Blood lab answers

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Anatomy and Physiology I
Lab: Blood
Blood is the fluid that circulates through the heart, arteries, capillaries and veins and that
constitutes the chief means of transport within the body.
Blood is a _liquid_connective __ tissue.
A) Three General Functions of Blood:
1. _Transportation______
The blood transports:
- _oxygen____________ from the lungs to the cells of the body
- _CO2_________ from body cells to the lungs
- _nutrients_____________ from GI tract to body cells
- _hormones____________ from endocrine cells to other body cells
- _heat_________ and _waste_________ products to lungs, kidneys and
skin for elimination
2. _Regulation___________________
Circulating blood helps maintain homeostasis in all body fluids.
The blood helps:
- __regulate pH_____________ through buffers
- adjust body __temperature_____________
- influence __H2O________ content of cells
3. _Protection_______________________
The blood:
- protects against its _excessive loss__ after and injury via _clotting___
- protects against _disease____________ via –
a. phagocytic white blood cells
b. blood proteins (antibodies and interferons)
B) Major Components of Blood
1. Components
a) _blood plasma_______________
- a watery liquid matrix that contains dissolved substances
b) formed elements = _cell and cell fragments_____
i) _red blood cells__________ (erythrocytes) (RBC)
ii) _white blood cells________ (leukocytes) (WBC)
iii) _platelets_________________
2. Total Blood Volume of RBC, WBC and platelets and plasma
Complete the labels below.
a) _plasma_______________55%
b) _cells_______________45%
 99% RBCs
 less than 1% WBCs and platelets
3. Plasma – Composition
a) _water____________ (91.5%)
- liquid portion of blood
- acts as a solvent and suspending medium
- absorbs, transports, releases heat.
b) _proteins____________ (7%)
- those confined to blood stream = _plasma proteins_______
- help maintain proper blood osmotic pressure
3 main plasma proteins
1. _albumin_______ – transport hormones and fatty acids
2. _globulins_______– transport iron, lipids, vitamins
immunoglobulins (antibodies)
- help attack _viruses and bacteria____
3. _fibrinogen_____ – role in blood clotting
c) _other solutes________ (1.5-2%) - electrolytes, nutrients, hormones,
gases, wastes
4. __Red Blood Cells_______________ (Erythrocytes)
a) Structure
RBCs :
 are biconcave _discs_________ which provides a _large surface
area____ for diffusion of gas molecules in and out of RBC

have a __strong flexible plasma membrane____________which allows
RBC to squeeze through narrow capillaries without being damaged

have no _nuclei_____ or _organelles________ therefore all internal space
is available for _O2______ transport and they do not undergo cell division

-
contain protein called _hemoglobin_______________ that
carries O2
gives blood its red colour
b) What is the normal RBC count: male- 5.4 million/drop
female- 4.8 million/drop
c) Hemoglobin
(Can carry _4___ oxygen molecules from lungs to tissue cells.)
Consists of:
i) a _globin_________ protein consisting of 4 polypeptide chains
ii) 4 _heme groups____________
- one heme group is attached to each polypeptide chain
- each heme group contains a _iron ion (Fe2+)___hat can combine
reversibly with one oxygen molecule
-1/3 of cells weight is hemoglobin
d) Hematocrit = _% of total blood volume occupied by RBC_____
- female normal range = __38-46% (avg.42%)____________
= 42% of blood volume composed of
RBCs
- male normal range = _40-55% (47%avg.)__________
(higher since testosterone in males)
i) A higher than normal hemocrit = _anemia____________
ii) A lower than normal hemocrit = __polyethemia_______
e) Blood doping:
What is blood doping?
-injecting previously stored RBC’s before an athletic event
i.
ii.
Why do athletes do it?
-more cells available to deliver oxygen to tissues
iii. Is it dangerous and if so why?
-yes- increases blood viscosity
-forces heart to work harder
C) Transport of O2 and CO2 by RBCs
a) Briefly describe the transport of O2 and CO2 by RBCs.
 Each hemoglobin molecule picks up 4 O2 molecules from the lungs
 Each O2 is bound to the iron of the heme group
 As blood flows through the capillaries the iron-oxygen reaction
reverses. Hemoglobin releases O2 which diffuses into the interstitial
fluid and then into the cells.
 Blood flows through tissue capillaries picking up CO2 which
combines with AAs in the globin part of the hemoglobin.
 As blood flows through the lungs CO2 is released from the
hemoglobin and then exhaled.
b) What does the hemoglobin transport that helps to regulate blood pressure?
-transports nitric oxide and super nitric oxide helping to regulate BP
c) Nitric oxide causing _vasoconstriction_________-is released in the lungs
d) Super nitric oxide causing _vasodilation________-is picked up in the lungs
D) White Blood Cells (Leukocytes)
 White blood cells have a _nucleus____and does not contain _hemoglobin____.
 Granular or agranular classification based on presence of cytoplasmic granules
made visible by staining
Complete the chart below to name and describe the 5 types of leukocytes.
Type of Leukocyte
Function
neutrophil
-phagocytosis – destruction of bacteria
-60-70% of circulating WBCs
-fastest WBC getting to tissue
-granular
destruction due to bacteria
-diameter is 10-12 microns
basophil
-less than 1% of circulation WBCs
-granular
-diameter is 10-12 microns
-involved in allergic reactions –
intensifies the overall inflammatory
response (liberates histamine)
-heighten inflammatory response
eosinophil
-2-4% of circulation WBCs
-granular
-diameter is 10-12 microns
-combat the effects of histamine in
allergic reactions - phagocytosis
-slows down inflammation caused by
basophils
monocyte
-3-8% of circulating WBCs
-agranular
-largest WBC in circulation – diameter is
12-20 microns
-phagocytosis
-takes longer to get there, but come in
larger numbers and destroy more
microbes
-clean up dead tissues following an
infection
B cells- destroy bacteria and inactivate
their toxins- develop into plasma cells,
which produce antibodies
lymphocyte
-20-25% of circulation WBCs
-increase in # during viral infections
-agranular
-small cells 6-9 microns in diameter
-large cells 10-14 microns in diameter
T cells- attack invading viruses, cancer
cells, and transplanted tissue
cells(doesn’t recognize the cells)
Natural killer cells- attack a wide variety
of infectious microbes and certain
spontaneously arising tumor cells
Emigration and Phagocytosis in WBCs
a) How does WBC get between cells?
-WBC roll along endothelium, stick to it & squeeze between cells
b) How do selectins help with emigration
-help WBCs stick to endothelium, displayed near site of injury
c) What role do neutrophils (integrins that are found on neutrophils) play in emigration?
-assist in movement through wall
d) Neutrophils and macrophages(derived from monocytes) _phagocytize__bacteria.
E) Platelets – Hemostasis – a sequence of responses that stops bleeding
a) Structure
-disc shaped cell _fragments_____ with no _nucleus__________
b) Function
i) _help stop blood loss from damaged blood vessels by forming a
platelet plug
ii)_granules of platelets contain substances that promote blood clotting
c) What is vascular spasm?
-damage to blood vessel stimulates pain receptors
-reflex contraction of smooth muscle of small blood vessels
d) What are the steps in order for platelet plug formation briefly explain each step:
(page 647)
1.__platelet adhesion___________- platelets stick to exposed collagen(
damaged blood vessels) underlying damaged endothelial cells in
vessels wall
2.__platelet release reaction______- adhesion causes platelets to
become active
– extend projections to make contact and interact
with each other – liberate contents in vesicles activating nearby
platelets which in turn function as vasoconstrictors, causing
contraction of vascular smooth muscle, which decreases blood flow
through the injured vessel
3.__platelet aggregation_________- vesicle contents makes other
platelets (new recruits) in the area sticky – cause platelets to adhere
to originally activated platelets causing a gathering of platelets
(aggregation), the accumulation and attachment of large numbers of
platelets form a mass called a platelet plug
(platelet plug becomes tight when reinforced by fibrin threads
formed during clotting) – edges of damaged vessel are pulled
together
Blood clotting – through a sequence of events enzyme thrombin
converts fibrinogen to fibrin that forms the threads of the clot
e) What is the role of Vitamin K in Clotting?
-required for the synthesis of clotting factors
f) Intravascular clotting:
i.
What is a thrombosis?
-clot (thrombus) forming in an unbroken blood vessel
ii.
What is an embolus?
-clot, air bubble or fat from broken bone in the blood – pulmonary
embolus is found in lungs
iii.
What can help to reduce inappropriate clot formation?
-low dose aspirin reduces inappropriate clot formation
iv.
What are some diseases caused by these inappropriate clots?
-strokes, TIA (transient ischemic attacks), and myocardial infarctions
F) ABO Blood Groups
a) Define:
i) Antigen = a molecule typically found in the surface of a cell
whose shape triggers the prod’n of Abs that will bind to the
molecule
ii) Antibody = a protein molecule produced by the immune
system that recognizes a particular foreign antigen and
binds to it
b) The ABO blood groups are based on two glycolipid antigens called _A__ and
_B___found on RBCs.
c) - People whose RBC have only antigen A have type __A____blood.
- People whose RBC have only antigen B have type __B____ blood.
- People whose RBC have both antigen A and antigen B have type
_AB_____ blood.
- People whose RBC have neither antigen A nor antigen B have type
_O_______ blood.
d) Blood plasma usually contains antibodies (agglutinins) to the above antigens.
i) Anti-A Antibody reacts with __antigen A__________
ii) Anti-B Antibody reacts with __antigen B__________
e) A person’s blood only has antibodies for the antigens that their RBCs lack.
ie. Type A blood = antigen A on RBC
= anti – B Ab in plasma
f) Complete the table below
Antigen on RBC
A
Blood Type
B
B
Antibody in plasma
Anti – B
Compatible Donor/s
A, O
A
AB
A and B
O
Neither A nor B
Anti - A
Neither Anti A
nor anti-B
Both anti-A and
anti-B
B, O
A, B, AB, O
O
g) Which blood type is the universal recipient?
Explain.
-AB is universal recipient
-can receive blood of any of 4 ABO types since plasma has no antiA Abs or anti-B Abs
h) Which blood type is the universal donor?
Explain.
-O is the universal donor
-can donate blood to any of the 4 ABO types since RBC have
neither A nor B antigens
i) What would happen if a person with type B blood received a
transfusion of type A blood?
Explain.
-
donated RBC would hemolyze (burst) = release
haemoglobin = = kidney damage
- Recipient’s type B blood has B antigens on RBC and anti-A
Ab in plasma
- Donor’s type A blood has A antigens on RBC and anti-B Ab
in plasma
1. recipient’s anti-A Abs in plasma bind to A antigens on
donor RBC = hemolysis of donor RBC = kidney damage
2. donor’s anti-B Abs in plasma bind to antigen B on
recipient’s RBC = hemolysis of recipient RBC
(but anti-B Ab are usually so diluted in recipient plasma that significant
hemolysis does not occur)
G) Rh Blood Group
a)
b)
c)
d)
e)
People whose RBC have Rh antigens are designated _Rh+_____
People whose RBC _lack Rh antigens______ are designated RhNormally the blood plasma does not contain anti-Rh antibodies.
Antibodies only develop in what blood type Rh- or Rh+ circle correct answer.
How do they develop? And give examples!
-antibodies develop only in Rh- blood type and only with exposure to
the antigen
-transfusion of positive blood
-during a pregnancy with a positive blood type fetus
f) When a transfusion reaction occurs upon 2nd exposure to the antigen what
condition occurs?
-Rh- person receives Rh+ blood = recipient’s immune system makes
anti-Rh+ Abs that remain in the blood
-If a 2nd transfusion of Rh+ blood is given the anti-Rh+ Abs will bind to
the donated RBC = hemolysis of donated Rh+ RBC
g) Describe the role of Rh incompatibility in hemolytic disease of the
newborn (HDN).
Rh- mother
Rh+ fetus
- at birth a small amount of Rh+ fetal blood enters maternal
bloodstream
- mother’s immune system creates anti-Rh+ Abs which
remain in blood
- 2nd Rh+ fetus
i. maternal anti-Rh+ Ab cross placenta
ii. anti-Rh+ Ab bind to fetal Rh+ RBC = hemolysis
Prevention:
- Rh- mothers receive an injection of anti-Rh+ Ab after
delivery
- anti-Rh+ Abs bind to any Rh+ RBC in maternal
bloodstream
- mother’s immune system does not make any anti-Rh+ Abs
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