Transcript blood - SCHOOLinSITES

BLOOD
FUNCTIONS OF BLOOD:
Transport nutrients
 Transport oxygen
 Transport wastes
 Transport hormones
 Helps maintain the stability of the
interstitial fluid
 Distributes heat
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General Description:
Connective tissue
 Blood solids: RBC’s, WBC’s, and platelets
 Liquid matric: plasma
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“Formed Elements” of blood:
Red Blood cells
 White blood cells
 Platelets
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Blood Plasma:
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Liquid portion
Centrifuged Blood Sample:
Buffy Coat
Blood Volume:
Varies with body size
 Varies with changes in fluids and
electrolytes
 Depends on amount of adipose tissue
 Average size adult: 5.3 quarts or 5 liters
 Men have more blood than women
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Blood Composition
45% formed elements (hematocrit)
 55% plasma (mixture of water, amino
acids, proteins, carbohydrates, lipids,
vitamins, hormones, electrolytes, cellular
wastes)
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Erythrocytes: RBC’s
1/3 hemoglobin
(protein that carries
Oxygen)
 Extrude nucleus as
they mature
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Hemoglobin:
Oxyhemoglobin:
bright red
 Deoxyhemoglobin:
dark red
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Red Blood Cell Counts
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Range for adult males:
4,600,000-6,200,00 cells per mm3
Range for adult females:
4,200,000-5,400,000 cells per mm3
Why are RBC counts used as routine health
checks?
Red Blood Cell Production
(Hematopoiesis):
Before birth: yolk sac, liver, spleen
 After birth: red bone marrow
 AVERAGE LIFE SPAN: 120 days
 The hormone erythropoietin (from liver
and kidneys) controls the rate of RBC
production.
 Kidneys and liver release eruthropoietin in
response to oxygen deficiency.
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Negative
feedback
system
Erythropoitin
Bone
Dietary factors affecting RBC
production:
B complex vitamins: B12 and folic acid
 Iron: makes up Heme in hemoglobin
 Anemia: too few RBC’s
 Hemochromatosis: too much iron
absorpton; irons builds up to toxic levels
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Destruction of RBC’s
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Macrophages (WBC) phagocytize and destroy
damaged RBC’s primarily in the liver and spleen
Hemoglobin is broken down into heme and
globin
Heme is decomposes into iron and biliverdin
(green pigment)
Iron will be reused by red marrow to make more
RBC’s
Biliverdin is converted to bilirubin and is
excreted in bile
White Blood Cells: Leukocytes
Protect against disease
 Development: Fg. 12.4 p. 306
 Development is controlled by:
interleukins and colony-stimulating
factors (CSF’s)
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WBC’s:
Differ in size
 Differ in cytoplasm (granulocytes &
agranulocytes)
 Differ in shape of nucleus
 Differ in staining characteristics
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5 Types of WBC’s: Divided into 2
groups:
Granulocytes: neutrophils, eosinophils,
basophils
 Agranulocytes: monocytes & lymphocytes
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Granulocytes:
Twice the size of a RBC
 Develop in red bone marrow
 Short life spans (about 12 hours)
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Neutrophil:
Light purple granules
in cytoplasm (neutral
stain)
 Lobed nucleus w/ 2-5
sections
 Make up 54-62% of
WBC’s in adult blood
sample
 Phagocytize small
particles
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Eosinophils:
Bi-lobed nucleus
 Cytoplasmic granules
stain deep red in acid
stain
 Make up 1-3% of
circulating WBC’s
 Kill parasites; help
control inflammation
& allergic reactions
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Basophils:
Bi-lobed nucleus
 Cytoplasmic granules
stain blue in basic
stain
 Make up less than 1%
of circulating WBC’s
 Release heparin &
histamine
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Granulocytes Review:
Eosinophil
Neutrophil
Basophil
Agranulocytes:
2 types: monocytes & lymphocytes
 Monocytes arise from red bone marrow
 Lymphocytes differentiate in the red bone
marrow and the organs of the lymphatic
system
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Monocytes
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Largest blood cells (23 x’s larger than RBC)
Nuclear shape varies
from spherical to
lobed
Make up 3-9% of
circulating WBC’s
Phagocytize large
particles
Live weeks to months
Lymphocytes
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Slightly larger than a
RBC
Large, round nucleus
Make up 25-33% of
circulating WBC’s
Live for years
Provides immunity
Functions of WBC’s
Some phagocytize
 Some produce antibodies
 Leukocytes can squeeze out through the
capillary wall and enter the tissue spacethis is called diapedesis
 Neutrophils & monocytes are the most
mobile and active phagocytic WBC’scontain a lot of lysosomes
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Cont.
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Eosinophils are weakly phagocytic
Eosinophils can kill certain parasites
Eosinophils help control inflammation and
allergic reasions
Basophils release heparin (helps blood clot) and
histamine (increases blood flow to injured
tissue) Also play a role in allergic reactions.
Lymphocytes are important in immunity-some
release antibodies
White Blood Cell Counts
WBCC is normally 5,000-10,000 per mm3
 An increase could mean infection
 Above 10,000 acute infection
(leukocytosis)
 Below 5,000 is called leukopenia (flu,
measles, mumps, chickenpox, AIDS, polio)
 DIFF (differential WBCC) Percentages of
different types of white blood cells
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Platelets (Thrombocytes)
Not complete cells-no nucleus
 Half the size of a RBC
 Lives about 10 days
 Arise from megakaryocytes in red bone
marrow
 Megakaryocytes develop from
hematopoietic stem cells in response to
the hormone thrombopoietin
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Platelets
Help form blood clots
 Platelet Count:
 130,000-360,000 per
cm3
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Blood Plasma
Plasma proteins are the most abundant of
the solutes in plasma.
 Three main plasma protein groups:
albumins, globulins, and fibrinogin
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Albumins
Smallest of the plasma proteins
 Make up 60% of proteins by weight
 Make in liver
 Important determinant of osmotic
pressure-regulate blood volume
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Globulins
Make up 36% of plasma proteins
 Alpha, beta, and gamma globulins
 Liver makes alpha and beta (transport
lipids and fat-soluble vitamines)
 Lymphatic tissue makes gamma globulins
which are a type of antibody
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Fibrinogen
Makes up about 4% of plasma proteins
 Helps in blood coagulation
 Made in the liver
 Largest of the plasma proteins
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Plasma Gases:
Oxygen
 Carbon dioxide
 Nitrogen (no physiological function)
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Plasma Nutrients:
Amino acids
 Simple sugars
 Nucleotides
 Lipids (triglycerides, phospholipids,
cholesterol) most combine with proteins to
form lipoproteins
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Lipoproteins are classified on the
basis of their densities:
VLDL-very low density lipoproteins: high
concentration of triglycerides
 LDL-low density lipoproteins: high
concentration of cholesterol
 HDL-high density lipoproteins: high
concentration of protein and lower
concentration of lipids
 Chylomicrons: transport dietary fats to
muscle and adipose tissue
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Nonprotein nitrogenous substances
in plasma:
Amino acids (breakdown of protein)
 Urea (breakdown of protein & nucleic
acids)
 Uric acid (breakdown of protein & nucleic
acids)
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Plasma Electrolytes:
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Sodium
Potassium
Calcium, magnesium
Chloride
Bicarbonate
Phosphate
Sulfate
**sodium & chloride are the most abundant
Hemostasis
Stoppage of bleeding
 Involves:
1. blood vessel spasm
2. platelet plug formation
3. blood coagulation
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Blood Vessel Spasm:
Breaking a blood vessel stimulates the
smooth muscles to contract (vasospasm)
which lessens blood loss
 Last anywhere from a few minutes to
about 30 minutes
 Platelets release serotonin which contracts
smooth muscles in the blood vessel walls
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Platelet Plug Formation:
Platelets stick to each
other, to the end of
the broken vessel,
and to exposed
collagen
 The platelet plug
helps control blood
loss
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Blood Coagulation:
Formation of a blood
clot
 Involves clotting
factors (some
promote clotting
others inhibit)
 Soluble fibrinogen is
converted to insoluble
fibrin (RBC’s become
trapped)
 Fg. 12.16 p. 316
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Prothrombin in the
 Serum-clear to yellow
presence of Ca ions is
liquid that remains
converted to thrombin
after the clot forms
(plasma minus
 Thrombin initiates a
clotting factors)
reaction the cuts
fibrinogen into pieces  Fibroblasts invade clot
of fibrin
and help strengthen
and seal the vascular
breaks
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Thrombus vs Embolus
Thrombus-blood clot that forms
abnormally in a blood vessel
 Embolus-clot that dislodges and is carried
away by blood; can lodge and prevent
blood flow
 Both are often associated with
atherosclerosis (fat deposits in arteries)
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Agglutinaton
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Clumping of RBC’s following a transfusion
reaction
Antigens vs Antibodies
Antigens: proteins on the surface of RBC’s
 Antibodies: proteins that react with the
antigens
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ABO Blood Group
UNIVERSAL DONOR: TYPE O
 UNIVERSAL RECIPIENT: TYPE AB
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Rh Blood Group
Rh + (Rh antigen on surface of RBC’s)
 Rh – (Rh antigen not present on RBC’s)
 If Rh – receives Rh+ Anti Rh + antibodies
are made that will clot the blood
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Rh Incompatabiltiy:
Rh – Mother
 Rh + father
 If baby is
Rh + like father
Mom becomes
Sensitized
Second Rh +
Pregancy-babies
RBC’s can be
destroyed
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