Transcript Document

Chapter 19
Blood Overview
spin blood
liquid
separate into 2 parts
(3)
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
part of the cardiovascular system
(heart, vessels)
provide nutrients, O2, chemical messages
removes wastes
provide protection
to/from/for all the cells of the body
Blood Overview
•transport:
dissolved gases
nutrients
hormones
wastes
•regulate:
ionic composition and pH
of body fluids
Blood Overview
•restrict fluid lose at injury
•defend against toxins and pathogens
•stabilize body temperature
Blood Overview
•restrict fluid lose at injury
•defend against toxins and pathogens
•stabilize body temperature
Blood Overview
plasma
~55% of blood
H 2O
plasma proteins
ions
nutirents
wastes
hormones
92%
7%
Blood Overview
formed elements
produced through hemopoiesis
99.9%
0.1 %
RBC’s
WBC’s and platlets
Blood Overview
whole blood
•38˚ C
•5x more viscous than H2O
(sticky, thick)
•slightly alkalai
pH 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 vein
venipuncture
easy to find
thin walls than arteries
lower bp than arteries
Clinical Note
capillary blood
finger tip
earlobe
toe / heel (infant)
small quantity (drops)
Clinical Note
arterial blood
radial or brachial artery
check blood gases
Stop here 3/21
Lec #29
Blood plasma
body fluids
ICF
ECF
interstitial fluid
blood 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
proteins:
7.6 g% (5x ICF)
7.6 grams / 100 ml plasma
large size and globular shape
prevents them from leaving vessels
three classes of proteins:
albumins
globulins
fibrinogen
Blood plasma
proteins:
albumins
60% of plasma proteins
made in liver
transport:
fatty acids
hormones
other stuff
Blood plasma
proteins:
globulins
35% of plasma proteins
two types
immunoglobulins
aka., antibodies (Ab)
transport globulins
hormone-binding
(thyroid H)
metalloaproteins
(iron)
apolipoproteins
(lipids)
steroid-binding
(testosterone)
Blood plasma
proteins:
fibrinogen
4% of plasma proteins
blood clotting
converted to fibrin (strings)
(framework for clot)
plasma without clotting stuff
= serum
Blood plasma
proteins:
other plasma proteins
various
hormones
origins of proteins
liver 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 solutions
short-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’s
aka.,red blood cells
erythocytes
contain pigment molecule hemoglobin
Hb + O2
(dark)
HbO2
(bright red)
RBC’s
Quantity
# RBC’s in one µl (microliter)
(1 mm3)
about 5,000,000 cells / µl
x 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 males
42 females
RBC’s
Quantity
What factors may affect the
hematocrit ?
increase
dehydration
EPO stimulation
decrease
bleeding
problems with RBC production
RBC’s
Structure
unusual cells
lack 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 divide
cannot synthesize proteins
cannot 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 structure
4 polypeptide chains
2 alpha (a) chains
2 beta (b) chains
(amino acids)
each chain has a heme
pigment moleucle
Fe2+
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 Hb
carbaminohemoglobin
RBC’s
Structure of Hemoglobin
low hematocrit
low 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 stress
cannot repair themselves
macrophages
engulf old/damaged cells
engulf cell parts after hemolysis
RBC’s
Formation / Turnover
hemolysis
releases Hb from cells
if phagocytosed - recycled
if not, eliminated by kidney
hemoglobinuria
red or brown urine
lots of Hb in urine
RBC’s
Formation / Turnover
hemolysis
hemoglobinuria
hematuria
intact RBC’s in urine
means kidney damage or
blood vessel damage
RBC’s
Formation / Turnover
recycling (by macrophages)
globin proteins
amino 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 marrow
by transferrin
used to make new RBC’s
need 26 mg/day
1-2 mg is usually enough
most is recycled
RBC’s
Formation / Turnover
recycling
too little Fe2+
reduction of RBC production
dietary deficiency
iron absorption
iron-deficiency anemia
RBC’s
Formation / Turnover
recycling
too much Fe2+
excessive buildup in heart
linked to heart disease
excessive buildup in liver
fig. 19-4
to here 3/23
lec # 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
erythropoiesis
embryo yolk sac
fetusliver, spleen
adults
red bone marrow
(aka., myeloid tissue)
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 acids
iron
vitamins
B6
folic acid
B12
meat/dairy products
absorption requires
intrinsic factor
RBC’s
Regulation of Production
requirements:
B12
if not enough eaten
or absorbed
pernicious anemia
RBC’s
Regulation of Production
stimulated by EPO
erytropoietin
erythropoiesis stimulating hor.
made by peripheral tissues especially
kidney when exposed to low oxygen
levels
hypoxia
RBC’s
Regulation of Production
what might trigger kidney
to release EPO?
anemia
reduced blood flow to kidney
low O2 in lungs
(disease or high altitude)
lung damage
RBC’s
Regulation of Production
effects of EPO
stimulates cell division in
erythroblasts and stem cells
stimulates Hb synthesis and
maturation of RBC’s
RBC’s
Regulation of Production
effects of EPO
RBC production can
increase 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 thicker
strain 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
cells
(including RBC’s) have
proteins on their surface
antigens
“foreign” molecules
can trigger immune response
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
A
B
Rh
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
DOMINANT
recessive
IA IA
IA i
IB IB
IB i
IA IB
ii
A
A
B
B
AB
O
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
Ab + RBC
agglutination
and hemolysis
cross reaction
blood transfusion
test for
compatability
Blood typing
standard test
determine donor’s and
recipient’s blood type using
ABO and Rh systems
mix drops of blood with
anti-A
anti-B
anti-Rh
A+
B+
AB+
Ofig. 19-7
universal
donor
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 blood
and look for problems
Blood typing
HDN
Hemolytic disease of the newborn
Blood typing
HDN