Blood Typing

Honors BiologyPowerpoint #3

What is in blood?

1) White blood cells

2) Platelets

3) Plasma

4) Red Blood Cells• Carry oxygen throughout body

• Determine blood type

Blood Typing Genotypes

Up to this point, we have talked about only 2 alleles for any gene (for example A or a)

In human blood types, there are 3 alleles: A, B and O

This is called multiple alleles

Blood Typing GenotypesSome rules in blood typing:

I is dominant to i

There are 6 possible genotypes, and 4 phenotypes

IAIA and IAi = blood type AIBIB and IBi = blood type BIAIB = blood type ABii = blood type O

What does your blood type mean?

Different blood types have

different SURFACE

PROTEINS on their

RED BLOOD CELLS

Glycoproteins on the surface of cells help identify “self”

The pattern of sugars that are attached is determined by a gene

Type A (IAIA and Iai)

An A allele (IA) tells

the cell to put

“A” glycoproteins

on its surface

Type B (IBIB and Ibi)

An B allele (IB) tells

the cell to put

different “B”glycoproteins

on its surface

Type O (ii) An O allele (i) tells

the cell NOT to put A or B

glycoproteins

on its surface

A cell with BOTH an A and a B allele has BOTH A and B glycoproteins on its

surface

Type AB (IAIB)

ANTIBODIES are specialized proteins that are part of your immune system. They react to, and attempt to destroy, ‘foreign’ invaders. Usually determined by their glycoproteins.

Glycoproteins on the surface of cells that cause animmune reaction are calledANTIGENS

How Antigens & Antibodies Interact

If you are blood type “A”, you have:

“A” Antigens AND “B” Antibodies

If you add ANTI-A (antibody A)

to cells with “A” glycoproteins on their surface, it causes them to

clump together

= ________________________AGGLUTINATION

Healthy blood cells vs Agglutinated cells

Adding ANTI-A

antibodies to cells

with B glycoproteins

on their surface

causes NO REACTION

How Antigens & Antibodies Interact

BLOOD TYPES

Will ANTI-A react?

NO YES NOYES

BLOOD TYPES

Will ANTI-B react?

NO NO YESYES

Blood Types

Blood Type:

PhenotypePossible

Genotypes Antigens AntibodiesCan give blood to

Can get blood from

A IAIA

IAiA B A, AB A, O

B IBIB

IBiB A B, AB B, O

AB IAIB A & B None AB A, B, AB, O

O ii None A & B A, B, AB, O

O

The A,B,O SYSTEM IS NOT THE ONLY ONE

Blood can also be Rh+ (positive) or Rh-(negative)

Rh Factor

If your blood does contain the Rh protein, your blood is said to be Rh positive (Rh+)

If your blood does NOT contain the Rh protein, your blood is said to be Rh negative (Rh-)

The Rh factor describes another surface protein on the RBC. It is named after the Rhesus monkey, where it was initially identified

Rh Factor

Similar to ABO blood types, an Rh- person may have the Rh antibody.

Therefore, Rh+ individuals can give blood only to other Rh+, but Rh- can give blood to both Rh+ and Rh-

So, O- is the ultimate donor!

BLOOD TYPES

Will ANTI-Rh react?YES

NO

You can determine the blood type of a cell by seeing which ANTIBODY it

reacts with

Add 1 drop of person’s blood to each well

Add 10uL ANTI-A serum to A well

Add 10uL of ANTI-B serum to B well

Add 10uL of ANTI-Rh to Rh well

You are looking for blood agglutination

Type A will clump in well A

Type B will clump in well B

Type AB will clump in both well A & B

Type O will NOT clump in A or B

Rh+ will clump in Rh well

Blood Typing Game