2. Why do we need a Transport System?
Picture this…
3. Why do we need a Transport System?
Picture this…
• Nutrients transported to
cells
• Waste products transported
out of cell out of body
• Can Diffusion be the only way
to go?...
NO!
4. Why do we need a Transport System?
• We need a transport system to:
– Transport nutrients and oxygen to the various
organs/ cells
– Remove waste product efficiently
9. The Circulatory Fluid: Blood
Cellular Elements
• Red blood cells:
– Circular and biconcave with the centre portion
much thinner than the edge.
– This allows cells to be bent out of shape as they
squeeze through capillaries which are narrower
than themselves.
10. The Circulatory Fluid: Blood
Cellular Elements
– Mature red blood cells lack nucleus which allows
them to contain more haemoglobin.
– Relatively short life span of only three months.
– Replacement cells are produced by bone marrow.
11. The Circulatory Fluid: Blood
Cellular Elements
• White blood cells:
– All leucocytes have a nucleus.
12. The Circulatory Fluid: Blood
Cellular Elements
• White blood cells:
– The creeping movement of the white blood cell
enables it:
– To squeeze through pores in capillary walls in
order to reach the sites of infection, and
– To carry out phagocytosis in order to remove
bacteria or damaged cells.
14. The Circulatory Fluid: Blood
Cellular Elements
• White blood cells:
– During phagocytosis, cell processes surround and
engulf bacteria or damaged cells.
– Enzymes are then secreted into the vacuole formed
to digest it.
15. The Circulatory Fluid: Blood
Cellular Elements
• White blood cells:
– Inflammatory response:
– Injured cells release chemicals causing nearby
blood vessels to leak fluid into the tissue, causing
it to swell;
– This dilutes the toxins & brings extra oxygen as
well as platelets and clotting proteins to the
injured site;
– The chemicals also attract phagocytes which
engulf bacteria.
16. The Circulatory Fluid: Blood
Cellular Elements
• White blood cells:
– Inflammatory response:
17. The Circulatory Fluid: Blood
Cellular Elements
• White blood cells:
– Antibody production:
– Produced by lymphocytes;
– Antibodies will recognise antigen present on a
foreign body and bind with and deactivate that
specific antigen;
– Each antibody responds to a specific antigen;
– Some become memory cells for vaccination.
18. The Circulatory Fluid: Blood
Cellular Elements
• White blood cells:
– Antibody production:
19. The Circulatory Fluid: Blood
Cellular Elements
• Platelets:
– Smallest of the formed elements of blood.
– Between 250 000 to 400 000 platelets per mm3
of blood.
– Can live between five to eight days before being
destroyed by patrolling phagocytes.
– Used for formation of blood clot (platelet plug),
thereby preventing blood loss.
– Are highly adhesive to rough surfaces.
23. The Circulatory Fluid: Blood
Cellular Elements
• Platelets:
– Once the clot has
formed, it shrinks
and presses out
most of the fluid
serum.
– Clot hardens and
stops further
bleeding.
24. The Blood Vessels
• Three kinds of blood vessels are present in the human
circulatory system:
25. bloodVESSELS - artery
Structure:
•thick and elastic muscular walls to
withstand the high blood pressure
• elasticity enables artery wall to stretch &
recoil
• do not contain valves
Function:
•carry oxygeneated (except pulmonary
artery) blood away from the heart at high
pressure
Middle layer
(smooth muscle &
elastic fibres)
External layer
(connective tissue)
Small
lumen
26. bloodVESSELS - vein
Structure:
• relatively thin, less muscular
walls
• valves present to prevent the
backflow of blood
Function:
• usually carry deoxygenated
blood (except pulmonary vein)to
the heart at lower blood
pressure
28. Artery Vein Capillary
-Thick, muscular and
elastic walls to withstand
the high blood pressure in
artery.
-Elasticity allows artery
wall to stretch & recoil to
push the blood in spurts
along the artery.
-Thin, slightly muscular
and have less elastic tissue
as blood move more slowly
and smoothly in the vein at
low pressure.
- Very thin, only one-cell
thick wall to allow
exchange of substances to
take place between the
blood and surrounding
tissue.
-Valves are absent -Valves are present to
prevent backflow of blood
-No valves
-Always transport blood
away from the heart to the
rest of the body
-Transport oxygenated
blood(except for
pulmonary artery and
umbilical artery)
-Always transport blood
from body to the heart
-Transport deoxygenated
blood (except for
pulmonary vein & umbilical
vein)
-Always carry blood from
arterioles to venules
-Allow exchange of
substances between blood
and tissue fluid.
31. tissueFLUID (pure)
plasma
direction of
blood flow
movement of oxygen and
dissolved food substances
movement of excretory
waste products
blood capillary wall
white blood cell squeezing
through capillary wall
33. • Tissue cells are bathed in tissue fluid (interstitial
fluid)
• Tissue fluid allows the diffusion of dissolved
substances between the tissue cells and the blood
capillaries.
• Dissolved food substances and oxygen diffuse out
from the blood capillaries into the tissue fluid then
into the cells
• Excretory products diffuse out from the cells into
the tissue fluid and then through the capillary walls
into the blood.
36. • There are 4 human blood groups:
A, B, AB and O
• Classification is based on the types of antigens and
antibodies present in the blood:
Antigens represented by capital letters A & B
Antibodies represented by small letters a & b
38. Are ‘blood agglutination’ and ‘blood clotting’
similar?
Blood clotting is the formation of an enmeshed network
of fibrin that traps RBCs and seal the wound from further
blood loss.
Blood agglutination is the clumping of RBC when natural
antibodies in the recipient’s body react with the antigens
on the donor’s red blood cells.
40. Answers:
(a) X : Blood group B
Y : Blood group AB
Z : Blood group O
(b) Antibody b in the serum reacts with antigen B on the red blood
cells, causing clumping of the red blood cells from X.
(c) Blood group O
(d) Blood groups A and AB
(e) Such a person’s red blood cells do not contain any antigens, so
this person’s blood can be donated to any blood group without
causing clumping of the recipient’s red blood cells.
44. Double Circulation in Mammals
• In mammals, blood flows through the heart
twice in one complete circuit.
Systemic Circulation Pulmonary Circulation
46. Did You Know That?!
• The muscular walls of the right ventricle is
thinner than the left? Why?
-The left ventricle pumps
blood from the heart to
the rest of the body, thus
requiring a more muscular
wall.
-The right ventricle pumps
blood to the lungs, which
is nearer to the heart, thus
have a thinner muscular
wall
Right
Ventricle
Left
Ventricle
47. Aorta distributes oxygenated blood to
different parts of the body. For example...
Lungs
Liver
Small intestine
Kidney
Limbs
Aorta
Hepatic
artery
Renal
artery
Hepatic
vein
Hepatic
portal vein
Renal
vein
50. The Cardiac Cycle
1
The atria contracts, forcing blood into the
relaxed . This causes a slight
increase in both the atrial pressure and
ventricular pressure
1
ventricles.
51. The Cardiac Cycle
2
2
The Ventricles contract. This is called
ventricle systole. The ventricle pressure
increases. This causes the atrioventricular
valves (Tricuspid & Bicuspid valves) to
close, producing a loud “lub” sound and
prevents the backflow of blood into the
atria.
52. The Cardiac Cycle
3
3
The pressure in the ventricles becomes
higher than that of the aorta and
pulmonary artery. The semi-lunar valves
open and blood flows into the aorta and
pulmonary artery.
53. The Cardiac Cycle
4
4
The ventricles relax. This
is called ventricular
diastole. The drop in
pressure in the ventricles
causes the semi-lunar
valves to close, producing
a soft “dub” sound. This
prevents the backflow of
blood into the ventricles.
54. The Cardiac Cycle
5
5
The pressure in the
ventricle continues to
decrease as they relax.
6
6
The atrioventricular
valves opens as pressure
in the ventricle becomes
lower than that in the
atria.
7
7
The pressure in the
ventricles gradually
increases as blood
continues to enter the
ventricle from the atria
55. Heart Disease
• Coronary artery (supplies blood to the heart)
lie on the outside of the heart and supply
oxygenated blood to the muscles in the wall
of the cell.
56. • Taking in too much cholesterol and
polysaturated fat can cause fatty substance to
be deposited on the inner surface of the
coronary arteries.
Did You Know That?!
Atherosclerosis
57. Atherosclerosis
• This results in the occlusion/ blockage of the
coronary arteries and reducing the supply of
oxygenated blood & nutrients to the heart
muscles.
• Heart muscles eventually dies heart failure
Fatty deposits
Heart
Attack!
58. Buzz Time!
Can a thin person develop arteriosclerosis?
Polyunsaturated
fats
59. Effect of tobacco smoke
Substance Effect
nicotine increases blood pressure and the risk of
blood clotting in the coronary arteries.
carbon
monoxide
increase the risk of fatty deposits
(atherosclerosis) on the inner surfaces of
arteries.
60. Prepared by, Ms Wong Fui Yen
Examples of Famous People with Heart Disease
• Bill Clinton – quadruple
bypass surgery in 2004
• David Letterman -
quadruple bypass surgery
in 2000
• Larry King - heart attack
and bypass surgery in
1987
• Michael Jackson – died of
cardiac arrest 2009