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Chapter 19. Blood. Blood Overview. spin blood separate into 2 parts (3). liquid cells (formed elements). WBC’s. RBC’s. Blood. chapter outline:. Overview Plasma Formed elements RBC’s WBC’s platlets (fragments) hemostasis. Blood Overview. fluid CT - PowerPoint PPT Presentation
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Chapter 19
Blood
Blood Overview
WBC’s
RBC’s
liquid
cells(formed
elements)
spin blood
separate into 2 parts (3)
Blood
OverviewPlasmaFormed elements
RBC’sWBC’splatlets (fragments)
hemostasis
chapter outline:
Blood Overview
fluid CTpart of the cardiovascular system
(heart, vessels)
provide nutrients, O2, chemical messagesremoves wastesprovide protection
to/from/for all the cells of the body
Blood Overview
•transport:dissolved gasesnutrientshormoneswastes
•regulate:ionic composition and pH of body fluids
Blood Overview
•restrict fluid lose at injury
•stabilize body temperature
•defend against toxins and pathogens
Blood Overview
•restrict fluid lose at injury
•stabilize body temperature
•defend against toxins and pathogens
Blood Overview
plasma
~55% of blood
H2O 92%plasma proteins 7%ionsnutirentswasteshormones
Blood Overview
formed elements
produced through hemopoiesis
99.9% RBC’s0.1 % WBC’s and platlets
Blood Overview
whole blood
•38˚ C•5x more viscous than H2O
(sticky, thick)
•slightly alkalaipH 7.35 - 7.45
5-6 L in average adult male (165)4-5 L in average adult female (125)
(7% of body weight)
Clinical Note
blood donations
median cubital veinvenipuncture
easy to findthin walls than arterieslower bp than arteries
Clinical Note
capillary blood
finger tipearlobetoe / heel (infant)
small quantity (drops)
Clinical Note
arterial blood
radial or brachial artery
check blood gases
Stop here 3/21Lec #29
Blood plasma
body fluids
ICFECF
interstitial fluidblood plasma
Blood plasma
similar in composition to interstitial fluid (ECF) (different than ICF)
but different than ECF in:
dissolved gases (O2, CO2)(always being used by
cells)
dissolved proteins(don’t cross capillary
walls)
Blood plasma
7.6 g% (5x ICF)7.6 grams / 100 ml plasma
large size and globular shapeprevents them from leaving vessels
three classes of proteins:albuminsglobulinsfibrinogen
proteins:
Blood plasma
proteins:
albumins
60% of plasma proteinsmade in livertransport:
fatty acidshormonesother stuff
Blood plasma
proteins:
globulins35% of plasma proteinstwo typesimmunoglobulins
transport globulinsaka., antibodies (Ab)
hormone-binding (thyroid H)
metalloaproteins (iron)
apolipoproteins (lipids)
steroid-binding (testosterone)
Blood plasma
proteins:
fibrinogen4% of plasma proteinsblood clotting
converted to fibrin (strings)(framework for clot)
plasma without clotting stuff= serum
Blood plasma
proteins:
other plasma proteinsvarious
hormones
origins of proteinsliver makes 90%
plasma cells make antibodies (Ab)
100 keys pg. 643
“Your total blood volume, in liters, is roughly equal to 7% of your body weight (in kilograms). Approximately half the volume of whole blood consists of cells and cell products. Plasma resembles interstitial fluid, but it contains a unique mixture of proteins not found in other extracellular fluids.”
Clinical Note
Plasma expanders
used to increase blood volume
(buy time to determine blood type)
isotonic (normal) saline solutionsshort-lived diffuse into interstitial fluid and
cells
Ringer’s solution has lactate (slows diffusion)
Dextran in saline
Clinical Note
Plasma expanders
temporarily replace blood volume
don’t help increase O2 carried
need to give or make new RBC’s
Formed elements
RBC’saka., red blood cells
erythocytes
contain pigment molecule hemoglobin
Hb + O2 HbO2
(dark) (bright red)
RBC’s
Quantity
# RBC’s in one µl (microliter)(1 mm3)
about 5,000,000 cells / µlx 5 L of blood
25,000,000,000 RBC’s in adult
RBC’s
Quantity
percentage of whole blood occupied by RBC’s
hematocrit
average is about 45 males42 females
RBC’s
Quantity
What factors may affect the hematocrit ?
increase
decrease
dehydrationEPO stimulation
bleedingproblems with RBC production
RBC’s
Structure
unusual cellslack most organelles
(nucleus, mitochondria, etc)except cytoskeleton
biconcave discs
fig. 19-2c
fig. 19-2d
RBC’s
Structure
shape
large surface area to volume ratio
absorption and release of O2
form stacks to go through vessels
can bend and flex to get through narrow capillaries
RBC’s
Structure
lack of organelles
cannot dividecannot synthesize proteinscannot repair itself
short life-span (120 days)replace ~1% each day
low energy demands
RBC’s
Structure
What do they have inside ?
95% of proteins inside the cell is
hemoglobin (Hb)14 g%
RBC’s
Structure of Hemoglobin
complex structure4 polypeptide chains
2 alpha () chains2 beta () chains
(amino acids)
each chain has a hemepigment moleucleFe2+
fig. 19-3
RBC’s
Structure of Hemoglobin
280 million Hb molecules/RBC
one RBC can carry over a billion O2
O2 bound depends on [O2]if [CO2] is high
bind to Hbcarbaminohemoglobin
RBC’s
Structure of Hemoglobin
low hematocritlow Hb
reduced O2-carrying capacity
= anemia many forms
reduced flow of O2 to tissues
weakness, lethargy, confusion
RBC’s
Formation / Turnover
exposed to severe mechanical stresscannot repair themselves
macrophagesengulf old/damaged cellsengulf cell parts after hemolysis
RBC’s
Formation / Turnover
hemolysis
releases Hb from cells
if phagocytosed - recycledif not, eliminated by kidney
hemoglobinuria
red or brown urinelots of Hb in urine
RBC’s
Formation / Turnover
hemolysis
hemoglobinuria
hematuria
intact RBC’s in urinemeans kidney damage or
blood vessel damage
RBC’s
Formation / Turnover
recycling (by macrophages)
globin proteinsamino acids
reused
RBC’s
Formation / Turnover
recycling (by macrophages)
heme (without Fe2+)
bilverdin (greenish) (bruise)
bilirubin (yellowish)(jaundice)
excretion (urine, feces)
RBC’s
Formation / Turnover
recycling
Fe2+ (if free, is toxic to cells)
transported to bone marrowby transferrin
used to make new RBC’sneed 26 mg/day
1-2 mg is usually enoughmost is recycled
RBC’s
Formation / Turnover
recycling
too little Fe2+
reduction of RBC production
dietary deficiencyiron absorption
iron-deficiency anemia
RBC’s
Formation / Turnover
recycling
too much Fe2+
excessive buildup in heartlinked to heart disease
excessive buildup in liver
fig. 19-4
to here 3/23lec # 30
100 Keys (pg. 649)
“Red blood cells (RBC’s) are the most numerous cells in the body. They remain in circulation for approximately 4 months before being recycled; several million are produced each second. The hemoglobin inside RBCs transports oxygen from the lungs to the peripheral tissues; it also carries carbon dioxide from the tissues to the lungs.”
RBC’s
Production
embryo yolk sacfetus liver, spleenadults red bone marrow
(aka., myeloid tissue)
erythropoiesis
RBC’s
Production
hemocytoblast myeloid stem cell proerythroblasts - - - normoblasts (sheds nucleus)
reticulocyte (enter blood)
mature RBC
RBC’s
Production
fig. 19-5
RBC’s
Regulation of Production
requirements:
amino acidsironvitamins
B6
folic acidB12 meat/dairy products
absorption requiresintrinsic factor
RBC’s
Regulation of Production
requirements:
B12
if not enough eatenor absorbed
pernicious anemia
RBC’s
Regulation of Production
stimulated by EPOerytropoietinerythropoiesis stimulating
hor.
made by peripheral tissues especially kidney when exposed to low oxygen levels
hypoxia
RBC’s
Regulation of Production
what might trigger kidneyto release EPO?
anemiareduced blood flow to kidneylow O2 in lungs
(disease or high altitude)lung damage
RBC’s
Regulation of Production
effects of EPO
stimulates cell division inerythroblasts and stem
cells
stimulates Hb synthesis and maturation of RBC’s
RBC’s
Regulation of Production
effects of EPO
RBC production canincrease from
3,000,000 cells/second to
30,000,000 cells/second
RBC’s
Regulation of Production
effects of EPO
important following blood loss
given to healthy person(Olympic endurance athletes)blood can carry more O2
but, hematocrit rises (65+)blood get thickerstrain on heart
RBC’s
Regulation of Production
effects of EPO
same applies to blood doping
RBC’s
Blood testing
table 19-1
table 19-1
100 Keys (pg. 649)
“Red blood cells (RBC’s) are the most numerous cells in the body. They remain in circulation for approximately 4 months before being recycled; several million are produced each second. The hemoglobin inside RBCs transports oxygen from the lungs to the peripheral tissues; it also carries carbon dioxide from the tissues to the lungs.”
Blood typing
antigens“foreign” moleculescan trigger immune response
cells (including RBC’s) haveproteins on their surface
your immune system “ignores” the molecules on the surface of your cells because they are “self”
Blood typing
your body makes antibodies (Ab)(aka., immunoglobulins)
to attack and destroy antigens
There are three (of 50) important “antigens” used for blood typing
ABRh
Blood typing
if your cells normally have A on surface
(A is “self”)
your immune system will ignore it, but has antibodies to attack B
(anti-B antibodies)
You have type A blood
Blood typing
if your cells normally have B on surface
(B is “self”)
your immune system will ignore it, but has antibodies to attack A
(anti-A antibodies)
You have type B blood
Blood typing
if your cells have A & B on surface(both are “self”)
your immune system will ignore them
You have type AB blood
Blood typing
if your cells have neither on surface(neither are “self”)(both are foreign)
your immune system has antibodies to attack both
You have type O blood
fig. 19-6
agglutination
hemolysis
Genetics of blood groupings:
ABO system
three alleles
IA
IB
i
IA IA
IA iIB IB
IB iIA IB
i i
AABBABO
DOMINANTrecessive
Other blood groupings:
ABO system
Rh system
C, D, E: close on same chromosome
Dominant/recessive
C, D, or E Rh positive
ccddee Rh negative
Blood typing
if your cells have Rh factor on surface(Rh is “self”)
your immune system will ignore it
You have type Rh+ (positive) blood
Blood typing
if your cells lack Rh factor on surface(Rh is “foreign”)
your immune system will make antibodies to attack it
You have type Rh- (negative) blood
table 19-2
Blood typing
cross reaction
Ab + RBC agglutinationand hemolysis
blood transfusiontest for
compatability
Blood typing
standard test
determine donor’s and recipient’s blood type using ABO and Rh systems
mix drops of blood withanti-Aanti-Banti-Rh
fig. 19-7
A+
B+
AB+
O-
universaldonor
fig. 19-7
Blood typing
standard test
just tested 3 of 50+ possible antigens
if time and facilities allow:cross-match testing
mix donor and recipient bloodand look for problems
Blood typing
HDN
Hemolytic disease of the newborn
Blood typing
HDN