Living organisms are made up of cells .
This cells need oxygen and nutrients for their growth.
These are supplied through circulatory system.
In lower organisms like sponges and hydra circulation
is through water but in higher organisms it through
blood and lymph.
It has 90_92% of water,6_8% of proteins.
There are 3 types of proteins.
Fibrinogen –Helps in coagulation of blood.
Globulin-Involved in defense mechanism.
Albumin- Helps in osmotic balance.
It has minerals.
Plasma without fibrinogen is called serum.
Human RBC Is devoid of
Biconcave in shape.
Life span is 120 days.
Total count of RBC is 5-
Transport of respiratory
Total count 6000 to
TYPES OF LEUCOCYTES
• 2-3% of Leucocytes.
• Resist infections.
• Associated with allergic reactions.
• 60-65% of Leucocytes.
• Phagocytes in nature.
• It secretes histomine, serotonin& heparin.
• Involved in inflammatory reactions.
• It forms 20-25 % of formed element.
• It is of 2 types
• B-Lymphocytes &T-Lymphocytes.
• Both are responsible for immune responses of the body.
• These are phagocyte in nature .It forms 6 –8% of formed
Blood group Antigens Antibody DONATE
A A anti-B A,AB
B B anti-A B,AB
AB A,B -------- AB
O ------- Anti-
Another surface antigen is also present in
This surface antigen was first reported in
Rhesus Monkey. So it is called Rhesus
factor or RH factor.
80% of people are Rh+ve ,they have Rh
FEMALE * MALE
At child birth
Destroy the 2nd
As the blood passes through the capillaries in tissues, some
water along with many small water soluble substances move
out into the spaces between the cells of tissues leaving the
larger proteins and most of the formed elements in the blood
This fluid released out is called the interstitial fluid or tissue
This fluid present in the lymphatic system is called the lymph.
It has lymphocytes.
It is colorless.
Fats are absorbed through lymph.
• In this blood pumped by
the heart enters into
the open spaces called
• Blood flow is not
• In this blood is confined
to the blood vessels.
• Blood flow is regulated.
Structure of Human heart
It is located in thoracic
cavity in between 2
It is protected by
It has 4 chambers (2
Atria& 2 ventricles)
Heart is made up of
Right auricle is separated
from Right ventricle by
means of a septum with 3
flaps called tricuspid
Left auricle is separated
from left ventricle by
means of a septum with
2flaps called bicuspid
Cardiac cycle initiates from SA node(
Pace maker). It also maintains the
rhythm of heart beat.
It is located in the right upper corner of
From SA node the electrical impulses
reach the AV node.
AV node is located in the lower left
corner of the right atrium.
From AV node it reaches the Bundle of
Finally it reaches the ventricles
through Purkinjee fibers.
Human heart is myogenic in nature.
• It is the amount of blood pumped by heart
per minute is called heart output or
• Cardiac output =72x70 ml
TYPES OF BLOOD VESSELS
Carry blood from heart
to different parts of the
Valves are absent.
Have thick walls
Carry blood from
different parts of the
body to heart.
Valves are present.
Have thin walls.