Chapter 18: Blood Flashcards
Blood
continuously regenerated connective tissue
Blood is transported through what sytem?
cardiovascular system
Arteries
transport blood away from heart
Veins
transport blood toward heart
Capillaries
allow exchange between blood and body tissues
Formed elements
- erythrocytes
- leukocytes
- platelets
- plasma
Erythrocytes
transport respiratory gases in the blood
Leukocytes
defend against pathogens
Platelets
help form clots to prevent blood loss
Plasma
fluid portion of blood
Functions of the blood
- transportation
- protection
- regulation of body conditions
Regulation of body conditions
- body temperature
- body pH
- fluid balance
Plasma is composed of what proteins
- albumins (58%)
- globulins (37%)
- fibrinogen (4)
- regulatory proteins (<1%)
Plasma is composed of
- water (92%)
- plasma proteins (7%)
- dissolved molecules and ions (1%)
Plasma is an _____________ fluid
extracellular
Different types of leukocytes in the blood
- neutrophils (most numerous)
- lymphocytes
- monocytes
- basophils (least numerous)
- eosinophils
Blood is a ________ solution
colloid
What is a colloid solution
a collection or mass of proteins in a solution
Water is attracted to
salts, sugars, and proteins
Plasma proteins exert ________________________
colloid osmotic pressure (COP)
Colloid osmotic pressure (COP)
- prevents loss of fluid from blood as it moves through capillaries
- helps maintain blood volume and blood pressure
Serum
blood plasma without clotting proteins (fibrin)
albumins
- exert the greatest colloid osmotic pressure
- act as transport proteins for some lipids, hormones, and ions
globulins
- smaller alpha-globulins and larger beta-globulins
- transport some water-insoluble molecules, hormones, metals, ions
gamma-globulins (antibodies)
part of the body’s defense and immobilize pathogens
fibrinogen
- contributes to blood clot formation
- following trauma, it is converted to insoluble fibrin strands
blood pH is slightly ___________
alkaline
hemacrit
percentage of the volume of all formed elements in the blood
buffy coat
- makes up the middle layer
- composed of leukocytes and platelets
- forms 1% of the hemacrit
blood smear
all of the components of the formed elements can be viewed
regulatory proteins
includes enzymes and hormones
hematopoiesis (hemopoiesis)
the production of formed elements in the blood
blood is also considered a ___________
solution
blood as a solution
- contains dissolved organic and inorganic molecules and ions
- include electrolytes, nutrients, gases, waste products
rouleaux
when red blood cells stack together in narrow spaces
erythrocytes
- small, lack a nucleus and cellular organelles
- packed with hemoglobin
- biconcave disc structure
- transport oxygen and carbon dioxide between tissues and organs
hemoglobin
- red-pigmented protein
- transports oxygen and carbon dioxide
- each hemoglobin molecule is composed of four globins, two alpha chains and two beta chains
- each chain has a heme group
heme group
a porphyrin ring with an iron ion in its center
oxygen binds to ________ ion
iron
carbon dioxide binds to ________________ not iron
globin
hematopoiesis is formed in _____________________
red bone marrow
the stem cell that is used to make erythrocytes, platelets, granulocytes, and some agranulocytes
hemocytoblast
erythropoiesis
the production of red blood cells
the process of erythropoiesis begins with a ______________ stem cell
myeloid
erythropoietin (EPO)
hormone produced primarily in the kidneys
a myeloid stem cell that is under the influence of ______________ forms a progenitor cell
multi-CSF (colony-stimulus factor)
an erythrocyte is made after the ________ is ejected from the cell
nucleus
the process of thrombopoiesis begins with a _____________ stem cell
myeloid
thrombopoietin forms a ______________
megakaryocyte
from the megakaryocyte, proplatelets form and eventually become ___________
platelets
the process of leukopoiesis can either form
- granulocytes
- agranulocytes
using a progenitor cell, leukopoiesis forms the granulocytes called ___________, ____________, and ____________ as well as ______________
eosinophil, basophil, and neutrophil/ monocytes
to produce agranulocytes in leukopoiesis, a _______________ stem cell must be used first
lymphoid
from the lymphoid cell, what 3 agranulocytes are made?
1- b-lymphocyte
2- t-lymphocyte
3- natural cell killer
granulocytes
have visible granules seen with a light microscope
agranulocytes
have smaller granules that are not visible with light microscope
maximum lifespan of an erythrocyte
120 days
erythrocyte destruction
- old erythrocytes phagocytized in spleen or liver by macrophages
- broken down into their 3 components: globin, iron ion, ironless heme
- the amino acid pieces from the ironless heme is converted to biliverdin
- biliverdin is turned into bilirubin
- bilirubin is released into the bloodstream and transported by albumin to the liver
- bilirubin removed from blood by liver
- bile stored in the gallbladder excreted into small intestines
- bilirubin converted to urobilinogen in small intestine
- it can either be converted to urobilin in the kidneys and excreted in the urine or converted to stercobilin in the large intestine and expelled in the feces
biliverdin
green-pigment
bilirubin
yellowish pigment in bile that helps handle fats in the digestive tract
urobilinogen
made in the small intestines
urobilin
a yellow-pigment that is excreted by the kidneys
stercobilin
brown pigment that is expelled from the body in feces
what happens to globin once it has been broken down from an erythrocyte
recycled and used for new proteins
what happens to the iron ion once it has been removed from the heme
stored in the liver until it is needed for RBC production
bile
helps handle fats and enhances fat digestion
anemia
either the percentage of erythrocytes is lower than normal or the oxygen-carrying capacity is reduced
hemorrhagic anemia
due to blood loss
pernicious anemia
failure to absorb vitamin B12 due to dietary problem
sickle-cell disease
genetic defect; abnormal hemoglobin
surface antigens
projecting from the erythrocyte membrane
type A blood
- surface antigen A only
- has anti-B antibodies in plasma
type B blood
- surface antigen B only
- has anti-A antibodies in plasma
type AB blood
- surface antigens A and B
- neither anti-A or anti-B antibodies in plasma
type O
- have neither antigen
- both anti-A and anti-B antibodies in plasma
Rh positive
- surface antigen D
- no anti-D antibodies
Rh negative
- no surface antigen D
- no anti-D antibodies unless exposed to Rh-positive blood
universal recipient blood type
AB+
universal donor blood type
O-
antigen
identification marker
agglutination
the process of clumping erythrocytes when antibodies find antigens
an adult human has __ L of blood
5
hemolytic disease of the newborn (HDN)
- Rh negative mom may be exposed to Rh+ blood during childbirth of Rh+ baby
- mom now with anti-D antibodies
- in future pregnancy, may cross placenta, destroy fetal RBCs
- prevention; give pregnant Rh negative woman special immunoglobulins
hemolysis
rupture of erythrocytes
leukocytes
- defend against pathogens
- contain nucleus and organelles, but not hemoglobin
- motile, flexible, and large
- most not in blood but in tissues
diapedesis
process of squeezing through blood vessel wall
chemotaxis
attraction of leukocytes to chemicals at an infection site
neutrophils
- most numerous leukocytes in blood
- enter tissue spaces and phagocytize infectious pathogens
- numbers rise dramatically in chronic bacterial infection
eosinophils
- 1-4% of leukocytes
- phagocytize antigen-antibody complexes, allergens or parasites
- active in cases of parasitic worm infection
basophils
- they “sound the alarm”
-mast cell - histamine and heparin release
histamine release causes
increase in blood vessel diameter and capillary permeability (classic allergy symptoms)
heparin release
inhibits blood clotting
monocytes
- 2-8% of blood leukocytes
- take up residence in tissues
- transform into large phagocytic cells, macrophages
- phagocytize bacteria, viruses, debris
lymphocytes
- reside in lymphoid organs and structures
- 20-40% of blood leukocytes
- three categories:
1- t-lymphocytes
2- b-lymphocytes
2- NK (natural killer cells)
t-lymphocytes
manage immune response
b-lymphocytes
become plasma cells and produce antibodies; “handcuffs”
NK (natural killer cell)
attack abnormal and infected tissue cells
leukopenia
- reduced number of leukocytes
- increases risk of infection
leukocytosis
- elevated leukocyte count
- may be caused by recent infection or stress
differential count
- measures amount of each type of leukocyte and whether any are immature
- useful for clinical diagnosis
leukemia
- cancerous-like growth of WBC
- abnormal development and proliferation of leukocytes
- decrease in erythrocyte and megakaryocytic lines
- results in anemia and bleeding
- lowers BP and platelets
platelets (thrombocytes)
- no nucleus
- break off of megakaryocytes in red marrow
- important role in blood clotting
- circulate for 8 to 10 days; then broken down and recycled
hemostasis
stoppage of bleeding
embolism
a free-flowing blood clot
3 overlapping phases of hemostasis
1- vascular spasm
2- platelet plug formation
3- coagulation phase
vascular spasm
- blood vessel constriction
- first phase in response to blood vessel injury
- limits blood leakage
- greater vasoconstriction with greater vessel damage
platelet plug formation
platelets arrive at the site of injury and adhere to exposed collagen fibers
thrombocytopenia
- low platelet count
- impairs all phases of hemostasis
coagulation phase
- blood clotting
- network of fibrin forms a mesh
- fibrin comes from soluble precursor fibrinogen
- mesh traps erythrocytes, leukocytes, platelets, plasma proteins to form clot
plasmin
helps dissolve the clot after the cells have been repaired
if blood loss is greater than 10%
- SNS increases vasoconstriction, heart rate, force of heart contraction
- blood redistributed to the heart and brain
- effective in maintaining blood pressure until 40% of blood loss
