*** A&p Ch. 19 Blood

Front 1

What is blood?

Back 1

Blood is the life-sustaining transport vehicle of the cardiovascular system. A liquid connective tissue consisting of cells & extrac. matrix.

- plasma

- formed elements

Front 2

What is hematology?

Back 2

The study of blood. Adults have 4-6L of blood (~1.5 gallons)

Front 3

What does the circulatory system consist of?

Back 3

The heart, blood vessels & blood

Front 4

What are the functions of blood?

Back 4

1. Transport: O2, CO2, nutrients, wastes, hormones, & stem cells.

2. Protection: inflammation, limit spread of infection, destroy microorganisms & cancer cells, neutralize toxins, & initiates clotting.

3. Regulation: fluid balance, stabilizes PH, & temperature control. Maintain adequate fluis volume in circulatory system.

Front 5

What is the normal range of blood volume in a healthy person?

Back 5

Females: 4-5 L

Males: 5-6 L

Front 6

What's the normal PH of blood?

Back 6

7.35 - 7.45

Front 7

What percentage of blood makes up body weight?

Back 7

~8%

Front 8

What percentage of blood plasma is water?

Back 8

~90%

Front 9

What are the 2 main components of blood?

Back 9

Plasma (55%) matrix of blood. Clear, light yellow fluid consisting of proteins, clotting factors & water. Serum= plasma without clotting factors.

Formed elements (45%) blood cells & cell fragments. Include

- erythrocytes (RBCs) majority

- leukocytes (WBCs) <1%

- platelets

Front 10

List the plasma proteins and functions of each, in 1st component of blood- plasma

Back 10

Albumin: 58% of plasma proteins. Helps maintain osmotic pressure, main hydrophobic carrier.

Globulins: 38% of plasma proteins. Immunity: antibodies, transport: bind to molecules such as hormones., clotting factors.

Fibrinogen: 4% of plasma proteins. Converted to fibrin during clot formation.

Other substances: 2%

- ions: (electrolytes): sodium, potassium, calcium, chloride, bicarbonate.

- nutrients: glucose, carbohydrates, amino acids.

- waste products: lactic acid, urea, creatine.

- respiratory gases: O2 & carbon dioxide.

Front 11

What are the properties of blood?

Back 11

Viscosity: resistance of a fluid to flow, "friction of fluid". Whole blood is 4.5-5.5x as viscous as water.

Osmolarity: total molarity of those dissolved particles that cannot pass through the blood vessel wall. If too high, blood absorbs too much water, increasing BP. If too low, too much water stays in tissue, BP drops & edema occurs (condition characterized by an excess of watery fluid collecting in the cavities or tissues of the body).

Front 12

List the main functions of the formed elements

Back 12

Erythrocytes: GAS transport! Each RBC has HEMAGLOBIN, transport & exchange of CO2.

Leukocytes: defense against disease

Platelets: function in clotting by 2 mechanisms: formation of platelet plugs, formation of clots

Front 13

Define hemoglobin and list its structure

Back 13

Hemoglobin: is a red protein responsible for transporting oxygen in blood. Its molecule comprises four subunits, each containing an iron atom bound to a heme group.

Men= 13-18g/dl, women= 12-16g/dl

- produces carbonic anhydrase which breaks down CO2 into carbonic acid, important for PH balance.

- once RBC contains 250 million Hb groups thus it can carry 1 billion molecules of O2.

Structure:

Each Hemoglobin molecule consists of:

4 heme & 4 globin molecules.

Heme groups: transport O2, binds O2 to Iron at its center.

Globins: transport carbon dioxide & nitric oxide. protein chains, 2 alpha & 2 beta chains.

Front 14

Define hematocrit

Back 14

Hematocrit: % of whole blood that is RBCs. Men= 42-52% cells, women= 37-48% cells.

Front 15

What is hematopoiesis? What is erythropoiesis?

Back 15

Hematopoiesis: the production of blood cells and platelets, which occurs in the bone marrow.

Erythropoiesis: process of formation of RBCs (takes about 15 days)

Front 16

Describe erythrocytes

Back 16

Erythrocytes: RBCs are small diameter, disc shaped with thick rim. Lack mitochondria or DNA. Blood type determined by surface proteins. Are ANUCLEATE so cannot synthesize new proteins, grow or divide. Macrophages in spleen engulf & breakdown dying RBCs.

- transport & exchange of CO2. Carbon dioxide diffuses into RBCs & combines with water to form carbonic acid which quickly dissolves into hydrogen ion & bicarbonate ion.

- carbonic anhydrase reversibly catalyzes the conversion of carbon dioxide & water to carbonic acid.

Front 17

Explain erythrocyte production

Back 17

Erythrocyte production: erythropoiesis:

Average lifespan of about 120 days. Reduction in cell size, increase in cell number, synthesis of hemoglobin & loss of nucleus. Erythroblasts multiply & synthesize hemaglobin.

Front 18

List the stages of erythropoiesis

Back 18

Stages of transformations:

Stem cell- CFU- precursor- mature cell.

1. Hematopoietic stem cell: transforms into myeloid stem cell.

2. Myeloid stem cell: transforms into proerythroblast.

3. Proerythroblast: divides many times, transforming into basophilic erythroblasts.

4. Basophilic erythroblasts: synthesize many ribosomes, which stain blue.

5. Polychromatic erythroblasts: synthesize large amounts of red-hued hemoglobin;cell now shows both pink and blue areas.

6. Orthochromatic erythroblasts: contain mostly hemoglobin, so appear just pink; eject most organelles; nucleus degrades, causing concave shape.

7. Reticulocytes: still contain small amount of ribosomes.

8. Mature erythrocyte: in 2 days, ribosomes degrade, transforming into mature RBC.

- reticulocyte count indicates rate of RBC formation

Front 19

Nutritional needs for RBC formation:

Back 19

Too few RBCs lead to tissue hypoxia, too many increase blood viscosity.

- >2 million RBCs made per second.

Balance between RBC production & destruction depends on:

- hormonal controls

- dietary requirements:

... IRON

... VITAMIN B12 & FOLIC ACID

... VITAMIN C

Front 20

Requirements for RBC formation:

Back 20

Hormonal control:

Erythropoietin (EPO): hormone that stimulates formation of RBCs.

- Releases by kidneys in response to hypoxia. HIF can accumulate, which triggers synthesis of EPO.

Causes of hypoxia: decreased RBC numbers due to hemorrhage or increased destruction. Insufficient hemoglobin per RBC. Reduced availability of O2.

Too many erythrocytes or high O2 levels in blood inhibit EPO production.

- EPO causes erythrocytes to mature faster. Testosterone enhances EPO production, resulting in higher RBC counts in males.

Front 21

Erythrocyte homeostasis:

Back 21

- negative feedback control

Drop in RBC count causes kidney hypoxia. Kidney production of erythropoietin stimulates bone marrow.

- stimuli for increasing erythropoiesis:

Low levels o2 (hypoxia)

High altitude

Increase in exercise

- artificial EPO increases hematocrit which allows athletes to increase stamina and performance. Blood becomes like sludge and can cause clotting, stroke or heart failure.

Front 22

Fate and destruction of RBCs

Back 22

RBC breakdown: heme, iron, and globin are separated.

Iron is stored for resuse.

Heme is degraded to yellow pigment bilirubin. Liver secretes bilirubin (in bile) into intestines, where it is degraded to pigment urobilinogen. Urobilinogen is transformed into brown pigment stercobilin that leaves body in feces.

Globin is metabolized into amino acids, released into circulation.

Front 23

List the disorders of blood - erythrocyte (RBCs)

Back 23

Most erythrocyte disorders are classified as anemia or polycythemia.

Anemia: decrease in number of RBCs or hemoglobin causing blood to have abnormally low O2 carrying capacity. Hematocrit is low, person may be tired or have blue coloring. Not enough iron or vit. B12. Loss of large quantity of blood. Body not producing enough RBCs.

Symptoms: fatigue, pallor, dyspnea, and chills.

Three groups based on cause:

BLOOD LOSS:

hemorrhagic anemia- rapid blood loss, treated by blood replacement.

Chronic hemorrhagic anemia: slight but persistent blood loss. Hemorrhoids.

NOT ENOUGH RBC production:

Iron deficiency anemia: RBCs produced are called microcytes (can't synthesize hemoglobin due to lack of iron)

Treatment: iron supplements

factor (absorbs Vit.B12, helps RBCs divide). If they cant divide, they result in large macrocytes.

Treatment: B12 injections

Renal anemia: (lack of EPO)

Treatment: synthetic EPO

Aplastic anemia: destruction or inhibition of red bone marrow. All formsled elements are effected. By drugs, chemicals, radiation or viruses.

Treatment: transfusions, transplanted stem cells.

Pernicious anemia: (vegetarians) autoimmune disease destroys stomach mucosa that produces intrinsic factor (absorbs Vit.B12, helps RBCs divide). If they cant divide, they result in large macrocytes. Treatment: B12 injections Renal anemia: (lack of EPO) Treatment: synthetic EPOAplastic anemia: destruction or inhibition of red bone marrow. All formsled elements are effected. By drugs, chemicals, radiation or viruses. Treatment: transfusions, transplanted stem cells. TOO MANY RBCS DESTROYED: (Lysis of RBCs, heolmolytic anemias). Caused by incompatible transfusions or infections, or hemoglobin abnormalities. Thalassemias: one globin chain is absent or faulty. Single amino acid change in beta chain of hemoglobin, looks like a C. Sickle-cell anemia: hemoglobin S: mutated. Possible benefit: people with sickle cell can not contract malaria. Treatment: transfusions, inhaled nitric oxide.

TOO MANY RBCS DESTROYED: (

(Lysis of RBCs, heolmolytic anemias). Caused by incompatible transfusions or infections, or hemoglobin abnormalities.

Thalassemias: one globin chain is absent or faulty. Single amino acid change in beta chain of hemoglobin, looks like a C.

Sickle-cell anemia: hemoglobin S: mutated. Possible benefit: people with sickle cell can not contract malaria.

Treatment: transfusions, inhaled nitric oxide.

Polycythemia: abnormally excess of RBCs. Increases blood viscosity, pressure and clotting which may lead to heart attack.

- polycemia vera: bone marrow cancer leads to excess RBCs. Hematoct may go as high as 80%. Treatment: therapeutic phlebotomy.

- secondary polycythemia: cause by low O2 levels (high altitude) or increased EPO production.

- blood doping

Sickle cell disease/anemia: genetically abnormal RBCs, abnormal hemoglobin.

Jaundice: yellowing of skin that occurs when TOO MUCH BILIRUBIN is present in blood.

Front 24

Erythrocyte disorders:

Back 24

Most erythrocyte disorders are classified as anemia or polycythemia.

Anemia: blood has abnormally low O2 carrying capacity that is too low to support normal metabolism.

Symptoms: fatigue, pallor, dyspnea, and chills.

Three groups based on cause:

Blood loss, not enough RBCs produced or too many RBCS being destroyed.

- blood loss:

hemorrhagic anemia- rapid blood loss, treated by blood replacement.

Chronic hemorrhagic anemia: slight but persistent blood loss. Hemorrhoids.

Front 25

What is leukocytosis?

Back 25

WBC count over 11,000/mm3.

Normal increase in response to infection. Abnormal if >11k is persisting (leukemia, aids)

Front 26

What are the 2 categories for leukocytes?

Back 26

Granulocytes: visible cytoplasmic granules. These are:

- NEUTROPHILS, EOSINOPHILS & BASOPHILS.

Larger but shorter lived that RBCs.

Contain lobed, rather than circular nuclei.

Agranulocytes: no visible cytoplasmic granules. These are:

LYMPHOCYTES & MONOCYTES.

Have spherical or kidney shaped nuclei. By decreasing abundance in blood: Never let monkeys eat bananas.

Front 27

Describe the 1st category of leukocytes

Back 27

GRANULOCYTES:

Neutrophils: most numerous WBC, about twice the size of RBCs and contain defensins: granules merge with phagosome to form "spears" that peirce holes in membrane of ingested microbe. Are called the "bacterial slayers", very phagocytic, kill microbes by respiratory burst: cell synthesizes potent oxidizing substances (bleach or hydrogen peroxide).

Eosinophils: account for 2-4% of all WBCs, resemble ear muff shape. Contain digestive enzymes and release them on large parasitic worms, digesting their surface. Also play a role in allergies and asthma as well as immune response modulators.

Basophils: rarest WBC, 0.5-1%. Granules contain HISTAMINE: inflammatory chemical that acts as vasodilator & attracts WBCs to inflamed sites. Functionally similar to mast cells.

Front 28

List the functions of GRANULOCYTES - which is the 1st category of leukocytes

Back 28

Neutrophils: bacterial slayers.

Eosinophils: reduce allergic reactions & fight worms (parasitic infections).

Basophils: secretes:

HISTAMINE: vasodilator, speeds flood of blood into injured areas.

HEPARIN: anticoagulant, promotes mobility of other WBCs in the area.

Front 29

Describe the 2nd category of leukocytes

Back 29

AGRANULOCYTES:

Lymphocytes: 25% of WBCs, mostly found in lymphoid tissue (lymph nodes, spleen), and few circulate in blood. CRUCIAL TO IMMUNITY.

2 types:

- T lymphocytes (T cells): act against virus infected cells & tumor cells.

- B lymphocytes (B cells): give rise to plasma cells, which produce antibodies.

Monocytes: 3-8% of WBCS, largest WBC, U or kidney shaped nuclei.

*** leave circulation, enter tissue & differentiate into macrophages.

Activately phagocytic cells; crucial against viruses, intrac. bacterial parasites & chronic infections.

Activate lymphocytes to mount an immune response.

Front 30

List the functions of AGRANULOCYTES - which is the 2nd category of leukocytes

Back 30

Lymphocytes: immune responses, crucial to immunity.

T cells & B cells (specific immunity)

Destroy cells (cancer, foreign & virally infected)

Monocytes: aid in viral infections & inflammation.

Leave bloodstream & transform into macrophages.

Phagocytize pathogens & debris.

Front 31

What is leukopoiesis?

Back 31

Leukopoiesis: the production of WBCs.

Stimulated by 2 types of chemical messengers from red bone marrow & mature WBCs:

- INTERLEUKINS: ex. IL-3, IL-5

- COLONY STIMULATING FACTORS (CSFs): named for WBC cell type they stimulate.

All leukocytes originate from hemocytoblasts stem cell that branches into 2 pathways:

1. lymphoid stem cells produces lymphocytes.

2. myeloid stem cells produce all other elements.

Front 32

Explain Granolocyte production (1 of 2 leukocytes categories)

Back 32

1. Myeloblasts: arise from myeloid line stem cells.

2. Promyelocytes: accumulate lysosomes.

3. Myelocytes: accumulate granules.

4. Band cells: nuclei from curved arc.

5. Mature granulocyte: nuclei become segmented before being released in blood. 10x more are stored in bone marrow than in blood. 3x more WBCs are formed that RBCs; WBCs have a shorter life (die by fighting microbes)

- granulocytes are stored in bone marrow

Front 33

Explain Agranolocyte production (2 of 2 leukocytes categories)

Back 33

- monocytes: derived from myeloid line, can live for several months. monoblast to

promonocyte to

monocyte.

- lymphocytes: derived from lymphoid line, live from a few hours to decades.

- T LYMPHOCYTE PRECURSORS: give rise to immature T lymphocytes that mature in thymus.

- B LYMPHOCYTE PRECURSORS: give rise to immature B lymphocytes that mature in bone marrow.

- lymphoid stem cells to lymphocytes

- myeloid stem cells to all others

Front 34

List the disorders of WBCs

Back 34

Leukopenia: low WBC count <5000/ul, Causes: radiation, poisons, infectious disease, drugs

Effects: elevated risk of infection

Leukocytosis: high WBC count above 10,000/ul,

Causes: infection, allergy & disease

Differential WBC count: identifies what % of the total WBC count consist of each type of leukocyte.

Infectious mononucleosis: overproduction of abnormal WBC, highlt contagious viral infection (kissing disease) which elevates number of agranulocytes and enlarged lymphocytes in the blood. Caused by Epstein-Barr virus.

Symptoms: tired, achy, chronic sore throat, low fever. 4-6 weeks.

Leukemia: overproduction of abnormal WBC, cancer of blood forming cells in bone marrow. Cant fight infection, invade and destroy native tissues, treatments include bone marrow transplant, irradiation, antileukemic drugs, stem cell transplants and without treatment, its fatal.

Types of leukemia:

- myeloid leukemia: involves myeloblast

- lymphocytic leukemia: involves lymphocytes

- acute leukemia: (quickly advancing) derives from stem cells, primarily affecting children

- chronic leukemia: (slowly advancing) proliferation of later cell stages, more prevalent in old people.

Front 35

Explain platelets (the 3rd formed element in blood)

Back 35

Platelets/thrombocytes: fragments of megakaryocytes, normal count: 150,000-400,000/ml.

- Function in CLOTTING by 2 mechanisms:

1. Formation of platelet plugs

2. Formation of clots

- their granules contain ADP, serotonin, PDGF & thromboxanes

Front 36

What is a Pluripotent stem cell?

Back 36

Aka hemocytoblasts stem cells are master cells. They can potentially produce any cell or tissue the body needs to repair itself. This “master” property is called pluripotency.

All the formed elements are derived from hemocytoblasts. Are located in bone marrow.

- when hemocytoblast divides, it forms either a myeloid cell or a lymphoid cell. - stem cell then branches into 2 pathways:

- lymphoid stem cells produces lymphocytes

- myeloid stem cells produce all other elements

Front 37

What is a reticulocyte?

Back 37

In erythrocyte production and erythropoiesis, Reticulocytes are immature red blood cells (cells that aren't yet fully developed). A reticulocyte count measures: the number of reticulocytes in the blood. This helps doctors see how many new red blood cells the bone marrow is making.

Front 38

What is erythropoietin?

Back 38

Hormonal control in RBC formation:

Erythropoietin: (EPO) is a hormone that stimulates formation of RBCs. Mechanism for regulating erythropoiesis. Kidney production of EPO stimulates bone marrow

Front 39

Define hypoxia, what dont sherpas suffer from hypoxia and why do athletes train in high elevation cities?

Back 39

Hypoxia: an absence of enough oxygen in the tissues to sustain bodily functions. Few RBCs. Sherpa people have lived in the high elevation for their entire life. Their blood has adjusted to the high elevation while the people they guide are usually living in places of low elevation or sea level.

Athletes train in high elevation because the air is "thinner" at high altitudes meaning there are fewer oxygen molecules per volume of air. Every breath taken at a high altitude delivers less of what working muscles require. By training at high altitudes, athletes aim to allow their bodies to produce extra red blood cells.

Front 40

What happens to old RBCs?

Back 40

As red blood cells get old, macrophages in the spleen engulf and break them down. This happens whether the red blood cell is damaged or not. ... Most importantly it tries to recycle the hemoglobin, which is the most important part of the cell - it is the chemical that allows the cell to carry oxygen around the body.

Front 41

What happens to old RBCs?

Back 41

As red blood cells get old, macrophages in the spleen engulf and break them down. This happens whether the red blood cell is damaged or not. ... Most importantly it tries to recycle the hemoglobin, which is the most important part of the cell - it is the chemical that allows the cell to carry oxygen around the body.

Front 42

List again the functions of all formed elements

Back 42

Erythrocytes (RBC): transport oxygen and carbon dioxide

Leukocytes (WBC): 5 types

GRANULOCYTES:

- neutrophils: phagocytize ls microorganisms and other substances

- eosinophils: attack certain worm parasites, releases chemicals that modulate inflammation, negatively impacts airways during asthma attacks

- basophils: releases histamine to promote inflammation and heparin to prevent clot formation.

AGRANULOCYTES:

- lymphocyte: produces antibodies & other chemicals responsible for destroying microorganisms, contributes to allergic reactions, graft rejection, tumor control, & regulation of the immune system.

- monocyte: phagocytic cell in the blood, leaves the blood & becomes a macrophage, which phagocytizes bacteria, dead cells, cell fragments, & other debris within tissues.

Platelets: forms platelet plugs, release chemicals necessary for blood clotting

Front 43

Give the description for all formed elements

Back 43

Erythrocytes (RBC): biconcave disc, no nucleus, contains hemoglobin, which colors the cell red, 7.5 in diameter Leukocytes (WBC): 5 types,

spherical cells with a nucleus GRANULOCYTES: - neutrophils: nucleus with 2-5 lobes connected by thin filaments, cytoplasmic granules stain a light pink or reddish purple, 10-12 diameter.- eosinophils: nucleus often bilobed, cytoplasmic granules stain orange red or bright red, 11-14 diameter - basophils: nucleus with two indistinct lobes, cytoplasmic granules stain blue purple, 10-12 diameter AGRANULOCYTES: - lymphocyte: round nucleus, cytoplasm forms a thin ring around the nucleus, 6-14 diameter - monocyte: nucleus round, kidney shaped or horseshoe shaped, contains more cytoplasm than lymphocyte does, 12-20 diameter Platelets: cell fragment surrounded by plasma membrane & containing granules, 2-4 diameter

Front 44

Break down in simple terms the formes elements

Back 44

Erythrocytes (RBC):

Leukocytes (WBC): 5 types GRANULOCYTES:

- neutrophils:

- eosinophils:

- basophils:

AGRANULOCYTES:

- lymphocyte:

- monocyte:

Platelets:

Front 45

Describe the life cycle of a RBC, including formation, lifespan and destruction

Back 45

1. Low O2, levels in blood stimulate kidneys to produce erythropoietin.

2. Erythropoietin levels rise in blood.

3. Erythropoietin & necessary raw materials in blood promote erythropoiesis in red bone marrow.

4. New erythrocytes enter bloodstream; function about 120 days.

5. Aged & damaged red blood cells are engulfed by macrophages of spleen, liver & bone marrow. The hemoglobin is broken down.

6. Raw materials are made available in blood for erythrocyte synthesis

Front 46

Define antigen and antibody

Back 46

Antigen: anything perceived as foreign that can generate an immune response/the production of antibodies. Antibody: also known as an immunoglobulin, is a large, Y-shaped blood protein produced mainly by plasma cells thats produced in response to a specific antigen. It is used by the immune system to neutralize pathogens such as pathogenic bacteria and viruses. ... Their production is the main function of the humoral immune system.

Front 47

Define agglutination

Back 47

Agglutination: is the clumping of particles and is the process that occurs if an antigen is mixed with its corresponding antibody called isoagglutinin. This term is commonly used in blood grouping. Agglutinogens (RBC antigens): promote agglutination

Front 48

Define HDN

Back 48

Hemolytic disease of the newborn (HDN): is a blood problem in newborn babies. It occurs when your baby's red blood cells break down at a fast rate. It's also called erythroblastosis fetalis.-HDN occurs when the immune system of the mother sees a baby's red blood cells as foreign. Antibodies then develop against the baby's red blood cells. These antibodies attack the red blood cells in the baby's blood and cause them to break down too early.

Front 49

Define Rh factor

Back 49

Rh factor: (C,D,E) is a blood protein discovered in rhesus monkey. People without Rh factor are known as Rh negative, while people with the Rh factor are Rh positive. - If a woman who is Rh negative is pregnant with a fetus who is Rh positive, her body will make antibodies against the fetus's blood.- Rh D most reactive (D antigen-agglutinations) on RBCs considered Rh+.