blood group antigens and antibodies

Question 1

Proteins present on the surface of red cells

Answer 1

Red cell antigens

Question 2

Red cell antigens are

Answer 2

Inherited

Question 3

Most important red cell antigens

Answer 3

ABO and Rh

Question 4

Antigen A has antibody

Answer 4

B in plasma

Question 5

Antigen B has antibody

Answer 5

A in plasma

Question 6

Antigen AB has antibody

Answer 6

No antibodies present

Question 7

Blood group O has antibody

Answer 7

AB in plasma

Question 8

What are blood group antigens

Answer 8

Complex structures present on red cell membrane that contain proteins and carbohydrates and often have a role

Question 9

How are antigens produced

Answer 9

By the inheritance of certain genes which produce different antigen systems

Question 10

Where are blood group antigens located on membrane

Answer 10

Glycolipid, glycoprotein molecules on RBC

Question 11

The carbohydrate chain of membrane glycolipids carry antigens of

Answer 11

ABO,Hh,Li and P systems

Question 12

Band 3 contains ABO,Hh, Li antigens

Question 13

Glycophorin A contains these antigens

Answer 13

MN

Question 14

Glycophorin B contains

Answer 14

Ss and U antigens

Question 15

antibodies also called

Answer 15

immunoglobulins

Question 16

What are antibodies

Answer 16

Protein molecules found in the plasma/serum , produced by the immune system following exposure to foreign antigens

Question 17

An antibody binding to an antigen on the surface of the red cell results in

Answer 17

Red cell destruction

Question 18

What stimulates Antibodies

Answer 18

Blood transfusion, i.e blood carries antigens foreign to patient

Fetal antigen entering maternal circulation in pregnancy/ birth

Environmental factors

Question 19

Co dominant antigen include

Answer 19

A,B

Question 20

Most clinically important blood group system

Answer 20

A,B

Question 21

How are the ABO genes inherited

Answer 21

One from each parent, where the position 9 on each chromosome is occupied by either A,B OR O

Question 22

Blood group O antigen

Answer 22

Has no detectable antigen

Question 23

Blood group AB antibody

Answer 23

Has no detectable antibody

Question 24

Blood group O mode of inheritance

Answer 24

Autosomal recessive

Question 25

Why cant you inherit two O genes

Answer 25

Because it is inherited as autosomal recessive and doesnt code for any enzyme to add unto the terminal end of O antigen. Hence they just have H antigen

Question 26

Phenotype A can express genotypes

Answer 26

AA and AO because O has no antigens to be expressed

Question 27

Phenotype B has genotype

Answer 27

BB and BO

Question 28

Phenotype AB has genotype

Answer 28

AB

Question 29

pHENOTYPE OO has genotype

Answer 29

OO

Question 30

H antigen and blood grouping

Answer 30

It is the foundation upon which A and B antigens are built

Question 31

H gene function

Answer 31

It codes for an enzyme that adds a sugar i.e fucose to terminal sugar of a precursor substance to form H antigen

Question 32

How is precursor substance formed

Answer 32

On an oligossacharide chain, and contains lipids and carbohydrates

Question 33

How does H antigen become the foundation of A,B antigens

Answer 33

A and B genes code for enzymes that add sugar to the H antigen

Question 34

The does A gene add onto A ntigen

Answer 34

Codes for the enzyme N- acetylgalactosaminyltransferase which adds N-acetylgalactoseamine to the terminal sugar of H antigen

Question 35

How does B gene add on to H antigen

Answer 35

B gene codes for the enzyme D-galactosyltransferase that adds D galactose to the terminal sugar of the H antigen

Question 36

Enzyme that codes for conversion of H gene to H antigene

Answer 36

L-fucosyltransferase

Question 37

ABO antibodies show in humans from age

Answer 37

6 months

Question 38

IgM antibodies location

Answer 38

only in plasma , do not cross placenta

Question 39

IgM and compliment

Answer 39

Igm antibodies fix complement to C9 so transfusion is very severe

Question 40

Bombay phenotype

Answer 40

H gene not inherited and cant form H antigen to form ABO genes

Question 41

Bombay phenotype can be likened to this phenotype

Answer 41

Phenotype O and can be differentiated using anti-H i.e cos they dont have H antigen

Question 42

Varieties of rhesus

Answer 42

Dominant- C,D,E | Recessive - c,d,e antigens

Question 43

What is the rhesus factor

Answer 43

A group of agglutinogens that are also present on the surface of RBC

Question 44

Antigen with the strongest antigenic effect

Answer 44

Antigen D

Question 45

If antigen D is present

Answer 45

Rhesus positive

Question 46

If antigen D is absent

Answer 46

Rhesus negative

Question 47

Rhesus locus is located on

Answer 47

Long arm of chromosome 1 containing 2 genes RHC, RHCE

Question 48

Rh gene inheritance

Answer 48

Inherited as codominant alleles

Question 49

Most important blood grouping system after abo

Answer 49

Rhesus

Question 50

There is no

Answer 50

d antigen

Question 51

Rh (D) STAUS OF AN INDIVIDUAL IS USALLY EXPRESSED AS

Answer 51

Blood group antigen and the positive or negative suffix after ABO type

Question 52

Rh D frequency

Answer 52

5-10% in blacks 15% in UK 0.3% in chinese

Question 53

What happens when D negative people are exposed to D antigen

Answer 53

They produce anti-D

Question 54

When is anti -D stimulated

Answer 54

Transfusion | Feto maternal hemorrhage

Question 55

mOST IMPORTANT BLOOD GROUPING IN REGARDS TO HEMOLYTIC DX OF NEWBORN

Answer 55

RHESUS

Question 56

Most commonly produced Rh antibody after anti-D

Answer 56

ANTI-c

Question 57

Anti-c usually produced in these people

Answer 57

D positive cos they are highly likely to have antigen c

Question 58

In rhesus is you have the antigen

Answer 58

you will have the antibody