Chapter 19: Blood Flashcards
What is included in the circulatory system?
-the heart
-blood vessels
-blood
what is the main function of the cardiovascular system?
to transport materials to and from the cells such as oxygen, carbon dioxide and nutrients
Blood
specialized fluid of connective tissue that contains cells suspended in a fluid matrix
what are the 4 functions of blood?
-transportation of dissolved substances
-regulation of pH and ions
-restriction of fluid losses at injury sites
-defense against toxins and pathogens
-stabilization of body temperature
2 function of the blood:
regulation of pH and ions :
-adding or subtracting by diffusion with interstitial fluid
-absorbs and neutralizes acids such as lactic acid from skeletal muscle
3 function of the blood:
restriction of fluid losses at injury site through clotting
4 function of the blood:
defense against toxins and pathogens through WBC
5 function of the blood:
stabilization of body temp through heat loss/heat retention
Whole blood is comprised of:
plasma and formed elements (cells and cell fragments)
Plasma
made mostly of water
-dissolved plasma proteins present
-nutrients/ions present
-similar to and exchanges fluids with interstitial fluid
What are the three types of formed elements?
-red blood cells (RBC)
-white blood cells (WBC)
-platelets (thrombocytes)
Red blood cells (erythrocytes)
transport oxygen
White blood cells (leukocytes)
are part of the immune system
Platelets (thrombocytes)
cell fragments involved in clotting
Hemopoiesis
the process of producing formed elements from myeloid and lymphoid cells
Fractionation
separation of whole blood for clinical analysis
3 general characteristics of blood
-38 or 100.4 degrees is normal temp
-high viscosity
-slightly alkaline pH
Blood makes up what percentage of body weight?
7%
Adult males have how many liters of blood?
5-6
Adult females have how many liters of blood?
4-5
Plasma makes up:
50-60% of blood volume
What materials are exchanged across capillary walls:
-water
-ions
-small nutrients
What are the main differences between plasma and interstitial fluid?
-the levels of O2 and CO2
-plasma proteins are too big to pass through capillary walls
What are the three classes of plasma proteins?
-albumins
-globulins
-fibrinogens
Albumins:
transport substances such as fatty acids, thyroid hormones, and steroid hormones
Fibrinogens:
make up the fibrin network and assist in clotting
-produce fibrin
Globulins:
are antibodies aka immunoglobulins
What is the other 1% of plasma comprised of?
changing quantities of specialized plasma proteins, enzymes, hormones, and prohormones
Where is plasma made?
the liver
RBCs make up what % of blood’s formed elements?
99.9%
RBC count:
the # of RBCs in 1 microliter of whole blood
Hematocrit
packed cell volume: the % if RBCs in centrifuged whole blood
RBC structure:
small, highly specialized disk that is thin in the middle and thicker around the edge
What is the lifespan of RBCs?
120 days
Hemoglobin
the main component that transports respiratory gases
Hemoglobin structure:
complex and quaternary structure
Fetal hemoglobin:
strong form of HGB found in embryo/fetus that takes oxygen from mother’s HGB at the placenta
carbaminohemoglobin
a compound of hemoglobin and carbon dioxide
Anemia:
low HCT or HGB
-multifactorial
Recycling RBCs
macrophages of liver, spleen, and bone marrow monitor and engulf RBCs before their membranes rupture
Hemoglobinuria
HGB breakdown products in urine due to excess hemolysis in blood stream
Hematuria
whole red blood cells in urine due to kidney or tissue damage
Hemoglobin recycling
phagocytes break hemoglobin down
Biliverdin
a green pigment found in bile that is produced when hemoglobin breaks down
-converted to bilirubin
Bilirubin
yellow bile excreted by the liver
-can cause jaundice if built up
Erythropoiesis
-RBC formation
-occurs in red bone marrow
Hemocytoblasts
stem cells in bone marrow that divide into myeloid or lymphoid stem cells
RBC maturation Day 4
ejection of the nucleus happens
RBC maturation days 5-7
cell becomes reticulocyte
Building red blood cells requires:
-amino acids
-iron
-vitamins B12, B6, and folic acid
Pernicious anemis
low RBC production due to low B12
Erythropoietin (EPO)
produced in the kidneys and tells body to make more blood
Surface antigens
cell surface proteins that identify cells to immune system (triggers immune response)
What are the 4 blood types?
A, B, AB, O
Rh factor
either positive or negative
Sensitized Rh- blood
when someone with Rh-negative blood is exposed to Rh-positive blood and develops antibodies against the Rh-positive blood
Erythroblastosis fetalis
a blood disorder that occurs when a mother and baby have incompatible blood types
Cross-reaction
transfusion reaction
WBCs
also called leukocytes
-do not have hemoglobin
-have nuclei and other organelles
WBC funtions
-defend against pathogens
-remove toxins and wastes
-attack abnormal cells
WBC movement
most WBCs live in connective tissue proper and lymphatic system organs
Circulating WBCs
migrate out of the bloodstream with gliding movements
What are the 5 types of WBCs?
-neutrophils
-eosinophils
-basophils
-monocytes
-lymphocytes
Neutrophils
most populous WBC ~50-70%
-have 10 hour life span
-have dense, 2-5 segment nucleus
True of False: Neutrophils are the first to attack bacteria.
TRUE
True of False: Neutrophils contribute to local inflammation and form pus.
TRUE
Eosinophils
make up 2-4% circulating WBC’s
-have a 2-lobed nucleus
-attack large parasites and toxic compounds
Eosinophil actions:
-sensitive to allergens
-control inflammation with enzymes that counteract inflammation caused by neutrophils
Basophils
-make up less than 1% of circulating WBCs
-very small
-migrate to site via capallaries
Histamie
dilates blood vessels
Heparin
prevents blood from clotting and enhances inflammation
Monocytes
-2-8% circulating WBCs
-large and spherical
-larger, kidney like nucleus
-become macrophages after 24 hrs
Macrophage actions:
-engulf large particles and pathogens
-secrete substances that attract immune system cells and fibroblasts to injured area
Lymphocytes
-20-30% circulating WBCs
-small, but larger than RBC
-large, round nucleus with thin cytoplasmic halo
Lymphocyte actions:
part of the body’s defense system of:
-T cells
-B cells
Natural Killer (NK) cells
T cells
-cell-mediated immunity
-attack foreign cells directly
-coordinates immune response
B cells
differentiate into plasma cells
Natural Killer Cells
immune surveillance
-detect and destroy abnormal tissue cells such as cancers
Leukopenia
abnormally low WBC
Leukocytosis
abnormally high WBC
Leukemia
extremely high WBC
WBC production:
all WBC originate from hemocytoblasts
Hemocytoblasts
produce myeloid and lymphoid stem cells
Myeloid stem cells
differentiate into progenitor cells which produce all WBCs except lymphocytes
Lymphocytes
produced by lymphocytes through lyphopoeises
WBCs except ___ develop fully in the bone marrow.
Monocytes
Monocytes develop into:
macrophages in peripheral tissue
Platelets
cell fragments involved in clotting
Platelet circulation:
circulate for 9-12 days
removed by phagocytosis in spleen
Thrombocytopenis
abnormally low PLTS
Thrombocytosis
abnormally high PLTS
What are the 3 functions of PLTS?
-release important clotting chemicals
-temporarily path damaged vessel walls
-actively contract tissue after clot formation
Thrombocytopoeisis
production of PLTS in the bone marrow
Megakaryocytes
-giant cells
-manufacture plts from cytoplasm
-produces 4k plts each
What are the 3 phases in cessation of bleeding?
-Vascular phase
-platelet phase
-coagulation phase
Vascular phase
a cut triggers vascular spasm (30 min contraction)
3 Steps of vascular phase?
-endothelial cells contract
-endothelial cells release local hormones/chemical factors
-endothelial cell membranes seals off blood flow
Platelet phase
-begins within 15 seconds of injury
Platelet adhesion
PLTS stick to endothelial surfaces, basal laminae, or exposed collagen fibers
Platelet aggregation
form platelet plug that closes small breaks
Prostacyclin
released by endothelial cells that inhibits platelet aggregation
Coagulation phase
-begins 30 seconds or more after injury
Extrinsic pathway
-begins inside the vessel wall
-damaged cells release TF that activates factor X (10)
Intrinsic pathway
-begins with circulating proenzymes within bloodstream
-PLTS release factor X
Common pathway
-enzymes activate factor X
-prothrombinase formed
-prothrombin converted to thrombin
-thrombin converts fibrinogen to fibrin
-positive feedback loop created to accelerate clotting
True of False: calcium ions and vitamin K are both essential to the clotting process.
TRUE
Fibrinolysis
slow process of dissolving clot
Plasminogen
produces plasmin that digests fibrin strands
