Transcript Blood

Blood
Functions of Blood
• Transports needed materials through body
– Nutrients like glucose and amino acids
– Oxygen
• Transports wastes through body to where
they are eliminated
– Carbon dioxide
– Metabolic wastes
Functions of Blood
• Help body defend against infection
– WBC and antibodies
• Help protect against injury through blood clotting
• Carry hormones to help regulate cell activities
• Help regulate body temp
• Help maintain body pH and water balance
Components of Blood
• Fluid
– Plasma
• Cells
– Red Blood Cells
– White Blood Cells
• Fragments of cells
– Platelets
Components of Blood
Where are Blood Cells Made?
– Blood Cells
• Produced in the
bone marrow of ribs
and long bones
Blood Plasma
• Fluid portion of blood (straw colored)
• About 90% water
• Has many things dissolved in it
– Proteins, vitamins, enzymes, glucose, amino acids, cellular
wastes, hormones, dissolved gases and salts
• Has fibrinogen which is involved in blood clotting
• Has antibodies which help fight infection
Red Blood Cells
• Carries oxygen from lungs to body tissues where
it is released at the capillary
• Contain hemoglobin
– Iron containing protein which carries oxygen
• Disc shaped
• They do not have a nucleus and therefore have
a limited life span
• Also called erythrocytes
Oxygen and
Hemoglobin
• Oxygen Transport in the Body:
• http://www.youtube.com/watch?v=WXOBJEXxNEo&safe=active
RBC Disorders
• Anemia:
– too few normal RBC
– not enough normal
hemoglobin
RBC Disorders
• Sickle Cell Anemia:
– Abnormal form of hemoglobin causes
abnormal sickle shape
– RBC doesn’t carry oxygen well and tend to
get stuck in capillaries causing pain
White Blood Cells
• Defend the body against
disease & infection from
bacteria, viruses and microbes.
• Help to provide immunity
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Only about 1% of blood
Also called leucocytes
Have a nucleus (unlike RBC)
Often larger than RBC
Produced in bone marrow and
lymphatic tissue
White Blood Cells
• Macrophages:
– Type of WBC that can move to affected areas to engulf
antigens through phagocytosis
– Engulf bacterial invaders, foreign substances and cancer
cells
•
http://www.youtube.com/watch?v=JnlULOjUhSQ&safe=active
• During infection WBC count increases
• Pus = consists partly of dead WBC
• Leukemia:
– Disease of the bone marrow
– Uncontrolled production of WBCs that don’t function.
– Considered to be a form of cancer
Platelets
• Involved in helping to form
blood clots after an injury
• Small bits of cytoplasm
without a nucleus
• Smaller than a RBC and
WBC
• Produced in bone marrow
• Only live about a week
Blood Clot Process
• Tear forms in blood vessel
• Platelets start to stick to
wound’s edges and to each
other at tear site
• Forms a “plug” that slows the
loss of blood within three to five
minutes.
• Release enzymes that help
clotting factors adhere to plug
and create a fibrous “clot”
• Clotting factors in blood reinforce platelet
“plug”
• Forms fibrin web that binds clot together
– Fibrin: protein fibers that form a sticky
network web over the wound
Blood Clot Formation
• http://www.youtube.com/watch?v=-bZUeb83uU&safe=active
• http://www.dnatube.com/video/29917/TheProcess-of-Blood-Clotting
Lymphatic System
• Lymph: portion of blood plasma that diffuses out
of capillaries.
– Surrounds the body cells as intercellular fluid (ICF)
between the cells
– Helps to transport dissolved material from capillaries
to cells
– Some reenters capillaries
– Some collects in lymph vessels
Lymphatic System
• Lymph Nodes:
– Act as filters trapping microorganisms and stray
cancer cells
– WBC in nodes destroy unwanted cellular material
– Remove bacteria and dead cells from circulatory fluid
– Can get swollen when you are fighting an infection
Blood Types
• A, B, AB, O
• Inherited from alleles from parents
– AA, AO
– BB, BO
– AB
– OO
Antigens and Blood Types
– Red blood cells have specific proteins in their
membranes
– Depending on your blood type, you have
different protein “antigens” present on your
blood cells
• Antigen:
– a normally foreign substance that stimulates an
immune response
• Antibodies:
– Produced by WBCs (lymphocytes)
– Recognize and attach to or “fit” specific antigens.
• Antibody/Antigen Response
– Your body will produce antibodies in response
to foreign antigens
– This is part of the “immune response”
Donating Blood
• You cannot give blood to or receive it from just
anybody.
– Depending on blood type you have different
antibodies in your bloodstream and different antigens
on RBCs
• The antigens and antibodies will react!!
• You have to receive blood of the right type or it
will agglutinate.
Blood Type Summary
Type A:
Antigens on blood cells =
Antibodies in plasma =
Donates to =
Receives from =
Type AB
Antigens on blood cells =
Antibodies in plasma =
Donates to =
Receives from =
Type B:
Antigens on blood cells =
Antibodies in plasma =
Donates to =
Receives from =
Type O
Antigens on blood cells =
Antibodies in plasma =
Donates to =
Receives from =
Rh Factor
• Rhesus Factor
– Another protein present on the RBC
– You can have it or not
– Rh positive or Rh negative
Review
• Which will develop an antibody antigen
reaction? Which will not?
– Type A person given type O
– Type AB person given type A
– Type O person given type B
– Type B person given type A
– Type A person given type AB