Blood Physiology Lecture 7 Flashcards
2 components for classifying blood types
- ABO
- Rhesus Systems
What are blood types based on?
the antigens on the surface of RBC
What are the 4 blood types in the ABO system?
-A
-B
-AB
-O
The ABO class of antigens are _________
carbohydrate molecules
Blood group A has antigen type ____ on the surface of red blood cells
A
Blood group B has antigen type ___ on the surface of red blood cells
B
Blood Antigen AB has ______ on the surface of red blood cells
Both antigens A and B
Blood group O has _______ on the surface of the red blood cells
No surface antigens of the ABO type
What does an antibody combine with an antigen to form?
an antigen-antibody complex
An antibody is found in the _________ and recognizes a unique molecule called an _______
- blood
- antigen
indivuals also have ________ antibodies
plasma (blood)
What antibodies would someone have in their plasma if they are blood group A?
anti-B antibodies
What antibodies would someone have in their plasma if they are blood group B?
anti-A antibodies
What antibodies would someone have in their plasma if they are blood group AB?
no antibodies
What antibodies would someone have in their plasma if they are blood group O?
both Anti-A and Anti-B antibodies
antigens are found on surfaces of _______ while antibodies are found in ________
- Red Blood cells
- Blood
What dictates if a red blood cells is going to have a A, or B antigen?
So genes transfer their messages from DNA which transfers it to RNA which transfers it to a protein.
This protein then works as enzyme to attach the carbohydrate antigen to the RBC.
for ex. Gene A will give you Protein A that will facilitate antigen A to bind to the RBC
What are the dominant genes in heterozygous individuals?
Genes A and B are dominant over O in heterozygous individuals
Homozygous blood type A
AA
Heterozygous blood type A
AO
Homozygous blood type B
BB
Heterozygous blood type B
BO
Blood type AB genotype
AB genotype
Blood type O genotype
homzygous OO
How can you find blood type through experimentation?
Red blood cells of blood type A will clump when anti-A antibody is added, as they have the surface antigen A, but will not clump when anti-B antibody is present
Anti-B antibodies will clump cells of blood type B, etc.. (same type of thing as A)
With blood type AB, clumping will be observed when either anti-A antibodies, or anti-B antibodies are added
With blood type O, no clumping will be observed when either antibody is added
What is agglutination?
The process in which the surface antigens on the RBC are bound to antibodies to form a clump followed by Hemolysis, or the rupture or destruction of the RBC
Blood donors and recipient must be ____ before blood is transfused
-matched
Major cross-match
a test in which a donor’s red blood cell antigens are matched with the recepients plasma antibodies
When is a major cross match usually done?
When the donor’s red blood cells are seperated from the plasma fractions?
When is a minor cross match done?
When whole blood is transfused where the red blood cells are not seperated from the plasma, which contains antibodies, so the donor’s plasma antibodies must also be matched with the recipients RBC antigens to prevent agglutination
The best donor for blood is one whose _______ match with the recipents ______
- RBC antigens
- Blood Type
A donor of blood type O can donate to _________ in emergency situations
All blood types
Blood donors with blood type O are known as __________
universals donors
What blood type is known as universal recipients?
AB
Receipents of Blood Type AB do not possess any plasma _____ that can cause clumping of the donor’s RBC antigens
- antibodies
The two types of Rhesus blood types are:
- Rh+
- Rh-
What is classification of the Rh blood type based on?
The presence or absence of a protein on the surface of RBC known as the D antigen
What is the predominant Rh blood type?
Rhesus D positive (Rh+)
Antigens of the Rhesus system are ______ molecules and form an integral part of the RBC membrane
protein
Antigens of the Rhesus system are protein molecules and form an integral part of the RBC ______
membrane
The “D” antigens on the surface of the RBC is coded for by the _______
Dominant “D” gene
What does it mean if you do not have a dominant D gene?
An absence of the D antigen on the RBC so you will be Rh-
Possible phenotype(s) for Rh+
-Homozygous Dominant (DD)
-Heterozygous (Dd)
Possible phenotype(s) for Rh-
dd, homozygous recessive
Rh+ individuals have D antigens on the surface of RBC, and no __________ in plasma
anti-D antibodies
Rh- individuals have D antigens on the surface of RBC, and no __________ in plasma
anti-D antibodies
Anti-D antibodies are of the ____ class or immunoglobin G
igG
Anti-D antibodies are of the igG class or ___________
immunoglobin G
What is the exception where someone who is Rh- has anti-D antibodies?
When a Rh- person develops anti-D antibodiesd when they are accidentally exposed to D antigens during a blood transfusion or during pregnancy, in the case of a Rh- woman.
Are anti-D antibodies formed in the same manner by which our immune system reacts to exposure to a foreign bacterial antigen in developing antibodies?
Yes
Process of mismatched blood transfusion in Rh system
- Rh- Person with no anti-D antibodies is exposed to accidentally Rh+ blood during transfusion
- Rh- person develops anti-D antibodies
- Same Rh- person is exposeds to another transfusion of Rh+ blood
- Anti-D antibodies will bind to Rh+ RBC and cause clumping and hemolysis.
Rheusus mismatch causes a problem during pregnancy if the woman is _____
Rh-
What will happen if a Rh- women conceives with a Rh+ man?
She will carry an Rh+ baby in her pregnancy
Is a mother exposed to her baby’s Rh+ antigen in her first pregnancy?
no
What is the risk with having a Rh+ baby to a mom that has Rh-?
- During delivery of the baby, rupture of placental blood vesells causes some of the fetal Rh+ red blood cells to accidentally enter the maternal blood; which exposeds the baby’s Rh+ blood to the mothers immune system
- The mother then produces anti-D antibodies
- Then if the same woman gets pregnant again, her anti-D antibodies will pass through the placenta into the baby’s blood (who is Rh+) and bind to the baby’s red blood cells to cause rupture and hemolysis
- The baby is born with hemolytic disease of the newborn (HDN);
What is hemolytic disease of the newborn (HDN)
A disease when the baby is born with high levels of ruptured red blood cells with enlarged spleens and jaundice due to breakdown of hemoglobin
How can you prevent hemolytic disease of the newborn (HDN)?
by treating the mother after her first delivery with anti-Rh antibodies which will bind to all the red blood cells from the Rh+ newly delivered baby that have escaped into the mother’s body and are circulating in the mother’s blood, the baby’s red blood cells carrying D antigens are bound and blocked by anti-D antibodies and are not exposed to the mother’s immune system to sensitize her
