Chapter 14

BLOOD!

I. Function of BloodA. Pick up and delivery system (Federal Express)1. Picks up food and oxygen from the digestive and respiratory systems

2. Delivers them to cells while picking up wastes from cells for delivery to the excretory organs

B. Also functions as the body’s heat regulating mechanism1. Absorbs large quantities

of heat and transfers this heat from the core of body to its surface, where it can be dissipated.

II. Composition of BloodA. Volume of blood1. Females – 4 to 5 liters2. Males – 5 to 6 liters3. One unit of blood is about 0.5 liters

B. Blood components1. Plasma – fluid like portion

made 90% of water and 10% solutes (proteins, electrolytes and antibodies)

2. Formed elementsa. Red blood cellsb. White blood cellsc. Platelets

Composition of Blood

III. Red Blood CellsA. Anatomy1. Normal, mature RBC has no nucleus, mitochondria, or ribosomes

2. Contains hemoglobin – a red pigment which has 4 iron atoms attached. Each RBC has 200-300 million molecules of hemoglobin

3. Depressed in the middle so it has a thinner middle (think of a Jr. mint)a. Unique shape allows it to be flexible as it is forces to pass through deforming passages

B. RBC’s are the most numerous of the cells found in bloodC. Physiology – main function is to transport oxygen and carbon dioxide in the body

D. Lifecycle1. Formed in the bone marrow2. Circulates about 105-120

days, but then becomes fragmented and breaks apart

3. Macrophage cells phagocytose the aged RBC fragments

4. The iron is returned to the bone marrow to make new RBC

Circulation for about120 days

Red blood celldeath andphagocytosis

1

2 Heme

Globin

Biliverdin

3

Aminoacids

Reused forprotein synthesis

4

Aminoacids

Reused forprotein synthesisGlobin

Urine

Stercobilin

Bilirubin

Urobilinogen

Feces

Largeintestine

Smallintestine

Circulation for about120 days

Bacteria

Bilirubin

Red blood celldeath andphagocytosis

Transferrin

Fe3+

Fe3+ Transferrin

Liver

+Globin

+Vitamin B12

+Erythopoietin

Key:in blood

in bile

Erythropoiesis inred bone marrow

Kidney

Macrophage inspleen, liver, orred bone marrow

Ferritin

Urobilin

Heme

Biliverdin Bilirubin

Fe3+

14

13 12

1110

9

8

7

654

3

2

1

Transferrin

IV. White Blood cells

A. Anatomy and Physiology and Lifespan1. All have nuclei and generally larger than RBC

a. Granulocytes (all for acute infection)i. Neutrophils – function for cellular defense – phagocytosis of small microorganisms. Lasts from hours to 3 days.

ii. Eosinophils – functions for cellular defense – phagocytosis of large microorganisms, especially in digestive and respiratory tracts. Lasts 10-12 days

iii. Basophils – functions to secrete heparin (anticoagulant) and histamine. Lasts hours to 3 days.

b. Agranulocytes (all for chronic infection)i. Lymphocytes – functions to secrete antibodies. Lasts days to years

ii. Monocytes – functions to migrate out of blood to enter tissue space as a macrophage and ingesting bacteria, cellular debris and cancerous cells. Lasts months.

B. Formation of WBC1. The granulocytes and a few agranulocytes originate in the red bone marrow

2. Most agranulocytes originate in lymphatic tissue

V. PlateletsA. Function is to help form blood clots called platelet plug which stops the flow of blood in to the tissues.B. Lifespan – Lasts 7 to 10 days

VI. ABO Blood TypesRefers to the type of antigen (A, B, and Rh) located on the surface of the RBC membrane

A. Types1. Type A blood has A

antigen on the RBC2. Type B blood has B

antigen on the RBC3. Type AB blood has both

antigens A and B on the RBC

4. Type O has NEITHER A antigen nor B antigen

B. Two important principles1. A person never has antibodies against their own antigens on their own RBC. If it did the antibody would destroy his own RBC

2. A person does contain the antibodies against the opposite antigen (exception with type AB blood)a. Type A blood contains

antigen A and antibody Bb. Type B blood contains

antigen B and antibody A

c. Type AB blood contains antigens A and B but neither antibody A nor B

d. Type O blood contains neither antigen A or B but does contain antibodies A and B

ABO Blood Groups

C. Giving the person a blood type that does not match will cause agglutination where the blood cells clump

D. Universal donor – Type O because it does not contain antigens A or B so it can be safely given to MOST individuals

E. Transfusion – receiving blood at the time of need. If it is someone else’s blood it’s called homologous transfusion. If it is your own blood, it is called autologous transfusion.

VII. Rh SystemA. Rh + means Rh antigen os present on RBC while Rh – means it is not. (blood test required at marriage)

B. Normally Rh antibodies are not present unless an Rh – person has received Rh + blood. This can happen in two ways

1. If an Rh – person receives a transfusion (can be male or female)

2. If an Rh – woman marries and Rh + man and becomes pregnant with his child. If the baby is Rh + the mother will make antibodies in her blood. The danger comes with the 2nd pregnancy if she has an Rh + baby then her blood will react against the 2nd baby. To stop the mother from making Rh antibodies , an Rh – will will be given a shot of RhoGam….so the possibility of harming the baby is no longer there.

VIII. Blood’s ability to Clot

This is called coagulation.Coagulation can be good or bad

A. Good – if vessel becomes ruptured or cut then the blood needs to thicken and clot at the site1. Injury occurs – step one:

sticky platelets first arrive on the scene to make a platelet plug. This is activated by applying pressure

2. Then fibrin (think threads of tissue) trap RBC’s to form a clot or mesh (“scab”)

B. Bad – if not needed, coagulation must be prevented. You want your blood to flow at a good rate without any clots. Clots can block a particular passage way and cause tissue death (in the heart or brain)

C. Factors that induce coagulation1. Rough spot in vessel

lining – such as build up of plaques of cholesterol-lipid material

2. Slow blood flow – as in body immobility – as in patients who are bed ridden. Physicians insist that bed patients be moved frequently.

3. Heparin is given to thin the blood and keep clots from forming. Some older people take an asprin a day to keep the blood from forming clots (Bayer commercial)

4. Other drugs have been used to dissolve clots. If stroke victim is given a clot dissolving drug within 6 hours then it can often improve the serious after affects of the stroke.

IX. Conditions of the Blood

A. AnemiaLow RBC countTherefore deficiency in hemoglobin which carries the oxygen molecules to the cells and therefore the patient experiences fatigue

B. LeukopeniaA decrease WBC count such as in AIDSLower WBC decreases their immune system (Acquired Immune Deficiency Syndrome) so they are not able to fight off common illnesses

C. LeukocytosisAn increase in WBC countPatient will have elevated WBC count when fighting a bacterial infectionOne of the key symptoms is appendicitis

D. Erythroblastosis fetalis

Rh positive fetus that is carried by Rh negative mother that has built antibodies against the babies blood

E. LeukemiaMalignant condition of the bloodFive different types in which there is leukocytosis and anemia

F. HemophiliaThis was a common illness in the Royal family….beginning with Czar Nicholas and his sonPatient is unable to clot blood and theu can bleed to death from very minor injuries

G. ThrombosisClot the stays put in the same place it forms

H. EmbolismA clot that becomes dislodged and travels the circulatory systemThis is what a clot is harmful, if it gets lodged and blocks blood, especially in the brain or heart

I. Hypovolemic Shock

Hypo– low, vol- volume, emic- bloodPerson suffering from losing large amounts of blood.

Results in 4 things:

1. Causes heart to race to try to pump blood that is not there (common sign right before death)2. The blood pressure drops causing collapse or fainting

3. Kidneys stop producing UA to conserve the volume of blood that is left4. Person becomes very thirsty as the blood craves fluids to replace the lost blood volume

The last hours of Christ:

Medical experts believe that Jesus was in hypovolemic shock from the Roman flogging that occurred before his death

First of all hematidrosis (blood sweat) leaves your skin in a very fragile condition..

Floggings in those days were braided leather whips with metal ball, chipped bone and stones interwoven

The beatings were from the shoulders to the buttocks and down the hamstrings. The bone chips and metal would grip the skin and tear as it went down the back

Historians of that day report that often the veins, muscles, and bowels if the victim were often open and exposed

So most assuredly Jesus lost a tremendous amount of blood during this time

READ Luke 23:26Jesus goes into the 2nd part of hypovolemic shock and collapses, unable to carry the cross

READ John 19:28Here is part 4 of the shock…..He experiences excessive thirst