The Structure and Function of Blood

BloodThe circulating fluid of the body is BLOOD, a specialized connective tissue that contains cells suspended in a fluid matrix3 general functionsTransportationGases, nutrients, hormones, waste productsRegulationpH, body temperature, osmotic pressureProtectionClotting, white blood cells, proteins

Components of BloodBlood plasma water liquid extracellular matrix91.5% water, 8.5% solutes (primarily proteins)Hepatocytes synthesize most plasma proteinsAlbumins, fibrinogen, antibodiesOther solutes include electrolytes, nutrients, enzymes, hormones, gases and waste productsFormed elements- cell and cell fragments- RBCs (Red blood Cells) - WBCs ( white blood cells)- Platelets

Blood and lymph are connective tissues that contains distinctive collection of cells in a fluid matrix. In blood, the watery matrix is called PLASMARed Blood Cells, accounts for almost half the volume of blood. RBC transport oxygen in the blood.RBC contains small numbers of WBC, important components of the immune systemPlatelets, cell fragments that function in the blood clotting.

Composition of Blood

Blood is responsible for..Transporting gases (oxygen & carbon dioxide)Transporting waste products Transporting nutrientsHelping remove toxins from the body

Composition of Blood

Blood makes up 68% of our total body weight.

Normal adult blood volume is 5 L.

Blood is made up of cellular material in a fluid matrix called plasma.

Composition of Blood

Blood is a circulating tissue consisting of three types of cells.Red Blood Cells ErythrocytesWhite Blood Cells LeukocytesPlatelets Thrombocytes

The cells listed above are suspended in a liquid known as plasma.

Formation of Blood

Hematopoiesis the formation and development of blood cells

In adults the cellular elements are produced in the bone marrow.

Some WBCs are produced in the lymphatic tissue and bone marrow.

Blood cells need certain nutrients to form properly.

Examples include..IronFolic acidVitamin B12

All blood cells formed come from a hematopoietic stem cell.

These cells can become any blood cell.

Composition of Blood

The blood is made up of cells that are suspended in liquid called plasma.

Plasma makes up 55% of the blood.

Plasma is made of 90% water and 10% proteins, lipids, carbohydrates, amino acids, antibodies, hormones, electrolytes, waste, salts, and ions

Blood cells make up the remaining 45% of the blood.

Red blood cells make up 99% of the blood cells.

White blood cells and platelets make up the other 1%.

Composition of Blood

Each type of blood cell performs a different function.

Red blood cells (Erythrocytes)

White blood cells (Leukocytes)

Platelets (Thrombocytes)

Composition of Blood: Red Blood CellsRed Blood Cells

Stain pink-tan

Center of cell is lighter central area of pallor

Life span of about 120 days

Hemoglobin (iron protein)is found in the RBC

Hemoglobin carries oxygen from the lungs to the rest of the body and carbon dioxide binds to the RBC and is taken to the lungs to be exhaled.

http://www.giantmicrobes.com/us/products/redbloodcell.html

Composition of Blood: White Blood Cells

White blood cells Contain nuclei with DNA, the shape depends on type of cell

Certain WBCs produce antibodies

Life span is from 24 hours to several years

Size is 8-20 micrometers in diameter

There are five different types of WBCs Neutrophils Eosinophils Basophils Lymphocytes Monocytes

http://www.giantmicrobes.com/us/products/whitebloodcell.html

Composition of Blood: PlateletsPlatelets Involved in the clotting process

Seal wounds and prevent blood loss

Help repair damaged vessels

150,000 400,000 per microliter of blood

Platelets stain bluish with reddish or purple granules

The Blood Group Systems

Inheritance and Genetics

Karl Landsteiner discovered that blood clumping was an immunological reaction which occurs when the receiver of a blood transfusion has antibodies against the donor blood cells. Karl Landsteiner's work made it possible to determine blood types and thus paved the way for blood transfusions to be carried out safely. For this discovery he was awarded the Nobel Prize in Physiology or Medicine in 1930.History of Blood Groups and Blood Transfusions (Cont.)

General function of BloodTransportationRegulationProtectiona.) Material transported by the blood include nutrients, waste products, gases and hormones.b.) The blood helps regulate fluid-electrolyte balance, acid-base balance, and body temperature.

PROTECTION- against pathogens is provided by white blood cells, and the blood clotting mechanism prevents excessive loss of blood after injuries

ColorArterial blood is bright red because it contains high level of oxygen

Venous blood has given up much of its oxygen in tissue, and has a darker, dull red color.

If blood is bright red, it is probably from a several artery, and dark red blood is probably venous blood.

pH and viscositypH- normal pH range of blood is 7.35-7.45 which is slightly alkaline.Venous blood normally has a lower pH than does arterial blood because of the presence of more carbon dioxide.Viscosity- thickness or resistance to flow.blood is about 3-5 thicker than water. Viscosity is increase by the presence of blood cells and the plasma proteins, and this thickness contributes to normal blood pressure

PlasmaIs the liquid part of blood and is approximately 91% water.Most of the carbon dioxide produced by cells is carried in the plasma in the form of bicarbonate ions,Also in the plasma are the , plasma proteins. The clotting factors prothrombin, fibrinogen, and others are senthesized by the liver and circulate and activated to form a clot in a ruptured blood vessel.

ALBUMIN- the most abundant plasma protein.Contributes to the colloid osmotic pressure of the blood which pulls tissue fluids into the capilliaries, this is important to maintain blood volume and blood pressure.Other plasma proteins are called globulins..Alpha and beta globulins are synthesized by the liver. The gamma globulin are antibodies produced by lymphocytes.Antibodies initiate the distruction of pathogens and provide us with immunity

Blood cells3 kinds of blood cellsRed blood cellsWhite blood cellsPlateletBlood cells are produced from stem cells in hemopoietic tissue, after birth this is primarily the red bone marrow, found in flat and irregular bone such as the sternum , hip bone and vertebrae.

Red Blood CellsAlso called erythrocytes, red blood cells(RBCs) are binconcave disc, which means their centers are thinner than the edges.Red blood cells are the only cells without nuclei.Their nuclei disintegrate as the red blood cells mature and are not needed for normal functioning.

Normal RBC count ranges from 4.5-6.0 million cell per microliter of blood.Hematocrit range is just like that of the total blood cells, 38% to 48%. Both RBCscountand hematocrit are part of a complete blood count.FUNCTION:Red blood cells contain protein hemoglobin which givesthem the ability to carry oxygen.Red blood cells contain approx. 300 million hemoglobin molecules, each of which can bond to four oxygen molecules.

Red blood cells are formed in the bone marrow in the flat and irregular bones. Within red bone marrow are precursor cells called stem cells.The stem cell of the bone marrow may also be calle hemocytoblast (hemo=blood. Cyto=

The differences in human blood are due to the presence or absence of certain protein molecules called antigens and antibodies.

The antigens are located on the surface of the RBCs and the antibodies are in the blood plasma.

Individuals have different types and combinations of these molecules.

The blood group you belong to depends on what you have inherited from your parents.

What are the different blood groups?

There are more than 20 genetically determined blood group systems known today

The AB0 and Rhesus (Rh) systems are the most important ones used for blood transfusions.

Not all blood groups are compatible with each other. Mixing incompatible blood groups leads to blood clumping or agglutination, which is dangerous for individuals.

What are the different blood groups?

According to the ABO blood typing system there are four different kinds of blood types: A, B, AB or O (null). ABO blood grouping system

Blood Typeshttp://www.bloodbook.com/world-abo.html

AB0 blood grouping system

The "A and "B" antigens are also produced by some other plants and microorganisms. Thus, individuals who do not recognize one or more of these antigens as "self" will produce antibodies against the plant or microbial antigens.

These antibodies will also react with human antigens of the same kind whether introduced via a blood transfusion or a tissue graft.

Why do individuals produce antibodies to antigens they do not have?

The ABO gene is autosomal (the gene is not on either sex chromosomes)

The ABO gene locusis located on the chromosome 9.

Each person has two copies of genes coding for their ABO blood group (one maternal and one paternal in origin)

Aand B blood groups are dominant over the O blood group

A and B group genes are co-dominant

ABO inheritance and genetics

AUTOSOMAL CHROMOSOMEPeteSusanone alleles from Pete and one from Susan.The alleles for Blood group are in the same place on the chromosome 9. However the genes have a different code giving the different blood groupAB

This meant that ifa person inherited one A group gene and one B group gene their red cells would possess both the A and B blood group antigens.

These alleles were termed A ( which produced the A antigen ), B (which produced the B antigen) and O (which was "non functional"and produced no A or B antigen)

What do co-dominant genes mean?

Possible Blood group Genotypes

ParentAlleleABOABO

Possible Blood group Genotypes

ParentAlleleABOAAAABAOBABBBBOOAOBOOO

The ABO blood groups

The most important in assuring a safe blood transfusion.

The table shows the four ABO phenotypes ("blood groups") present in the human population and the genotypes that give rise to them.

Giving someone blood from the wrong ABO group could be fatal.

The anti-A antibodies in group B attack group A cells and vice versa. Blood group O negative is a different story.

Well, it gets more complicated here, because there's another antigen to be considered - the Rh antigen. Some of us have it, some of us don't. If it is present, the blood is RhD positive, if not it's RhD negative. So, for example, some people in group A will have it, and will therefore be classed as A+ (or A positive). While the ones that don't, are A- (or A negative). And so it goes for groups B, AB and O. The Rhesus (Rh) System

Rh antigens are transmembrane proteins with loops exposed at the surface of red blood cells.

They appear to be used for the transport of carbon dioxide and/or ammonia across the plasma membrane.

They are named for the rhesus monkey in which they were first discovered.

RBCs that are "Rh positive" express the antigen designated D.

85% of the population is RhD positive, the other 15% of the population is running around with RhD negative blood.

The Rhesus (Rh) System (Cont.)

Rh Blood Group and Rh Incompatibility

A person with Rh- blood can develop Rh antibodies in the blood plasma if he or she receives blood from a person with Rh+ blood, whose Rh antigens can trigger the production of Rh antibodies.

A person with Rh+ blood can receive blood from a person with Rh- blood without any problems.

Why is an Rh incompatibility so dangerous when ABO incompatibility is not during pregnancy?

Most anti-A or anti-B antibodies are of the IgM class (large molecules) and these do not cross the placenta.

In fact, an Rh/type O mother carrying an Rh+/type A, B, or AB fetus is resistant to sensitisation to the Rh antigen.

Her anti-A and anti-B antibodies destroy any fetal cells that enter her blood before they can elicit anti-Rh antibodies in her.

This phenomenon has led to an effective preventive measure to avoid Rh sensitisation. Shortly after each birth of an Rh+ baby, the mother is given an injection of anti-Rh antibodies (or Rhogam).

These passively acquired antibodies destroy any foetal cells that got into her circulation before they can elicit an active immune response in her. Rh incompatibility during pregnancy (cont.)

The ABO Blood Group System

Laboratory Determination of the ABO System

Several methods for testing the ABO group of an individual exist. The most common method is:

Serology: This is a direct detection of the ABO antigens. It is the main method used in blood transfusion centres and hospital blood banks.

Thisform of testing involves two components: a) Antibodies that are specific at detecting a particular ABO antigen on RBCs. b) Cells that are of a known ABO group that are agglutinated by the naturally occurring antibodies in the person'sserum.

Illustration of the forward and reverse grouping reaction patterns of the ABO groups using a blood group tile

http://www.bh.rmit.edu.au/mls/subjects/abo/resources/genetics1.htm

When RBCs carrying one or both antigens are exposed to the corresponding antibodies, they agglutinate; that is, clump together. People usually have antibodies against those red cell antigens that they lack.

People with blood group O are called "universal donors" and people with blood group AB are called "universal receivers." Blood transfusions who can receive blood from whom?

There are numerous signs that indicate a transfusion reaction and these can vary from very mild to serious life-threatening situations. If the patient is showing any abnormal clinical signs the surgeon should be informed immediately and the transfusion stopped. The usual treatment of a blood transfusion reaction is to administer crystalloid fluids, antihistamines, antibiotics and corticosteroids.

Clinical signs associated with blood transfusion reaction

Urticaria Hypersalivation Muscle tremorsTachycardiaVomiting/nauseaRestlessnessJaundiceDyspneaHemoglobinuriaPyrexiaFacial edemaTachypneaConvulsions

BLOOD PPRODUCTS FOR TRANSFUSION

WHOLE BLOOD- Not commonly used except for extreme cases of acute hemorrhages. Replaces blood volume and all blood products: RBCs , plasma proteins, Fresh Platelets and other clotting factors.

PACKED RED BLOOD CELLS Use to increase the oxygen- carrying capacity of blood in anemias, surgery and disorders with slow bleeding. Use to one unit of PRBCs has the same amount of oxygen-carrying RBCs as a unit of whole Blood. One unit increases hematocrit by APPROX. 1%-3%.

AUTOLOGOUS RBCSUsed for blood replacement following planned elective surgery. Client donate blood for autologous transfusion 4-5 weeks prior to surgery.

PLATELETReplace platelet to client with bleeding disorders or platelet deficiency. Fresh platelets are most effective. Each unit should increase the average adult platelet by 5000 platelet/microliter.

FRESH FROZEN PLASMAExpands blood volume and provides clotting factor. Does not need to be typed and crossmatched (contained no RBCs)each unit will increase the level of of any clotting factor by 2%to 3% in an average adult

ALBUMIN AND PLASMA PROTEIN FRACTION CLOTTING FACTORS AND CRYOPRECIPITATEBlood expanders, provides plasma proteins, used for clients with clotting factor deficiencies. Each provides different factors involved in the clotting. CLOTTING PATHWAY;CRYOPRECIPITATE ALSO CONTAINS FIBRINOGEN

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