carries blood into the
heart from the lungs. Pulmonary vein