The Physiology of Blood: 1/25 and 1/27
• Chemical composition of plasma
• Lipoproteins: Good, Bad and Ugly
• Types of leukocytes
• What does hemoglobin look like?
• How does “cooperativity” ensure that hemoglobin is either 100%
saturated with oxygen or 0% saturated?
• WHY is it important for a fetus to have Hb that are different from adult
Hb?
• How does oxygen binding by hemoglobin change during exercise? Why
is this so beneficial?
• What particles do we find in blood besides the “formed elements”?
• Why are lipoproteins needed to move lipids in the blood?
• Which lipoproteins are termed “Good” and “Bad”?
• How are red blood cells typed with the ABO and Rh Systems?
• What are the primary leukocytes and what is a differential blood count?
• What is the specialized function of each type of WBC?
What is the relative size of the materials in blood?
Each erythrocytes contains about
380 million molecules of oxygen
carrying hemoglobin (4 O2/Hb).
PLASMA PROTEINS HAVE VARIED SIZES, WEIGHTS AND
FUNCTIONS. WHILE THEY MAY NOT BE PRESENT IN LARGE
AMOUNTS, THEY ARE CRITICAL FOR OUR HEALTH.
Liver produces about 4 grams plasma protein/hour.
…..But not the gamma globulins
• Albumin: 60%- “Pickup truck of the human body”
• Plasma Globulin Types 36%: -, -, and • Fibrinogen 4%> Fibrin> Cross-linked Fibrin>Firm Clot
Serum is plasma that has had the fibrinogen removed!
• Plasma proteins influence drug availability• What would happen to blood viscosity in a person who has
chronic blood loss and anemia from a stomach ulcer and liver
failure?
WHAT HEALTH CONSEQUENCES COULD CHANGES IN
PLASMA AND/OR BLOOD VISCOSITY HAVE TO A PERSON?
• Plasma and blood viscosity relative to water• PCV, disease and cardiac workloadDo “blood thinners” really change “viscosity”?
What happens to plasma viscosity after a diuretic?
• Osmotic pressure of the protein in the plasma creates an effect
that pulls fluid from the interstitium into the plasma- Kwashiorkor, Ascites, and dietary protein deficiency
What causes the pot-bellied appearance as child nears
death?
• Viscosity and clotting during severe dehydration:
– Why does gangrene often occur in the limbs of a diabetic?
• What happens to blood viscosity during severe frostbite?
Why does gangrene often result?
Lipoproteins and the similar Chylomicrons have an outer
phospholipid layer with special proteins facing the water and
variable lipid contents on the inside. These small particles help
you move lipids between locations in the body.
What particles carry fats in our bodies?
Chylomicrons: largest and synthesized in the intestine.
Carry_____________from the _______to the ________
Very Low Density Lipoproteins: VLDL: Big and synthesized by
liver. Carry_______from the _______to the _________
Low Density Lipoproteins: LDL: VLDL-left over!
Carry__________from the _______to the ______________
High Density Lipoproteins: HDL: smallest and synthesized by
liver. Carry________from the _______to the ____________
WHY is HDL called “Good Cholesterol” and LDL “Bad
Cholesterol”
Plasma cholesterol and coronary heart disease/stroke risk:
• Dietary influence and Genetic Influence:
Why do we often die of a heart attack a few hours after a fatty
Christmas dinner? Look and see next Wednesday!
Can you predict the highest risk days for a thrombosis
leading to a heart attack or stroke based on diet?
What to know about the five white blood cell (leukocyte) types?
1) ID by appearance, 2) ID by function, 3) Relative frequency
Granulocytes: grainy cytoplasm
Agranulocytes: clear cytosol
Neutrophil: common (45-70%)
Lypmphocytes: common 20-40%
• Nucleus: sausages on a string!
Small cell with big round nucleus
• Phagocytic
B-cell:makeAbs against Antigens
• Count increased in presence to T-cell and Nat. Killer Cell:Handle
fight bacterial infections
Ags
Eosinophil: uncommon (1-5%)
Monocytes: (become macrophages)
• Red/pink cytosol color
are slightly common 3-10%
• Phagocytose Ab-Ag, makes
Clear cytosol/bean-like nucleus
defensive enzymes, allergies and Become macrophages when mature
inflammation
Migrate in response to signals
• Indicator of gut parasites
Basophil: purple and rare(0.1-5%)
Don’t Forget RBC: no nucleus: for
• Secrete histamine-dilator
gas transport MOST COMMON
• Secrete heparin-block clotting
Platelet: Cellular fragments that
• Intensify allergic response
mediate hemostasis
Leukopenia: “low WBC numbers: under 5,000/ul”
Leukocytosis: “high WBC numbers: +10,000/ul”
Differential Counts: # of each WBC as % of total WBC count
Hematopoeisis: make new RBCs Leukopoiesis: make new WBCs
Leukemia: WBC Cancer
• Myeloid Cancer:
granulocytes
• Lymphoid Cancer:
agranulocytes
• Chemotherapy often
results in a fatal
opportunist infection in
patient! Because no
replacement WBCs are
available when infection
is encountered.
Blood is composed of
fluids (plasma/serum)
and formed elements
(erythrocytes,
leukocytes and
platelets)
Percent (%) of blood
volume filled with
formed elements is
called Hematocrit or
Packed Cell Volume
(Hct% or PCV)
Average for male:
47%
Average for female:
42%
Hematocrit (Hct%) or
Packed Cell Volume (PCV)
Calculations:
Total tube volume 100 ml, with
25 ml formed elements and
75ml plasma: Hct=25%
-”Anemic”
Total tube length 50mm, 20 mm
formed elements (30mm
plasma):Hct=40%
-”Normal”
Total tube volume 60 ml, with
40 ml formed elements and
20ml plasma: Hct=60%
-”Excess RBCs”
Hemoglobin consists of 4 protein subunits (globins) and each
globin has a heme at its center. Each heme holds a single Fe++
and can hold a single O2 molecule (4 O2 /hemoglobin).
There are about 380,000,000 hemoglobins in each erythrocyte!
Each erythrocyte can carry up to about 4X380,000,000 oxygens!
Hemoglobin has 4 globins, 4 hemes, 4 Fe++,
and binds up to a maximum of 4 O2 (or No O2 at all)
The protein subunits are called “globins”
Two can be “alpha” in adult or fetus
Two can be “beta” in adult-appear just before birth
Two can be “gamma” in fetus-lost right around birth
The “HEME” is a ring like structure that has Fe++ in the
center. Oxygen is attracted to the Fe++ that binds it
temporarily and releases it later where needed.
Attachment and release is determined by concentration
gradients (What are gradients in LUNG or HEART?)
Oxygen tends to fall of the heme if there is little oxygen
around the heme….so oxygen is then supplied to tissues.
Oxygen binds to the heme when there is plenty of oxygen
available and none is attached to the heme…this condition
occurs when erythrocytes are in the capillaries that line the
alveoli of the lung.
“Cooperativity” describes how the four globins of
hemoglobin interact with each other and oxygen.
When all 4 hemes are without oxygen (empty) affinity is low, but
gradient is high.
The binding of oxygen to any one heme affects the remaining
three and makes them more likely to bind oxygen.
When another oxygen binds, it makes the remaining two even
more likely to bind oxygen.
Binding of a third oxygen tremendously increases the affinity of
the last empty heme to find and oxygen.
Assuming an oxygen can bind the heme, the hemoglobin is now
filled (100% saturated) with oxygen.
INVERSE: When any single heme in the hemoglobin looses an
oxygen, the other three are more likely to lose an oxygen, etc…
Net Result? Hemes want to be completely filled with oxygen or
completely empty! This gives the binding curve a “sigmoid” shape.
This is HUGELY important physiologically!
Myoglobin in muscle has one heme and globin (No Cooperativity).
Hemoglobin in a erythrocyte has four hemes and globins.
Why do the oxygen binding characteristics of these two proteins
look so different? Hyperbolic vs. Sigmoid Curve
Oxygen is
bound to
almost
100% of
available
Hb-hemes
in the lung.
1) Oxygen is removed from the hemoglobin
2) Percent saturation reduced (oxygen used).
Hb has “Cooperativity”--------- Mb has NO “Cooperativity”!
Why would you want fetal hemoglobin (2 gamma subunits) to bind
oxygen much more tightly than adult hemoglobin? Is there more oxygen
in the blood of the fetus or the mother? Like all molecules oxygen can
only diffuse down concentration gradients in the body.
DANGER! Carbon monoxide has an extremely high affinity for Hb
(Hb-CO), so oxygen cannot bind Hb in the lung!
The Bohr Effect is amazing!
Acids accumulate ( ↓pH) in metabolically active tissues!
This is a signal that oxygen needs have increased in the tissue!
If oxygen needs increase, oxygen delivery needs to increase! HOW IS
THIS DONE?
Protons (H+ or acids) are a signal that cause the hemoglobins to DUMP
their oxygen in acidic tissues that should also be hypoxic!
The Bohr Effect says that as conditions become more acidic (even
slightly) the hemoglobin is more likely to release its oxygen.
The reverse can also occur…..remember hyperventilating as a kid?
This causes your blood pH to become alkaline and you pass out because
you have plent of oxygen in the blood, you cannot remove the oxygen
from your hemoglobin properly in your brain!
The shift in the oxygen binding curve to the right means less oxygen
will be attached to the hemoglobins in acidic conditions! (high O2use)
So oxygen leaves hemoglobin and is delivered to where it is needed
most! ↑Carbon dioxide and ↑Temperature have similar effects.
If the Hb is not bound by oxygen you will appear cyanotic (bluish)!
Remember that only a tiny amount of oxygen can dissolve directly in
blood! (see bottom yellow line) The more hemoglobin you have in
your blood, the more oxygen your blood can deliver (that simple)!
If the tissues are warmer or more acidic, the oxygen is more likely to
leave the hemoglobin so it can be used in this tissue (that simple).
Shift occurs if pH↓ or Temp. ↑
What are the characteristics used to describe blood and the
erythrocytes that contain the oxygen carrying hemoglobin? For
lect/lab exam be able to interpret MCV, MCH, MCHC and MCD.
Content for Lecture Test #1 Stops here
50 points: 46 multiple choice questions + 4 written pts + 2 pt
extra credit The rest of this material will be on test #2
“Let the notes be your guide to what is most important and most
likely to appear on the exam”….but ya cannot do it without reading
the book and comparing notes to book.
Look at questions in back of chapter
Look at practice quiz questions
Create your own study guide an exam questions from your
notes
Practice test is ONLY to help you understand test format….it is
NOT a “study guide”.
Bring a CLEAN scantron (50 que/ half sheet)….Write written
questions anywhere you want ON BACK OF SCANTON
Double check your bubble answers for smears, mistakes, etc.
What you hand in is what is graded, instructor will not correct for
poorly erased, partially filled bubbles, or other errors.