BLOOD
February 9-10, 2016
What is the function of blood?
Transports material throughout the body, including:
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Water
Oxygen
Carbon dioxide
Nutrients – glucose, fatty acids, amino acids, vitamins)
Electrolytes
Hormones
Immune cells
HEAT!!
Why can
do we
you
need
die oxygen?
from blood loss?
Lack
We need
of oxygen
oxygen
in to
heart
do cellular
and brain
respiration – to convert glucose
into ATP
What is blood made of?
plasma ~55%,
platelets & white blood cells ~1%,
red blood cells ~44%
Blood Components
Plasma (~55% TOTAL VOLUME)
• ~92% water
• ~7% proteins
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Albumin (osmotic balance)
Fibrinogen (clotting)
Antibodies (immune)
Hormones (regulation)
• ~1% other solutes
• Electrolytes (osmotic and pH
balance, regulating
membrane permeability)
• Nutrients (glucose, fatty
acids, amino acids)
• Oxygen
• Carbon dioxide
Blood Components
Erythocytes (~44% TOTAL VOLUME)
• aka red blood cells
• tiny!
• lack a nucleus, have few organelles
• contain hemoglobin – an iron-
containing protein that reversibly
binds to oxygen (and a small amount
of CO2)
How does the structure of erythrocytes
facilitate their function?
- very
small to fit through small capillaries
- small size and lack of nucleus, most
organelles designed to maximize oxygen
transport
Blood Components
Leukocytes (< 1% TOTAL VOLUME)
• aka white blood cells
Blood is typically stained
with chemicals that bind
to certain proteins to aid
in identification of cells
• fight pathogens (bacteria, viruses, parasites) and cancer
• can leave the blood stream to go to infected tissue – diapedesis
• summoned to damaged areas by chemotaxis, move by ameboid
motion
•
Blood Components
Leukocyte Types
• Granulocytes – contain granules in cytoplasm and unusually shaped
nuclei
a) Neutrophils – most
numerous leukocyte;
phagocytic; abundant
during bacterial
infection
b) Eosinophils –
kill parasitic worms
and increase during
allergy attacks
c) Basophils assist in inflammatory
response
Blood Components
Leukocyte Types
• Agranulocytes – lack granules in cytoplasm and have normal nuclei
a) Lymphocytes –
2nd most numerous;
include B and T cells;
produce antibodies
and attack infected
cells
b) Monocytes –
engulf and destroy
pathogens
Blood Components
Platelets (<1% TOTAL VOLUME)
• cell fragments
•
involved in blood clotting
Review 1: What is blood made of?
Identify each component, and justify your
response!
A
B
C
D
Review 2: Structure & Function
Identify the component of blood that transports each
material, and justify your response!
•
•
•
•
•
•
•
•
Water
Oxygen
Carbon dioxide
Nutrients – glucose, fatty acids, amino acids,
vitamins)
Electrolytes
Hormones
Immune cells
HEAT!!
Review 3: Compare & Contrast
Turn & Talk – 2 min
Compare & contrast the structure and function of
erythrocytes and leukocytes
Hemostasis
Hemostasis is the process of
blood clotting
• Occurs when small blood
vessel (capillary) is damaged
• Clot seals the blood vessel
until the it regenerates
• Occurs in just 3-6 minutes
Process of Hemostasis
Three major events occur, all beginning the moment the
vessel is damaged:
1) Vasoconstriction
2) Platelet plug formation
3) Coagulation of blood
Coagulation takes longer, and
is completed after
vasoconstriction and platelet
plug formation occur
Process of Hemostasis
Watch me!
This is a
simplified
overview of
the clotting
cascade
Hemostasis: Review & Connections
What is the recommended way to treat a bleeding wound (until
you see a doctor)? Why?
Gauze and pressure
The gauze acts much like collagen fibers – provide a rough surface
that helps activate platelets.
Pressure manually constricts blood vessels and also increases the
release of thromboplastin, which helps initiate coagulation.
Never remove gauze or a bandage from an actively bleeding
wound. Why?
Removing the bandage will remove both clotting factors and the
beginnings of a platelet plug or blood clot, causes an increase in
bleeding.
Hemostasis: Review & Connections
How is blood clotting an example of positive feedback?
Which part(s) of the process best exemplify positive
feedback?
(Turn & Talk – 2 min)
Platelet plug formation
Activated platelets release chemicals that cause more
platelets to activate, until a large number of platelets clump
together forming a plug.
Hemostatic Disorders – Blood Clots
A thrombus is a blood clot that forms in an unbroken vessel. A
large thrombus may block blood flow, causing tissue death.
An embolus is a blood clot
that forms then breaks away
and floats freely in the blood
vessels. An embolus may
then lodge in a capillary and
block blood flow.
coronary thrombosis
cerebral embolism –
pulmonary embolism –
Hemostatic Disorders – Blood Clots
A thrombus is a blood clot that forms in an unbroken vessel. A
large thrombus may block blood flow, causing tissue death.
An embolus is a blood clot
that forms then breaks away
and floats freely in the blood
vessels. An embolus may
then lodge in a capillary and
block blood flow.
coronary thrombosis – in heart
cerebral embolism – in brain
pulmonary embolism – in lungs
Hemostatic Disorders – Blood Clots
Causes of thrombus
• Injury to blood vessel or build-up of fatty
plaques
 Both create rough surfaces inside
vessel, which may activate platelets
• Poor blood circulation
 Clotting factors may accumulate
Immobility increases the risk of
deep vein thrombus in legs!
Hemostatic Disorders – Blood Clots
Blood thinners (such as warfarin, aspirin, and heparin) can be
used to prevent thrombus
Aspirin –
blocks thromboxane
reduces formation of platelet plug
Wafarin –
blocks production of certain clotting factors
reduces coagulation interrupting clotting cascade
Heparin –
helps inactivate thrombin
reduces coagulation by preventing conversion of
fibrinogen to fibrin
Review your notes – how exactly does each of these reduce
clotting?
Hemostatic Disorders - Hemophilia
Causes
• lack of one or more clotting factors
• Recessive sex-linked trait (more common in men)
Symptoms
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Prolonged bleeding even from minor injuries
Excessive bruising
Bruised and swollen joints
Excessive clumsiness and falling
Treatment
• Intravenous injection of clotting
factors
• Donated plasma
• Synthetic clotting factors
Hematopoiesis
Hematopoiesis is the process of blood formation.
• Occurs in the red bone marrow
Where is this found?
In babies, nearly all bones have red marrow
In adults, just the flat bones and epiphyses
• All blood cells and platelets derive from hemocytoblast stem cells
Erythrocyte life cycle and production
Develop in red marrow (for 3-5 days)
Eject nucleus, then enter blood stream.
Red blood cells life for 3-4 months
Digested by phagocytes
Production is controlled by
hormone erythropoietin.
Erythropoietin release is
stimulated by low levels of
O2 in blood.
Erythrocyte life cycle and production
Develop in red marrow (for 3-5 days)
Eject nucleus, then enter blood stream.
Red blood cells life for 3-4 months
Digested by phagocytes
Why is there no hormone to
decrease RBC production?
- High numbers of RBCs
don’t cause major
problems
- High levels are temporary.
RBC levels will decline
due to death of cells.
Erythrocyte life cycle and production
Develop in red marrow (for 3-5 days)
Eject nucleus, then enter blood stream.
Red blood cells life for 3-4 months
Digested by phagocytes
Why do world-class athletes train
at high altitude before major
competitions?
-
High altitude has lower
oxygen levels, which
stimulates the production of
erythrocytes
- The high levels of erythrocytes
will persist for a while after
leaving high altitude
Closure
• What were our objectives, and what did you learn about
them?
• What was our learner profile trait and how did we
exemplify it?
• How does what we did today address our unit question?
Exit Ticket
Make mini posters illustrating the following terms.
The posters should
• be in color
• prominently feature the term
• have both a picture
• a definition / explanation of the term
Exit Ticket
Neutrophil
hemostasis
Fibrin
hemophilia
Basophil
Serotonin
fibrinogen
agglutination
Eosinophil
Platelet plug
Platelet factor 3
Albumin
Lymphocyte
Thromboplastin
coagulation
Antibody
Monocyte
Prothrombin
Clotting factor
Antigen
platelet
thrombin
vasoconstriction
Plasma
hemocytoblast erythropoietin
Thrombus
Erythrocyte
hemotopoeisis Prothrombin
activator
embolus
leukocyte