Anatomy_and_Physiology_files/Blood and cardio

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Transcript Anatomy_and_Physiology_files/Blood and cardio

How does a vampire get clean? …
…He takes a blood bath!!!
Blood
and The Cardiovascular System
Volume and Composition
Average human adult has a blood volume
of about 5.3 liters.
Varies with size and sex of individual
Sample of blood =
45% cells by volume – called Hematocrit (HCT) or
Packed Cell Volume (PCV)
Types of CellsRed Blood Cells
White Blood Cells
Platelets
Volume and Composition
Other 55% is a clear, straw colored liquid
called plasma.
Plasma components:
 Water
 Proteins
 Amino Acids
 Nutrients
 Electrolytes
 Wastes
Blood
Where does the color come from?
Hemoglobin
True or false? Oxygenated blood is red,
unoxygenated blood is blue.
FALSE!
Oxygenated blood = bright red
Unoxygenated = deep dark red (maroonish)
DQ - Why do blood vessels look blue?
Red Blood Cells
Also called Erythrocytes
Primary function – transport gases to and from
cells
No Nucleus – Why?
Biconcave Shape –Thin in the middle and thick
on the outside.
Why might these be shaped in this way?
Reason #1 – Increases surface area, assisting in
transportation of gases
Reason #2 - places the membrane closer to
oxygen-carrying hemoglobin in the cell.
Reason #3 – Shape allows it to squeeze through
the tiny capillaries.
Erythrocytes
What is hemoglobin?
An iron based protein in red blood cells
that transports oxygen and carbon
dioxide.
A single RBC can contain over 250
million molecules
Each molecule can bind 4 oxygen
molecules
White Blood Cells
Also known as Leukocytes
Primary Function = fight disease and
infection
Why would your WBC count increase when
you are sick?
Leukocytosis - elevated WBC count
Leukopenia - abnormally low WBC count
Leukocytes
5 Types (names, amount in mm3, function)
Neutrophils (3000-7000) - phagocytize small
particles
Eosinophils (100-400) - kill parasites, controls
inflammation
Basophils (20-50) - release heparin and
histamine
Lymphocytes (1500-3000) - provides immunity,
fights tumors
Monocytes (100-700) - phagocytize large
particles
Platelets
Also called Thrombocytes
Not necessarily Red Blood Cell fragments
Arise from Megakaryocytes
These fragment, releasing small sections into
cytoplasm
Each platelet:
~ half the size of a RBC
Lack a nucleus
Function in the formation of blood clots
Plasma
92% Water
Functions
1. Transport materials (such as?)
2. Regulate Fluid and electrolyte levels
3. Regulate pH
Components
Plasma proteins
Nutrients and Gases
Plasma Electrolytes
Plasma Proteins
3 Types
Albumins
Smallest in Size, make up 60% of volume
Function – Osmotic Pressure
Why are so many needed?
Globulins
Alpha and Beta – transport lipids and vitamins
Gamma – are a type of antibody
Fibrinogen
Least common plasma protein (4%)
Function – Blood Coagulation
Nutrients and Gases
Includes amino acids, simple sugars, and lipids
Where do these nutrients come from?
How are lipids (not water soluble) able to be in the
plasma?
Lipoproteins
Low density Lipoproteins
High Density Lipoproteins
Which one is good, which is bad?
How do they have different densities?
Plasma Electrolytes
Plasma Electrolytes
Include: Sodium, Potassium, Calcium, Chloride,
and others
Where do they come from?
Large intestine
Electrolyte Purposes:
1. Maintain Osmotic Pressure
2. Supply tissues with electrolytes when
needed
3. Regulate pH
Blood Drop Activity
• As a class, we will be a blood drop, you
will be assigned a specific part of the
blood drop.
• It will be your job to describe your part
without mentioning what you are.
• We will have a class riddle session to
guess the part of blood that each person
is.
Production of a Blood Cell
• Occurs in the red bone marrow
• Can be triggered by different things
– Megakaryocytes – tissue damage
– Leukocytes – foreign invaders
– Erythrocytes – oxygen levels and erythropoietin
• Low oxygen = more erythropoietin (more production)
• High oxygen = less erythropoietin (less production)
• All types start out as a Hemocytoblast (blood stem cell)
• Then differentiates into:
– Lymphoid cells, which become lymphocytes
– Myeloid cell, which will become a leukocyte, erythrocyte or
thrombocyte
Blood Clotting
• Hemostasis – stoppage of bleeding
• Done in three ways
• 1. Platelet plug
– What is this?
• Platelets typically repelled by walls of blood
vessel
• But when wall is broken, collagen is exposed and
the platelets are attracted to and stick to that.
• Platelets then release chemicals to attract more
platelets
– This keeps building, creates a dam.
Hemostasis
• Platelets also release serotonin, this
causes:
• 2. Vasoconstriction
– What is this?
• Muscular layers in the walls of the vessel
contract
– Can sometimes close the vessel completely
– May only last for a few minutes
Hemostasis
• The damaged tissue will release a chemical that
starts the process of:
• 3. Blood Coagulation
– What is this?
• Formation of a blood clot
• This is the most effective, but takes the most
time.
• A chain of events must occur for this to happen
– Prothrombin to thrombin
– Fibrinogen to Fibrin
– Fibrin “net”
• How would anticoagulants affect this?
Hemostasis
• What must happen?
Blood Types
• On our RBCs we have antigens
– Identifiers to let our body know our cells
• Our blood also contains antibodies against
other blood types
– This will attack blood types with other
antigens (ex. Type A has anti-B antigens and
will attack type B cells)
– This will cause agglutination
• This is why blood type is so important
during blood transfusions.
Blood Types
Blood type
Antigens
Antibodies
Possible Donor
types
A
A
Anti-B
A
O
B
B
Anti-A
B
O
AB
A and B
None
AB, A, B, O
O
None
Both
O
O = Universal Donor
AB = Universal Recipient
• There are other factors (Rh factor) that play a
role too but we are not going to worry about those
Blood Types
• The genes for A and B are codominant, the
genes for type O are recessive.
• This means that there are four possible blood
types
• And 6 possible genotypes
•This is useful in eliminating potential fathers in
paternity cases
Blood Type
Possible Genotypes
A
AA
AO
B
BB
BO
AB
AB
O
OO
Parts of the heart
• External Anatomy
• Average - 14 cm long (base to apex)x 9
cm wide and 280 g
• Covered with the Pericardium
– A sac like structure filled with fluid
surrounding the heart.
• Why would this be here?
• Used mainly for protection
• Walls of the heart are thick and muscular
– Why would this be?
Parts of the heart
• Internal Anatomy
• 4 Chambers
• Atria – Blood enters heart here
– From where?
• Body or the lungs
• Ventricles – Blood leaves heart from here
– The walls are much thicker around the
ventricles, why
Parts of the heart
• Atrioventricular valves
– What are they going to do?
• Separate the atria and ventricles
• They prevent blood from flowing the wrong
direction
• Tricuspid valve – between right atrium and
right ventricle
• Mitral valve – between left atrium and left
ventricle
• Also valves at the beginning of pulmonary
veins and aorta
Parts of the Heart
• What would be a problem if the valves
would not working correctly?
– AKA Heart murmur
• Heart becomes inefficient – can cause
complications
*****Sound of the heart beat comes*****
from the valves closing.
Cardiac Cycle
• AKA Heartbeat
• Atrial walls contract while ventricular walls
relax
• Ventricular walls contract while atrial walls
relax
• What valves would close during each of
these processes?
• Atrial contraction = pulmonary and aorta
• Ventricular contraction = Mitral and tricuspid
Path of Blood
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•
•
•
•
•
•
•
•
•
Right atrium 
Right ventricle 
pulmonary artery 
lungs 
pulmonary vein 
left atrium 
left ventricle 
aorta 
body 
vena cava  right atrium
Electrocardiogram (ECG/EKG)
• Records electric impulses in the heart
– Where do these come from?
• 3 parts
• P wave – atrial contraction
• QRS complex – ventricular
contraction
• T wave – ventricular relax.
Blood Vessels
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•
3 types
Arteries
Veins
Capillaries
All of these provide a closed system for
blood to continuously flow through
– But each are structurally and functionally
different.
Blood Vessels
• Arteries
• Carry blood away from the heart at high
pressures
• Characteristics of the walls:
– Strong
– Thick
– Elastic
• Why would the walls have these
characteristics?
Blood Vessels
•
•
•
•
Veins
Designed to carry blood back to the heart.
Run parallel to arteries
Wall is similar in structure to arteries, but
muscular layer is less developed.
– Wall is thinner, weaker, and less elastic
Blood Vessels
• Capillaries
• Smallest of blood vessels
– Some are so small that only a single RBC can
make it through at a time
• Have extremely thin walls
• Why would they have such thin walls?
• This is the point where gases and
nutrients are exchanged.
Blood Pressure
• Measures amount of pressure on large
arteries
• Two numbers (i.e. 120/70)
• First number is systolic pressure
– Amount of pressure when heart is contracting
• Second number is diastolic pressure
– Amount of pressure when heart is relaxed
• Why is high or low blood pressure bad?