The Blood

Functions of the Blood Transport of gases, nutrients and

waste products Transport of processed molecules Transport of regulatory molecules Regulation of your ph and osmosis Maintenance of body temperature Protection against foreign substances Clot formation

Composition of Blood

Blood is Connective Tissue

Formed elements 45% Plasma 55%

Plasma

Pale yellow in color 91% water,7%proteins, 2% other ions,

nutrients gases and waste products The plasma proteins include albumin globulins fibrinogen

Formed Elements

95% are Red Blood Cells 5% are White Blood Cells and

Platelets Made through the process of

hematopoiesis derived from a single stem cell.

Red Blood Cell (RBC)

Biconcave Disk (shape important for function)

Loss their nuclei and most organelles

Live for 120 days in men and 110 in females

Contains hemoglobin( a red pigmented protein )

Main function to transport Oxygen

Hemoglobin

Oxygen Transport is accomplished through Hemoglobin (98.5% of Oxygen transport)

The Hemoglobin Structure Each protein (globin) is bound to one

heme Each Heme contains one iron atom When exposed to Oxygen one

Oxygen binds to the iron of each heme

Life History of a Red Blood Cell Low Oxygen Erythropoietin (kidney) Bone Marrow (Increased red cells) Increase Oxygen 120 Days Taken up by liver and spleen In liver broken down to heme and iron, amino acids Fe recycled by bone marrow Heme becomes bilirubin excreted out intestines

Fig11.4 and 11.5

Clinical Pearls: Anemia

Anemia is a common blood disorder, which occurs when the level of red blood cells (RBCs) in the body becomes too low.

What is the Physiologic Problem that will result?

Causes of Anemia

excessive destruction of RBCs blood loss inadequate production of RBCs Among many other causes, anemiaanemia can result from inherited disorders, nutritional problems (such as an iron or vitamin deficiency), infections, some kinds of cancer, or exposure to a drug or toxin.

Blood Grouping

Antigen/ Antibody Antigens are molecules that stimulate an immune response are on the surface of the red blood cells

Antibodies are proteins that recognize and neutralize the

immune response are present in the plasma.

Blood Grouping

The Antigens are categorized into blood groups

The ABO and RH blood groups are the

most important

The ABO Blood Group

Type A -Has type A antigens on the RBC Its Plasma Contains Anti-B antibodies Type B- Has type B antigens on the RBC Its Plasma Contains Anti- A antibodies Type AB-Has both types (A&B) on the RBC Its Plasma Has neither Antibody Type O – Has neither A or B on the RBC Its Plasma Contains both Anti A and

Anti B

http://go.hrw.com/resources/go_mk/sc/schst/HSTLVOCA.PDF

Antigens and Antibodies

Blood Type Antigens Antibodies

The Blood Transfusion Transfusion- is the transfer of blood or blood

components from one individual to another.

Donor- is the person who gives the blood

Recipient- is the person who receives the blood

Transfusion Reaction- When antibodies in the plasma of the recipient bind to antigens on the red blood cells of the donor, “molecular bridges” are formed that connect the red blood cells causing them to agglutinate and rupture the blood cells

Agglutination

“ Matchmaker, Matchmaker”

Rh (rhesus) Antigens Also on surface of the RBC Anti RH antibodies also circulate in blood Can be Rh- or Rh+ The ABO blood group and Rh are designated together A+ or A- B+ or B- AB+ or AB- O+ or O-

Important Implications during Pregnancy

Carbon Dioxide and OxygenTransport

70% of the carbon dioxide transported as HCO3

CO2 picked up by the red blood cells and converted by carbonic anhydrase

CO2+ H20------H + HCO3

Leukocytes (White Blood Cells)

Granulocytes Neutrophil Basophil Eosinophil Agranuloytes Lymphocyte Monocyte

Neutrophil Description- nucleus with four lobes connected by thin

filaments granules stain a light pink reddish purple

Function- Phagocyte “eats” microorganisms and other substances

Basophil

Description- Nucleus with two indistinct lobes,

cytoplasm granules stain blue

Function Releases histamine, which

promotes inflammation, and heparin (prevents clot formation)

Eosinophil

Description Nucleus often bilobed, cytoplasmic

granules stain orange-red or bright red

Function- Releases chemicals that reduce inflammation; attacks certain worm parasites

Agranulocytes

Lymphocyte Description round nucleus, cytoplasm forms a thin

ring around the nucleus- more cytoplasm to nucleus ratio

Function produces antibodies and other chemicals

responsible for destroying microorganisms , contributes to allergic reactions, graft rejection, tumor control, and regulation of the immune system

Monocyte Description Nucleus is round, kidney or horseshoe

shaped contains more cytoplasm than it does lymphocytes

Function- leave the blood and will enter

tissue , enlarge and become Macrophages which phaogcytize bacteria

and other debris

Clinical Focus

Leukemia- is a cancer in which abnormal production of one or more

of the white blood cell types occur Cells are immature and abnormal so

they lack their normal immunologic functions and people are more susceptible to infections

Platelets Also known as Thrombocytes Description- minute fragments of cells each

consisting of a small amount cytoplasm surrounded by a cell membrane Function- prevent blood loss a) by forming platelet plugs which seal

holes on small vesselsFormation of clots to seal larger vessels

Preventing Blood Loss

Vascular Spasm

Platelet Plugs

Blood clotting mechanisms

Control of Clot Formation

Natural – Fibrinolysis Medical - Anticoagulants