Download What are blood types?

What is blood?
• Blood is a mixture of several different
components that are responsible for
circulating nutrients, gases, and wastes
– It contains enzymes, cells, proteins,
hormones, and inorganic substances as well
as many other substances
• Fluid portion of blood is called plasma
Mostly water (55% of blood volume)
What makes up our blood?
• RED BLOOD CELLS (Erythrocytes) – The most abundant
cells in our blood; they are produced in the bone marrow and
contain a protein called hemoglobin that carries oxygen to our
cells.
• WHITE BLOOD CELLS (Leukocytes) – They are part of
the immune system and destroy infectious agents called
pathogens.
• PLASMA – This is the yellowish liquid portion of blood that
contains electrolytes, nutrients and vitamins, hormones,
clotting factors, and proteins such as antibodies to fight
infection.
• PLATELETS (Thrombocytes) – The clotting factors that are
carried in the plasma; they clot together in a process called
coagulation to seal a wound and prevent a loss of blood.
Blood Characteristics
•
•
•
Plasma is the fluid portion of the
blood (55%)
Cells (45%)
– Erythrocytes are red blood
cells. They are responsible for
oxygen distribution.
– Leukocytes are the white blood
cells; they are responsible for
“cleaning” the system of
foreign invaders.
– Thrombocytes or platelets are
responsible for blood clotting
Serum is the liquid that separates
from the blood when a clot is
formed.
Red blood cells
• Contain antigens on their surface
Proteins attached to the cells surface that
stimulate the body to produce antibodies
against it
• Humans have several different types of
antigens on their blood
– Most common = A or B
Historical Perspective
of Blood Typing
Around 1900, Karl Landsteiner discovered that there are four
different types of human blood based on the presence or
absence of specific antigens found on the surface of the red
blood cells.
In 1940, Landsteiner and Weiner reported the discovery of
the Rh factor by studying the blood of the Rhesus monkey.
85% of Caucasians, 94% of Black Americans and 99% of all
Asians are Rh positive.
Blood Terminology
• ABO blood groups based on having an A, B, both or no
antigens on red blood cells
• Rh factor may be present on red blood cells; positive if
present and negative if not
• Antigen  a substance that can stimulate the body to make
antibodies. Certain antigens (proteins) found in the plasma of
the red blood cell’s membrane account for blood type.
• Antibody  a substance that reacts with an antigen
• Agglutination  clumping of red blood cells; will result if
blood types with different antigens are mixed
A-B-O blood typing
• Fundamental principle in blood typing is
that for every antigen, there exists a
specific antibody
• Antibody – produced by the body’s
immune system when exposed to “foreign”
proteins (antigens)
– Found in the serum
A-B-O blood typing
• Antibodies are specific to the antigen
(protein) which elicited their formation
– Will not fight other antigens
• Works like a lock and key
Once antigen and antibody unite, creates a
antigen-antibody complex which is detectable
in the lab
What are blood types?
Blood Types
There are 3 alleles or genes for blood
type: A, B, & O. Since we have 2 genes,
there are 6 possible combinations.
AA or AO = Type A
BB or BO = Type B
OO = Type O
AB = Type AB
http://learn.genetics.utah.edu/units/basics/blood/types.cfm
Blood Typing
• Blood type A has antigen A on the surface of the
cell and will agglutinate with blood type B.
• Blood type B has antigen B on the surface of the
cell and will agglutinate with blood type A.
• Blood type AB has antigens A and B on the
surface of the cells and will not agglutinate with
either type A or B blood.
• Blood type O has neither antigen A or B and will
not agglutinate.
Blood Groups
Antibody Can Give
Can Get
Blood From
Type
Antigen
A
A
B
A, AB
O, A
B
B
A
B, AB
O,B
AB
A and B
Neither
A nor B
AB
A, B, O, AB
O
Neither
A nor B
A and B
A, B, O, AB
O
Blood To
How common is your blood type?
46.1%
38.8%
11.1%
3.9%