Chapter 12: Blood

what is blood composed of?

1. plasma


1. plasam proteins
2. other solutes
3. water
2. cellular elements


1. platelets
2. leukocytes (WBC)
3. erythrocytes (RBC)

what is the function of plasma?

temperature buffer and transporter

what is plasma composed of?

* 1/4 of extracellular fluid
* 92% water
* 7% plasma proteins
* albumin: π_C carriers
* globulins: carriers, enzymes, hormones, immunoglobulins (transferrin - Fe2+ transport), and fibrinogen/clotting factors
* 1% organic molecules, ions, vitamins, minerals, and dissolved gases

what are erythrocytes?

red blood cells that transport O2, CO2, and H+

what are leukocytes?

white blood cells such as neutrophils, lymphocytes, monocytes, eosinophils, and basophils

what are phagocytes?

leukocytes such as neutrophils, monocytes (in blood), and macrophages (in tissues)

what are immunocytes?

lymphocytes

what are the secretary leukocytes?

basophils (in blood), mast cells (in tissue), and eosinophils

what are thrombocytes?

platelets for coagulation or clotting

what is hemopoiesis?

**active in red bone marrow** within trabecular bone (flat bones, proximal epiphyses of long bones)

→ **recruitment:** inactive yellow bone marrow

→ **production ratio:** 25% RBC; 75% WBC

→ **multipotential:** myeloid progenitor vs lymphoid progenitor

what is erythropoiesis?

* RBC life span \~ 120 days
* developed from myeloid stem cell

how is erythropoiesis stimulated

erythropoietin (EPO)

→ a glycoprotein hormone/cytokine produced by the kidneys and liver

how is erythropoietin (EPO) regulated

\
by hypoxia which produces a response to decreased O2 delivery to the kidneys

what is blood doping?

artificially induced polycythemia has been the subject of numerous athletic scandals

how is blood doping performed

taking testosterone and EPO supplements, or by injecting highly concentrated “packed” red blood cell suspensions

what is the benefit of blood doping

performance advantage due to an increased O2 carrying capacity

what is leukopoiesis?

* WBC life span \~ 120 days
* developed from myeloid stem cells

what is thrombopoiesis?

* developed from myeloid stem cells
* situation where megakaryocytes turn into platelets
* thrombopoietin (TPO) in liver and kidney

what are characteristics of thrombopoiesis

platelets are cell fragments that have a membrane sac containing proteins, enzymes, actin and myosin

what are characteristics of RBC?

* biconcave disc
* cytoskeleton filaments attach to transmembrane proteins which can change shape (crenation, swelling, folding
* can fit through a capillary

by increasing RBC membrane surface, ___

it INCREASES diffusion

what is sickle cell anemia?

blood cells that contain abnormal hemoglobin causing it to change shape (crescent)

what does a RBC consist of?

* no organelles, mitochondria, DNA or ribosomes (NO protein synthesis)
* filled with hemoglobin

how does a RBC produce energy if it does not have mitochondria?

utilizes glycolysis for ATP production

what is the structure of hemoglobin?

* quaternary structure is tetrameric
* globulin contains four chains
* alpha, beta, delta, and fetal gamma
* heme groups
* porphyrin ring with 1 Fe2+
* each Fe2+ holds one O2
* has oxygen carrying capacity

what isoforms of globin do **adults** have?

* **mostly** 2 alpha and 2 beta chains (HbA)
* some 2 alpha and 2 delta chains (HbA2)

what isoforms of globin do **infants** have?

2 alpha and 2 gamma chains

what is the oxygen carrying capacity of a hemoglobin?

* 4 oxygens
* 1.34 mL O2/g Hb
* 1.34 mL O2/g Hb x 15 g Hb/dL whole blood = 20.1 mL O2/dL whole blood

how is hemoglobin processed?

1. RBC hemolysis by macrophages in the spleen, liver, and red marrow
2. recycle globin and Fe2+
3. excrete heme metabolites

how is globin recycled?

globin → amino acid → globin

how is Fe2+ recycled?

\
ferritin, transferrin, and new Fe2+ from diet

what is ferritin

iron storage protein in the liver

what is transferrin

iron transport protein

true/false: Fe2+ is produced by the body

false, the body can only store Fe2+

how is heme metabolites excreted?

* heme → biliverdin → bilirubin
* increased levels of bilirubin = jaundice
* urobilin in urine
* stercobilin in feces

what are the blood group surface antigens?

* agglutinogens
* antigen H (O)
* antigen D (Rh factor)

what is antigen H (O)?

erythrocytes and platelets

→ antigen A and B are directly on RBCs

→ **tells you the blood type**

what is antigen D (Rh factor)

erythrocytes

→ sensitization

→ **tells you whether the blood type is positive or negative**

what are circulating antibodies?

agglutinins

→ antibody a, b, and d

if you have the antigen, ______________

you do not produce that antibody because you would be **fighting against** yourself

if you DO NOT have the antigen, ______________

you produce that antibody to **protect** yourself from foreign substances

blood type A has ______ antibodies and ______ antigens

B; A

blood type B has ______ antibodies and ______ antigens

A; B

blood type AB has ______ antibodies and ______ antigens

no; A and B

blood type O has ______ antibodies and ______ antigens

A and B; no

what is agglutination?

antibodies confide in antigen resulting in a clump

→ when blood sample clumps, it means that the antigen and antibody is present

agglutination in blood type A+ results in _________________

* antibody A and antigen A that cause clumping
* antibody D that cause clumping (+)

agglutination in blood type B+ results in _________________

* antibody B and antigen B that cause clumping
* antibody D that cause clumping (+)

agglutination in blood type AB+ results in _________________

* antibody A and antigen A that cause clumping
* antibody B and antigen B that cause clumping
* antibody D that cause clumping (+)

agglutination in blood type O- results in _________________

* no antibodies or antigens that cause clumping
* no antibody D that cause clumping (-)

what is major agglutination?

recipient of blood antibodies react with donor blood antigens

what would happen if you gave a person with type O- blood a transfusion of type A+ blood

major agglutination would occur because the recipient (Type O-) has antibodies that will fight donor (Type A+) antigens

what is minor agglutination?

donor blood antibodies react with recipient blood antigens

what would happen if you gave a person with type A+ blood a transfusion of type O- blood?

minor agglutination would occur, but not enough to worry about

what is whole blood?

giving RBCs with antigens on surface

what is plasma or serum?

serum has clotting factors that are removed; there is no need to worry about antigens or major agglutination in both

what is a hemocytometer?

a method to count RBCs

→ females: 3.9-5.6 million per microliter

→ males: 4.5-6.5 million per microliter due to increased testosterone present

what is erythropenia?

deficiency of RBCs

what is relative polycythemia?

* usually result of dehydration
* INCREASE concentration of RBCs but normal total count and total mass
* LOW plasma volume

what is erythema (polycythemia vera)?

* **high** RBC and WBC counts
* **high** hematocrit
* NO hypoxia (have not experienced lack of O2 in RBCs)
* irrespective of the concentration of erythropoietin → may be increased, decreased, or normal

what is secondary or compensatory polycythemia?

* **high** RBC count
* arterial hypoxia (low delivery of O2 to RBCs which increases RBC count)
* pregnancy can also cause this

what is a hematocrit diagnostic test?

utilizes a centrifuge to determine packed cell volume (plasma, buffy coat, packed RBCs)

→ females: 42% +/- 5

→ males: 47 +/- 7

what hematocrit (HCT) is normal?

HCT A = 50% RBC

males have a higher ratio of total volume to RBC

what is the value for hematocrit (HCT) B?

64% = high polycythemiaa

what is the mean corpuscular volume (MCV)?

* (HCT ratio x 1,000)/**5.5 million per microliter**
* normal value: 87 +/- 5 fL

mean corpuscular volume (MCV) can be used to identify the % volume of packed red blood cells in a sample of whole blood. what are the different sizes of RBCs?

* normocytic = normal
* microcytic = small
* macrocytic = large

when mean corpuscular volume (MCV) is _______, the hematocrit (HCT) is _______

high; high

what is a hemoglobin diagnostic test?

amounts vary depending on counting method

→ females: 12-16 g/dL

→ males: 14-17 g/dL

→ birth: 24 g/dL due to O2 from mom, rapid cell division, breathing, and practicing using muscles

what are the different colors that mean corpuscular hemoglobin (MCH) determine?

* normochromic → normal color
* hyperchromic → darker color due to high ratio of hemoglobin and RBC volume
* hypochromic: → lighter color due to Hb Fe2+ deficit

what are anemias?

* less than 12 g Hb/dL in females and 14 g Hb/dL in males
* O2 carrying capacity is less than 16-19 mL O2/dL whole blood

what is iron deficiency anemia?

* hypochromic cells (lighter color than normal)
* microcytic anemia (mean corpuscular volume is less than 80 fL)

what is thalassemia?

* DECREASE **Hb production** (small Hb)
* genetic risk factors
* microcytic anemia (mean corpuscular volume is less than 80 fL)

what is hemolytic anemia?

* cells burst
* can be genetic such as sickle cell disease which is abnormal HbS

what is pernicious anemia?

* DECREASE **RBC production**
* LACK intrinsic factor, which is needed to absorb B12
* macrocytic anemia (mean corpuscular volume is greater than 100 fL)

what is folic acid and B12 anemia?

* DECREASE **RBC** **production**
* intrinsic factors PRESENT but LACK vitamin B12
* macrocytic anemia (mean corpuscular volume is greater than 100 fL)

what is hemorrhagic anemia?

blood loss

what is aplastic anemia?

* DECREASE RBC production
* due to fault marrow, radiation, poisons, and toxins

what is the lifespan of WBCs?

* varies from hours to years
* constant production of WBCs

what do WBCs look like?

* cytoplasmic granules → granulocytes and agranulocytes
* nuclear shape → polymorphonuclear

what is the immune function of **neutrophils**?

hydrolytic enzymes

what is the immune function of **lymphocytes**?

antibody production

what is the immune function of **monocytes (macrophages)**?

phagocytes and activation of some lymphocytes

what is the immune function of **eosinophils**?

parasites and inflammation regulation

what is the immune function of **basophils**?

inflammation regulation such as allergy responses

what diagnostic test looks at total WBC count?

hemocytometer

what is the total WBC count for females and males?

4,000-11,000 cells/microliter of whole blood

leukocyto**penia**

too few WBCs

leuko**cytosis**

too many WBCs

what are the percentages of WBCs?

* neutrophils: 50-70%
* lymphocytes: 20-40%
* monocytes: 2-8%
* eosinophils: 1-4%
* basophils: 0.1-1%

why is leukocytopenia usually neutropenia?

neutrophils are the most common. if the number drops, it’ll make a difference

what are the different types of leukocytosis?

* neutrophilia
* eosinophilia
* basophilia
* monocytosis
* lymphocytosis

what type of diagnostic test looks at platelet count?

hematocrit

→ females and males: 1.5x10^5 - 4.5x10^5 per microliter of whole blood

what is thromocyto**penia**?

LOW thrombocyte count

→ risk factors

* pregnancy - mild
* idiopathic thromocytopenic purpura (IPT): immune system destruction
* autoimmune diseases: lupus, rheumatoid arthritis
* bacteria in the blood

what is thrrombocytosis?

HIGH thrombocyte count

→ **primarily** due to genetics and faulty stem cells in marrow

→ **secondary** risk factors: cancer, anemia, and blood loss

what does a complete blood count diagnostic test consist of?

* **WBC, RBC**: number per volume of blood analyzed
* **HGB**: mass of Hb found per volume analyzed
* **HCT**: hematocrit
* **MCV**: mean corpuscular volume approximates the size of a typical RBC
* **MCH**: mean cell Hb looks at the average amount within each RBC
* **MCHC**: mean corpuscular Hb concentration looks at the amount of Hb in a packed volume of cells
* **RDW**: RBC distribution width approximates fluctuation in MCV from cell to cell
* **PLT**: number of platelets per volume blood analyzed

what is hemostasis?

**stopping blood** loss via platelet activation that initiates processes localized to an injured vessel

what is the platelet activation process?

1. vascular spasm causes vasoconstriction
2. platelet plug fills damaged space
3. coagulation causes activation of proteins to result in clotting
4. clot retraction
5. process is completed with firbinolysis (break down of fibrin) and tissue repair

what happens during **vascular spasm & vasoconstriction** of the platelet activation process

DECREASE blood flow and pressure in the vessel

what happens when the **platelet plug fills damaged space** during the platelet activation process

block disrupted surface of vessel

what happens when **coagulation causes activation of proteins to result in clotting** during the platelet activation process

plug stabilizing fibrin network traps other blood cells like a bandaid