Transcript The human circulatory system

Double circulation in mammals
Heart
Blood
The mammalian
circulation plan
Lung
Blood
vessels
pulmonary
circulation
systemic
circulation
All other parts
of the body
Circulatory
system
As blood
passes
through
heart twice,
this also
known as
double
circulation
The pulmonary circulation
3 The blood
becomes
oxygenated
1 Deoxygenated
blood in right
ventricle
2 The blood is
pumped
through
pulmonary
artery into lungs
for gas
exchange
4 The blood
flows through
pulmonary
veins to left
auricle
The human circulatory system
What’s wrong with him?
Tissue
fluid
RBC
plasma
body cell
capillary bed
The systemic circulation
3 O2 and
nutrients
diffuse into
cells while CO2
and wastes
diffuse out
1 Oxygenated
blood in left
ventricle
2 The blood is
pumped
through aorta
to all parts of
the body
except lungs
4 The blood
flows through
inferior/
superior vena
cava to right
auricle
The human circulatory system
The systemic circulation
After digestion
The blood flows
through inferior
vena cava back
to right auricle
Nutrients from the
small intestine
diffuse into the
blood
The blood flows
through hepatic
vein to liver
The human circulatory system
Formation of the tissue fluid
At arterial end :
Blood
 Osmotic
pressure pressure
arteriole
Tissue fluid
Plasma except RBC
and protein are
forced out of the
capillaries
tissue fluid
body cell
capillary bed
red blood cell
Formation of the tissue fluid
Tissue fluid is similar to blood
plasma but NO plasma
proteins and red blood
cells
Too large to be
forced through
capillary wall
tissue fluid
capillary bed
Formation of the tissue fluid
At venous end :
Blood
Osmotic

pressure pressure
some tissue fluid return
to capillaries by
osmosis.
lymph
venule
capillary bed
Lymphatic system
Transport of
tissue fluid back
into blood
circulation
Note: Exchange of Materials
It is carried out by diffusion through the whole length of
capillaries ( not tissue fluid formation)
(B.P. > O.P.)
(O.P. > B.P.)
substance pressed out
to the tissue cells
O.P.= osmotic
pressure
B.P.= blood
pressure
O.P.
substances diffused into
the blood capillary
O.P.
B.P.
arteriole end
B.P.
blood flow
venule end
The lymphatic system
Lymphatic system
Lymph vessels
Lymph
collect excess tissue
fluid and return them
to vein (blood
circulation) in neck
is the tissue fluid
inside lymph
vessels
Lymph vessels
Lymph capillaries collect
excess tissue fluid in the
capillaries beds.
tissue fluid
enters
Lymph capillaries from
different parts of the
body join to form lymph
vessels.
valve closed
Eventually, lymph is
returned to the blood.
lymph capillary
How lymph moves within lymph vessels?
Lymph flows in
similar way
Skeletal muscles
surround the
vessels contract
Do you remember
how blood flows
inside veins ?
Valves to prevent
backflow of lymph
Lymph nodes
lymph node
• swellings along the
lymph vessels
• presence of white
blood cells
– filter lymph
kill bacteria and
micro-organisms
lymph nodes
group of
lymph nodes
Functions of the lymphatic system
2 Transport of fats
4 As a site for body
absorbed from lacteals in
defence (lymph
intestinal villi into the
nodes)
blood
3 As a bridge for the
exchange of materials
between capillaries
and the tissue cells
(tissue fluid)
1 Transport of
tissue fluid back
into blood
circulation