A presentation on Blood Group & Rh antigens. NCERT - Class 11th standard topic.

1. BLOOD GROUPS
NIHARIKA DUBEY
DISTRICT CONSULTANT – NHM, MP

2. WHAT WE WILL LEARN?
 Introduction
 Blood Group Systems
 Types of Blood Groups

3. Introduction
 Blood is a fluid connective tissue and the
most crucial component of the circulatory
system.
 In a healthy person, approximately 5 litres
of blood circulates throughout their body.

4.  The main function of red blood cells is to
carry oxygen from the lungs to the body
tissues. And to carry carbon dioxide as a
waste product away from the tissues and back
to the lungs.
 Composition of blood is rather interesting…
 It consists of erythrocytes, leukocytes and
platelets suspended in plasma along with
the millions of different molecules with its
own specific roles and functions.
BUT WHY IS BLOOD SOO IMPORTANT TO OUR
BODY??

5. Blood Group Systems
 Karl Landsteiner, an Austrian scientist
discovered the ABO blood group system in the
year 1900.
 After series of clinical experiments, he divided
the blood types into 4 different groups.
 For the discovery of ABO blood group, he was
awarded the Nobel Prize.

6. But why do we need to care about
blood groups??
 The blood grouping system is pivotal in blood
transfusion. Our immune system recognizes
another blood type as foreign and attacks it if
introduced in the body causing a transfusion
reaction.
 Any inappropriate match with the Rh and ABO
blood types, causes the most serious and life-
threatening transfusion reactions.
 Therefore, before blood transfusion, it is
suggested to have a blood group checked.

7. Types of Blood Groups
 During the blood transfusion, the two most
important group systems examined are:
 The ABO-system and
 The Rhesus system.

8. The ABO Blood System
 The basis of ABO grouping is of two antigens- Antigen
A and Antigen B. The ABO grouping system is
classified into four types based on the presence or
absence of antigens on the red blood cells surface and
plasma antibodies.
 Group A – contains antigen A and antibody B.
 Group B –contains antigen B and antibody A.
 Group AB –contains both A and B antigen and no
antibodies (neither A nor B). (UNIVESAL ACCEPTOR)
 Group O – contains neither A nor B antigen and both
antibodies A and B. (UNIVERSAL DONOR)

9. The Rh Blood Group System
 About two-thirds of the population contains the
third antigen on the surface of their red blood cells
known as Rh factor or Rh antigen; this decides
whether the blood group is positive or negative.
 If the Rh factor is present, an individual is rhesus
positive (Rh+ve); if an Rh factor is absent individual
is rhesus negative (Rh-ve) as they produce Rh
antibodies. Therefore, compatibility between donor
and individual is crucial in this case as well.

10. What are blood group antigens
and antibodies?
The ABO system divides blood into four
major blood groups:
 Blood type A contains anti-B antibodies
and A antigens in the plasma.
 Blood group B contains anti-A antibodies
and B antigens in the plasma.
 Blood type O has both anti-A and anti-B
antibodies in the plasma but no antigens.
 Blood type AB lacks antibodies but
possesses both A and B antigens.

11. How are blood antibodies
formed?
 The immune system uses antibodies white
blood cells produce to recognise and combat
foreign elements in the body.
 Red blood cells have blood type antigens on
their surface, but the immune system does not
recognise them. However, antibodies will
recognise the antigens of a different blood
type as foreign and attack them.

12. THANK YOU!
ANY QUESTIONS?.......