White blood cells
Platelets
Red blood cells
Artery
• Deliver O2
• Remove metabolic wastes
• Maintain temperature, pH, and fluid volume
• Protection from blood loss- platelets
• Prevent infection- antibodies and WBC
• Transport hormones
Plasma-55%
Formed elements-45%
Buffy coat-<1%
90% Water8% Solutes:• Proteins
Albumin (60 %)Alpha and Beta GlobulinsGamma Globulinsfibrinogens
• Gas• Electrolytes
• Organic NutrientsCarbohydratesAmino AcidsLipidsVitamins
• Hormones• Metabolic waste
CO2Urea
• Leukocytes
• Platelets
• Erythrocytes (red blood cells)
• Leukocytes (white blood cells)
• Platelets (thrombocytes)
Erythrocytes
Erythrocyte7.5m in dia Anucleate- so can't reproduce; however, repro
in red bone marrow Hematopoiesis- production of RBC Function- transport respiratory gases Hemoglobin- quaternary structure, 2 chains
and 2 chains Lack mitochondria. Why? 1 RBC contains 280 million hemoglobin
molecules Men- 5 million cells/mm3
Women- 4.5 million cells/mm3
Life span 100-120 days and then destroyed in spleen (RBC graveyard)
Hematopoiesis
• Hematopoiesis (hemopoiesis): blood cell formation –Occurs in red bone marrow of
axial skeleton, girdles and proximal epiphyses of humerus and femur
Hematopoiesis
• Hemocytoblasts (hematopoietic stem cells)– Give rise to all formed elements– Hormones and growth factors push the cell
toward a specific pathway of blood cell development
• New blood cells enter blood sinusoids
Erythropoiesis
• Erythropoiesis: red blood cell production
– A hemocytoblast is transformed into a proerythroblast
– Proerythroblasts develop into early erythroblasts
Erythropoiesis
– Phases in development1. Ribosome synthesis
2. Hemoglobin accumulation
3. Ejection of the nucleus and formation of reticulocytes
– Reticulocytes then become mature erythrocytes
Figure 17.5
Stem cell
HemocytoblastProerythro-blast
Earlyerythroblast
Lateerythroblast Normoblast
Phase 1Ribosomesynthesis
Phase 2Hemoglobinaccumulation
Phase 3Ejection ofnucleus
Reticulo-cyte
Erythro-cyte
Committedcell
Developmental pathway
Regulation of Erythropoiesis
• Too few RBCs leads to tissue hypoxia• Too many RBCs increases blood
viscosity• Balance between RBC production and
destruction depends on– Hormonal controls – Adequate supplies of iron, amino acids,
and B vitamins
Hormonal Control of Erythropoiesis
• Erythropoietin (EPO)–Direct stimulus for erythropoiesis
–Released by the kidneys in response to hypoxia
Hormonal Control of Erythropoiesis
• Causes of hypoxia– Hemorrhage or increased RBC destruction
reduces RBC numbers– Insufficient hemoglobin (e.g., iron
deficiency)
– Reduced availability of O2 (e.g., high altitudes)
Hormonal Control of Erythropoiesis
• Effects of EPO– More rapid maturation of committed bone
marrow cells– Increased circulating reticulocyte count in
1–2 days
• Testosterone also enhances EPO production, resulting in higher RBC counts in males
Formation & Destruction of RBCs
Anemia- when blood has low O2 carrying capacity; insufficient RBC or iron deficiency.Factors that can cause anemia- exercise, B12 deficiencyPolycythemia- excess of erythrocytes, viscosity of blood;8-11 million cells/mm3
Usually caused by cancer, tissue hypoxia, dehydration; however, naturally occurs at high elevationsBlood doping- in athletesremove blood 2 days before event and then replace it; Epoetin;- banned by Olympics.
Sickle-cell anemia-
HbS results from a change in just one of the 287 amino acids in the chain in the globin molecule.
Found in 1 out of 400 African Americans.
Abnormal hemoglobin crystalizes when O2 content of blood is low, causing RBCs to become sickle-shaped.
Homozygous for sickle-cell is deadly, but in malaria infested countries, the heterozygous condition is beneficial.
Genetics of Sickle Cell Anemia
Genetics of Sickle Cell AnemiaGenetics of Sickle Cell AnemiaGenetics of Sickle Cell AnemiaGenetics of Sickle Cell Anemia
GranulocytesNeutrophils- 40-70%Eosinophils- 1-4%Basophils- <1%
AgranulocytesMonocytes- 4-8%
Lymphocytes- 20-45%
Never let monkeys eat bananas
4,000-11,000 cells/mm 3
Basophil Eosinophil
Neutrophil
Lymphocyte
Monocyte
platelet
neutrophil
neutrophilRBC
eosinophil
monocyte
lymphocyte
lymphocytebasophil
monocyte
ID WBC’s
Leukocyte Squeezing Through Capillary Wall
• Leukopenia
• Abnormally low WBC count—drug induced
• Leukemias
• Cancerous conditions involving WBCs
• Named according to the abnormal WBC clone involved
• Mononucleosis• highly contagious viral disease caused by
Epstein-Barr virus; excessive # of agranulocytes; fatigue, sore throat, recover in a few weeks
Platelets
• Small fragments of megakaryocytes• Formation is regulated by
thrombopoietin• Blue-staining outer region, purple
granules• Granules contain serotonin, Ca2+,
enzymes, ADP, and platelet-derived growth factor (PDGF)
Figure 17.12
Stem cell Developmental pathway
Hemocyto-blast Megakaryoblast
PromegakaryocyteMegakaryocyte Platelets
Hemostasis- stoppage of bleeding
Tissue Damage
Platelet Plug
Clotting Factors
Platelets: 250,000-500,000 cells/mm3
Hemostasis:
4. Coagulation
1. Vessel injury
2. Vascular spasm
3. Platelet plug formation
Hemostasis(+ feedback)
Prothrombin
Thrombin
Fibrinogen Fibrin
Clotting Factorsthromboplastin
Traps RBC & platelets
Platelets release thromboplastin
Blood Clot
Fibrin thread
Platelet
RBC
Disorders of Hemostasis
• Thromboembolytic disorders: undesirable clot formation
• Bleeding disorders: abnormalities that prevent normal clot formation
Thromboembolytic Conditions
• Thrombus: clot that develops and persists in an unbroken blood vessel– May block circulation, leading to tissue death
• Embolus: a thrombus freely floating in the blood stream– Pulmonary emboli impair the ability of the body to
obtain oxygen– Cerebral emboli can cause strokes
Thromboembolytic Conditions
• Prevented by– Aspirin
• Antiprostaglandin that inhibits thromboxane A2
– Heparin• Anticoagulant used clinically for pre- and
postoperative cardiac care
– Warfarin• Used for those prone to atrial fibrillation
Thrombocytosis- too many platelets due to inflammation, infection or cancer
Thrombocytopenia- too few platelets• causes spontaneous bleeding• due to suppression or destruction of bone
marrow (e.g., malignancy, radiation)– Platelet count <50,000/mm3 is diagnostic – Treated with transfusion of concentrated
platelets
• Impaired liver function– Inability to synthesize procoagulants
– Causes include vitamin K deficiency, hepatitis, and cirrhosis
– Liver disease can also prevent the liver from producing bile, impairing fat and vitamin K absorption
Bleeding Disorders
• Hemophilias include several similar hereditary bleeding disorders
• Symptoms include prolonged bleeding, especially into joint cavities
• Treated with plasma transfusions and injection of missing factors
Hemophiliac- a sex-linked recessive trait, primarily carried by males (x chromosome)
Type AType AType BType BType ABType ABType OType O
Blood type is based on the presence of 2 major antigens in RBC membranes-- A and BBlood type Antigen Antibody
A A anti-BB B anti-A
A & B AB no anti bodyNeither A or B O anti-A and anti-B Antigen- protein on the surface of a RBC membrane
Antibody- proteins made by lymphocytes in plasma which are made in response to the presence of antigens.They attack foreign antigens, which result in clumping (agglutination)
Type A
ABO Blood TypesABO Blood Types
Produces Produces anti-B anti-B antibodiesantibodies
b
b
b
b
b
b
b
b
Type B
ABO Blood TypesABO Blood Types
Produces Produces anti-A anti-A antibodiesantibodies
a
a
a
a
a
a a
a
aa
Type AB
ABO Blood TypesABO Blood Types
Produces Produces neither neither anti-A nor anti-A nor anti-B anti-B antibodiesantibodies
Type O
ABO Blood TypesABO Blood Types
Produces Produces both anti-A both anti-A and anti-B and anti-B antibodiesantibodies
a
a
a
a
a
aa
a
aa
b
b
b
b
b
b
b
b
Rh Factor and Pregnancy
RH- indicates no protein
RH+ indicates proteinRH+ indicates protein
Rh Factor and
Pregnancy
Rh+ mother w/Rh- baby– no problemRh- mother w/Rh+ baby– problemRh- mother w/Rh- father– no problemRh- mother w/Rh- baby-- no problem
RhoGAM used @ 28 weeks
Type AB- universal recipients
Type O- universal donor
Rh factor:
Rh+ 85% dominant in pop
Rh- 15% recessive
Blood Type Clumping Antibody
A antigen A anti-A serum antibody anti-b
B antigen B anti-B serum antibody anti-a
AB antigen A & B anti A & B serum -
O neither A or B no clumping w/ either anti A or B anti-a, anti-b
Figure 17.16
SerumAnti-A
RBCs
Anti-B
Type AB (containsagglutinogens A and B;agglutinates with bothsera)
Blood being tested
Type A (containsagglutinogen A;agglutinates with anti-A)
Type B (containsagglutinogen B;agglutinates with anti-B)
Type O (contains noagglutinogens; does notagglutinate with eitherserum)
Blood Type & Rh How Many Have It Frequency
O Rh Positive 1 person in 3 37.4%
O Rh Negative 1 person in 15 6.6%
A Rh Positive 1 person in 3 35.7%
A Rh Negative 1 person in 16 6.3%
B Rh Positive 1 person in 12 8.5%
B Rh Negative 1 person in 67 1.5%
AB Rh Positive 1 person in 29 3.4%
AB Rh Negative 1 person in 167 .6%
ABO Blood Types
PhenotypePhenotype GenotypeGenotypeOO i ii iAA I I A A I I AA or I or I A A
iiBB I I B B I I BB or I or I B B
iiABAB I I A A I I BB
Type A and Type B cross
IA
IA
IB i
IAiIAIB
IAIB IAi
Punnett square
INQUIRY1. What is an erythrocyte, leukocyte, and thrombocyte?2. What 2 things do red cells lack compared to white
cells?3. What dietary component is needed for the production
of red blood cells?4. The largest cells in the blood that leave the
bloodstream to become macrophages are ____.5. In an acute infection, the white cell count would show
as ______.6. Erythroblastosis fetalis , also known as hemolytic
newborn disease, occurs in ____ mothers carrying ____ fetuses.
7. What antigens and antibodies found on AB red cells?8. In a transfusion, what type blood can you give a type
O person?