Honors Anatomy & Physiology

Blood

Barbers and surgeons were the early bloodletters, and the pole advertised their trade. The barbershop pole is striped red and white. Red represents blood, white represents the tourniquet, and the pole itself represents the stick that the patient squeezed to dilate the veins for easy puncturing. Fortunately, today’s barbers cut hair and not your jugulars.

Do Now: WHAT DO THE RED AND WHITE STRIPES OF A BARBERSHOP POLE REPRESENT?

Components

Small biconcave discs (7.5 µm)Anucleate w/no organelles

Advantage of no mitochondria?97% Hemoglobin (Hb) – binds reversibly w/O2

4 polypeptide chainsw/4 Fe Heme pigments (binds 4 O2)Ea/cell 250 million Hb (over 1 billion O2

molecules)Oxyhemoglobin (oxidation) vs. deoxyhemoglobin

(reduction)Amino acids binds to 20% of CO2 produced

making carbaminohemoglobin

Erythrocytes (RBC)

Straw colored sticky fluid90% WaterHomeostasis maintains compositionDissolved solutes

Glucose, fatty acids, amino acidsIons , hormones, gassesPlasma proteins

Albumin – maintains osmotic pressure w/ions

Blood Plasma

100 billion new blood cells ea/day!!!Maintains RBC countFormed in red bone marrow &

migrate to blood streamHemocytoblast stem cell

differentiates into a proerythroblast, as hemoglobin accumulates, organelles degenerate, causing indentation ( SA) forming reticulocyte (15 days)

Released into blood stream, mature in 2 days

Regulated by hormone erthropoiten (EPO) secreted by kidneys triggered by blood O2 levels

Hematopoiesis: Blood Cell Formation

Cannot grow, divide or synthesize new proteins. Why?

Hb degenerates 100-120 day lifespanSpleen traps dying rbc where

engulfed by macrophagesFe salvaged and stored Heme degraded into bilirubin

(yellow pigment) travels to liver where used to make bile, released in feces

Destruction of Erythrocytes

Fetal Hb vs. Adult HbBy day 28 of fetal

development – embryonic blood cells circulate in blood vessels

Fetal Hb (HbF) differs from adult HbA

HbF has a greater ability to pick up O2 b/c fetal blood less O2 rich than mothers

If fetal rbc destroyed so quick that liver cannot rid of bile fast enough causes infant jaundice

Diapedesis – able to leave by ameoboid motion to area of infection

WBC count double w/in a few hours if infected2 types:Granulocytes

Contain cytoplasmic granulesLarge cells w/lobed nucleiShorter life than RBCPhagocytic

Agranulocytes Lack granulesSpherical or kidney shaped nuclei

Leukocytes (WBC)

Granulocytes

Neutrophils (50-70%) Phagocytes kill bacteria and

some fungi Hydrolytic enzyme granules Inflammation sites

Basophils (0.5-1%) Histamine (vasodialator)

granules U or S shaped nucleus

Eosinophils (2-4%) Bilobed nucleus Digestive enzyme granules Attack parasitic worms to large

for phagocytosis

Lymphocytes (25%)Nucleus is most of

cellMostly in lymph

tissueT cells & B cells

Monocytes (3-8%)Largest leukocytesDifferentiate into

mobile macrophages

In order of abundance:Never Let Monkeys Eat Bananas

Agranulocytes

Derived from hemocytoplast stem cell in bone marrow

Cytoplasmic fragments last 10 days if not in clot

Form temporary plug ‘clot’ in ruptured bv

Once upon a time platelets:http://www.youtube.com/

watch?feature=fvwp&NR=1&v=vEmsaXA-go0

http://www.youtube.com/watch?v=9QVTHDM90io&feature=related

Platelets

1. Vascular Spasms (20-30 mins) Constriction of damaged bv to

restrict blood loss

2. Platelet Plug formation (1 minute) Platelets swell, form spiked

processes, and become sticky adhering to collagen fibers at site of damage

Platelets release seratonin (enhance spasms), ADP (attract more platelets) . Type of feedback?

3. Coagulation (blood clotting) Fibrinogen (soluble) triggered to

insoluble fibrin fomring a mesh to trap blood cells sealing damaged site until repaired

Hemostasis: Stoppage of bleeding

Hemophilia is a bleeding disorder caused by the deficiency of a clotting factor called factor VII, or the hemophilia factor. Hemophilia was common in the royal families of Europe; hence it was called the “royal disease.” Why was hemophilia so prevalent in the royal families? Hemophilia is genetically transmitted. Because of the tendency of the royals to intermarry (e.g. cousin marrying cousin), the gene carrying hemophilia was kept in the family and expressed frequently in the royal offspring. Queen Victoria of England carried the gene for hemophilia. Victoria, being both prolific and politically astute, placed a descendent on every throne in Europe. As each descendent married and intermarried, the incidence of hemophilia increased.

WHY WAS HEMOPHILIA CALLED THE “ROYAL DISEASE”?

Blood types & Transfusions

The surgeon recognized that the toe graft would be successful only if the blood supply to the toe was good. Frequently after surgery of this type, blood clots develop at the graft site, resulting in a decrease in blood flow. Leeches, or bloodsuckers, may be applied to the site of the graft. As the leech attaches to the skin to feed, it injects a potent anticoagulant. The leech and anticoagulant prevents blood clots at the graft site, thereby maintaining a good blood flow and improving the chances for successful grafting.

A TOE WAS ACCIDENTALLY SEVERED FROM ITS OWNER. IN REATTACHING THE TOE, THE SURGEON APPLIED LEACHES TO THE GRAFT SITE.