2. What’s in
red blood cells white blood cells
platelets
plasma
carbon dioxide
digested food
waste (urea)
hormones
oxygen
3. Functions of Blood System
• Transport: to and from tissue cells
– • Nutrients to cells: amino acids, glucose, vitamins, minerals,
lipids (as lipoproteins).
– • Oxygen: by red blood corpuscles (oxyhaemoglobin - 4 x O2
molecules/haemoglobin).
– • Wastes from cells: urea, CO2 (mainly as HCO3 in solution in
the plasma).
• Temperature Regulation: by altering the blood flow
through the skin.
• Immunity: protection against pathogens — blood
clotting; phagocytes, lymphocytes and antibodies
distributed in blood.
• Communication: hormones distributed to all parts of the
body in the blood.
• Defence: clotting following a wound
4. The Blood
red blood cell white blood cell
plasma
platelets
5. Red Blood Cells
contain haemoglobin, a
molecule specially designed
to hold oxygen and carry it
to cells that need it.
a biconcave disc that is
round and flat without a
nucleus
can change shape to an
amazing extent, without
breaking, as it squeezes
single file through the
capillaries.
6. White Blood Cells
there are many different types and
all contain a big nucleus.
the two main ones are the
lymphocytes and the macrophages.
macrophages ‘eat’ and digest micro-organisms
.
some lymphocytes fight disease by making antibodies to destroy
invaders by dissolving them.
other lymphocytes make antitoxins to break down poisons.
7. Platelets
Platelets are bits of cell
broken off larger cells.
Platelets produce
tiny fibrinogen
fibres to form a net.
This net traps other
blood cells to form a
blood clot.
8. Plasma
A straw-coloured
liquid that
carries the
cells and the
platelets
which help
blood clot.
It also contains useful
things like;
• carbon dioxide
• glucose
• amino acids
• proteins
• minerals
• vitamins
• hormones
• waste materials
like urea.
12. Function of the
circulatory system
The circulatory system carries blood and dissolved
substances to and from different places in the body.
13. The Heart and blood vessels together make up the
Circulatory System.
The Heart pumps blood and substances around the
body in tubes called blood vessels.
The Heart has the job of pumping these things around
the body.
14. How does this system work?
lungs
head & arms
liver
digestive system
kidneys
legs
pulmonary artery
aorta
pulmonary vein
main vein
Right Left
Circulatory System
15. Our circulatory system is a double circulatory system.
This means it has two parts.
Lungs
Body cells
the right side of
the system
deals with
deoxygenated
blood.
the left side of
the system
deals with
oxygenated
blood.
16. Answer these questions:
Why do we say we have a double
circulatory system?
What is the Pulmonary circuit?
What is the Systemic circuit?
17.
18. blood from the heart gets around
the body through blood vessels
There are 3 types of blood vessels
a. ARTERY
b. VEIN
c. CAPILLARY
19. The ARTERY
Arteries carry blood away from the heart.
the elastic fibres allow
the artery to stretch
under pressure
thick muscle and
elastic fibres
the thick muscle can
contract to push the
blood along.
20. The VEIN
Veins carry blood towards from the heart.
veins have valves
which act to stop the
blood from going in
the wrong direction.
thin muscle and
elastic fibres
body muscles surround the veins
so that when they contract to
move the body, they also squeeze
the veins and push the blood along
the vessel.
21. The CAPILLARY
Capillaries link Arteries with Veins
they exchange materials
between the blood and
other body cells.
the wall of a capillary
is only one cell thick
The exchange of materials
between the blood and the
body can only occur through
capillaries.
22. A collection of capillaries is known as a ccaappiillllaarryy bbeedd.
23. SUMMARY
Complete the following text:
away
Arteries take blood ______ from the heart. The walls of an artery
are made up of thick _________ muscular
walls and elastic fibres. Veins
carry blood ________ the heart and also have valves. The
_________ link arteries and veins, and have a one cell thick wall.
Blood is made up of four main things ______, the liquid part of the
blood; Red Blood Cells to carry ______; White Blood cells to protect
the body from disease and _________ to help blood clot.
platelets
towards
capillaries
plasma
oxygen
24. Complete the table with the blood vessels differences.
Type of
blood
Direction Elastic
wall
Valves
ARTERIES
VEINS
CAPILLARIES
27. Explanation of Heart
Right
Atrium
Right
Ventricle
Left
Atrium
Left
Valves Ventricle
The heart has 4 chambers:
2 on the Right: received blood and 2 on the left: pumps the blood out
How does the heart pump?
What kind
of blood
does each
side
pump?
Which
side of
the heart
is thicker
29. The Heart
Artery to Lungs Artery to Head and Body
Right Atrium Left Atrium
Left Ventricle
valve
Right Ventricle
Vein from Lungs
Vein from Head and Body
valve
30. How does the Heart work?
blood from the
body
blood from
the lungs
The heart beat begins when the
heart muscles relax and blood
flows into the atria.
STEP ONE
31. How does the Heart work?
STEP TWO
The atria then contract and
the valves open to allow blood
into the ventricles.
32. How does the Heart work?
The valves close to stop blood
flowing backwards.
The ventricles contract forcing
the blood to leave the heart.
At the same time, the atria are
relaxing and once again filling with
blood.
STEP THREE
The cycle then repeats itself.
33.
34. What is DIASTOLE?
• The time period when the heart
is in a state of relaxation
What is SYSTOLE?
• It is a phase of the cardiac cycle
where the myocardium
is contracting
41. Some figures
• Your body has about 5.6 litres of blood.
• This 5.6 litres of blood circulates through the
body three times every minute.
• In one day, the blood travels a total of 19,000
km
that's four times the distance across the US
from coast to coast.
• The heart pumps around a third of a cup each
time it beats.
Editor's Notes
Overview of the main chambers of the heart
The left side is the thicker side because it has to pump blood all around the body
The left side pumps blood that has oxygen in it to the body
The right side pumps blood that has carbon dioxide in it to the lungs.
The heart pumps by squeezing it’s walls which are thick muscles.
Get some real sheep’s hearts from the butcher for the students to examine.
Give them 2 hearts per group:
One cut in half to see the inside chambers and one left intact to see the overall size and muscularity of the heart.
