Module 13: Blood and Blood Vessels Flashcards
3 functions of blood
distribution (oxygen, CO2, nutrients, waste, hormones)
regulation (body temp, pH, volume of fluid)
protection (controls bleeding, defends infection)
Characteristics of blood
Fluid connective tissue Stickly Salty Scarlet/dark red color 8% of body's weight 4-6L pH 7.35-7.45 Higher than body temp
Blood is formed of 2 things
plasma and formed elements
formed elements
rbc, wbc, platelets
Hematocrit
percentage of erythrocytes in whole blood
Males: 40-54%
Females: 38-46%
Buffy coat of centrifuged blood
leukocytes and platelets
Erythrocytes
120 day lifespan
Produced at rate of 2mi/second
Hemoglobin ranges
Adult male: 135-180g/L
Adult female: 120-160g/L
infants: 140-200g/L
Leukocytes
lifespan of a few days to 15 years
contain granulocytes or may be agranulocytes
Granulocytes
neutrophils
eosinophils
basophils
Agranulocytes
lymphocytes
monocytes
Thrombocytes
platelets
fragments of megakaryocytes
Lifespan of 7 days
Plasma
intercellular matrix in blood
Straw color
55% of blood volume
90% water and 10% ions, proteins, fats, glucose, vitamins, nutrients, hormones, oxygen, co2, antibodies, waste
vessels are lined with
endothelium (single layer of squamous epithelial cells)
5 components of hemostasis
Form a clot: vasoconstriction, platelet plug formation, coagulation
Braking system: Fibrinolysis, Natural inhibitors/anticoagulants
vasoconstriction
smooth muscle in vessel walls constrict
platelets move toward injury site
Platelet plug formation
contact with collagen
platelet plug fills gap to prevent further blood loss
coagulation
only if injury is severe and requires actual clot
coagulation factors activated
prothrombin to thrombin
Fibrin threads form mesh that adheres to the damaged tissue and traps blood cells and platelets to form the clot
Fibrinolysis
after healing, clot is dissolved by enzymes
Natural inhibitors/anticoagulants
some coagulation factors escape area of injury
natural substances in blood with dispose of escaped factors
Heparin, TPA, Streptokinase
Vitamin K
produced by bacteria in large intestine
absorbed into bloodstream by colon
Stimulates liver cells to increase synthesis of prothrombin
Newborns get injection of vit K to prevent abnormal bleeding as they can’t produce it right away
ABO groups
based on specific antigens on rbc membrane and antibodies in plasma
antigen aka
agglutinogens
antibodies aka
agglutinins
Type A blood
A antigens on RBC
Anti B antibodies in plasma
Type B Blood
B antigens on RBC
Anti A antibodies in plasma
Types AB Blood
A and B antigens on RBC
No antibodies in plasma
Type O Blood
Neither A or B antigens on RBC
Anti A and anti B antibodies in plasma
Universal recipient
type AB because they have no antibodies
Universal donor
type O because they have either types a or b antigens
anastomosis
union of the branches of 2 or more blood vessels supplying blood to the same region
collateral circulation
blood can be supplied to the area by an alternate route
end arteries
arteries that do not anastomose
3 tunics (layers) of blood vessels
Tunica Interna (Endothelium, simple squamous epi cells) Tunica Media (muscular) Tunica Externa (elastic tissue/collagen)
ECG waves
P - SA node through walls of atria
QRS - spread of impulse through walls of ventricles and recovery of the atria after contraction
T - recovery of the ventricles after contraction
Blood pressure
highest in arteries
Lowest in veins
Blood pressure cuff
sphygmomanometer used with a stethoscope
Regular blood pressure
120/80mmHg
systolic (pressure during contraction of ventricle)/ diastolic (pressure during relaxation of ventricles)
heart rate is controlled by
cardiac center in medulla of brain
receives impulses from pressoreceptors and chemoreceptors
tachycardia
rate above 100bpm
bradycardia
rate below 60bpm
normal heart rate
72bpm
Hemophilia
inability to clot blood sex-linked hereditary disorder affects mostly males transmitted by females normal plt, but lack of plasma protein for coagulation
Leukemia
blood cancer
chemotherapy and antineoplastic agents for treatment
MI
myocardial infarction
blockage of coronary arterial circulation
tissue dies without oxygen
Coronary bypass surgery/angioplasty to reduce heart damage
Hypertension
blood pressure above 140/90mmHg
causes heart failure, kidney disease, stroke
Arteriosclerosis
hardening of arteries
caused by fatty deposits that develop in inner lining of blood vessel
can cause MI and stroke
Effects of aging on blood system
left ventricle gets smaller
valves thicken, heart murmur
decreased ability of heart response to stress
