Download 3.-the-heart-circulatory-system

National 5 Biology
Key Area 6:
The Need for Transport
(b) Animal Transport Systems
National 4 Biology
Key Area 4
Growth and Development of
different organisms
By the end of this lesson you will
be able to ....
• Describe the function of the circulatory
system in animals
• Describe (and be able to identify in a
diagram) the features of the heart and
associated vessels.
– To include right and left atria, left and right
ventricles, valves, aorta, vena cava, pulmonary
artery, pulmonary vein and coronary artery.
• Describe the pathway of oxygenated blood
through the heart, lungs and body.
• Describe the pathway of deoxygenated blood
through the heart, lungs and body.
The Circulatory System
• The circulatory system consists of the
heart (a muscular pump) and the blood
vessels (a system of tubes), which
carry essential materials (in the blood)
to all parts of the body.
External Structures
Vena Cava
(biggest vein
in body)
Coronary artery
- supplies the heart
muscle with
oxygen and glucose.
Aorta
(biggest
artery in the
body)
Internal Structures:
Chambers
The heart has 4 chambers.
Right
Atrium
(pl. atria)
Right
Ventricle
Left Atrium
(pl. atria)
Left
Ventricle
The left ventricle wall is
thicker than the right
ventricle wall because it
pumps blood all around the
body. The right ventricle
only pumps to the lungs.
Internal Structures:
Valves
• The heart has ___ valves.
• Valves help to ________ THE _________ OF BLOOD.
• They make sure the blood flows in ____ __________.
4
one direction
BACKFLOW
PREVENT
Valves
(between
ventricles
and vessels)
Valves
(between
atria and
ventricles)
Internal Structures:
Blood Vessels
• Veins carry _____________ blood ___________ the
heart.
• Arteries pump ___________ blood _________ from the
heart.
deoxygenated
away
Pulmonary Artery
towards
oxygenated
Aorta
Pulmonary
vein
(superior
and inferior)
Vena Cava
(superior
and inferior)
Right side –
deoxygenated blood
(low O2, high CO2)
Left side –
oxygenated blood
(high O2, low CO2)
Blood flow through the Heart
• http://www.kscience.co.uk/animations/h
eart.swf
Blood flow through the Heart
PULMONARY ARTERY
(TO LUNGS)
VENA
CAVA
(from the
body)
AORTA (TO THE BODY)
PULMONARY
VEIN (from
lungs)
Deoxygenated blood
Oxygenated blood
Cardiac muscle
The heart
has 4
chambers!
The “Double Circulatory” System
1. Deoxygenated
blood is pumped
from the heart to
the lungs in the
_______ _______
4. The oxygen
leaves the blood and
enters body cells.
Carbon dioxide
enters the blood
and it then goes
back to the heart in
the _______
2. The blood
receives oxygen
and is pumped back
to the _____
_____ of the
heart in the _____
_____
3. The oxygenated
blood is then
pumped to the rest
of the body in the
_______