Transcript The Circulatory System and the Blood

RED ALERT!
The Circulatory System and the
Blood
Blood
• Blood is a
heterogeneous mixture.
It is a COLLOID, and
has four main
components
1. Red corpuscles (red
blood cells)
1. White corpuscles (white
blood cells)
2. Plasma (fluid)
3. Platelets
Red Blood Cells
• Carry Oxygen and
Carbon Dioxide with
the help of
Hemoglobin
• They are produced in
the bone marrow
• They live only 3-4
months and have no
nucleus
Blood Types
• Red blood cells will have proteins which stick
out. They are called Antigens
• The opposite of antigens are Antibodies
• If an antigen meets it’s antibody, they clump
and form clots, which are BAD!!
ABO Blood Types
Blood Type
Antigen on red
blood cell
Antibody in
Plasma
A
B
AB
O
A
B
A&B
None
Anti-B
Anti-A
None
Anti-A & Anti-B
Rh antigen: Rhesus
System
• Blood, of all types, can also have an Rh
antigen on them and there is an antibody
for it.
• If a person has this antigen, they will have
a + next to their blood type (ex: A+
means they have the A and Rh antigen)
• If a person does not have this antigen,
they will have a – next to their blood type
(ex: A- means they only have the A
antigen)
Donors & Recipients
• When you are looking at donors and
recipients, you must make sure the
antibodies of the recipient do not attack the
antigens of the donor
• ONLY LOOK AT ANTIBODIES OF RECIPIENT
AND ANTIGENS OF DONOR!!!
• The antibodies of the donor are not
recognized by the recipients body and are
destroyed
• O- is the universal donor and AB+ is the
universal recipient for blood transfusions.
Rh-  Rh+
Plasma
• It carries Nutrients and Hormones
(chemical messages) to the cells
• It carries Urea and Carbon dioxide away
from the cells.
• Plasma suspends red and white blood
cells so they can flow through the body. It
also has:
- clotting factor
- antibodies and
- carries off solid waste.
Platelets
• Smaller than red blood cells
• Responsible for clotting
• Link together to form scabs
when in contact with air.
White blood cells
• They are the main defense
against disease.
• No hemoglobin
• Can pass through capillary
walls.
White blood cells
•
White blood cells kill bacteria and viruses
through:
1) Phagocytosis – eating them with help
from
antibodies
2) Antibodies – Latch onto bacteria/viruses
Pathogens
• Pathogens are viruses and bacteria.
Virus
Smallest pathogen
Bacteria
Single cell organisms
Invade cells
Reproduce quickly
Few drugs to fight
them
Produce toxins which
destroy cells
To kill the virus, you
must kill the cell
Can be killed with
antibiotics
The Circulatory System
• The Circulatory System is the major
transportation system in the body.
Pulmonary
Systemic
circulation
circulation
carries blood that
carries the
contains carbon
oxygenated
dioxide TO THE
blood to cells in
LUNGS, where it
the body and
gets rid of the
supplies them
waste and is
with nutrients as
resupplied with
well.
oxygen
Purpose
• It serves to:
• 1)transport food and
oxygen to the body,
• 2) Pick up waste
produced for removal
from the body,
• 3) Help regulate
body temperature.
The Heart
• This is the motor (pump) that makes the system
work.
Inside the Heart
•
The Heart is made up
of muscle tissue and
has four main
chambers
1. The right atrium
2. The right ventricle
3. The left atrium
4. And the left ventricle
The heart also has
valves to prevent
backflow of blood
The Human Highways
• The “highways” and “roads” of the body
are collectively, they are called blood
vessels. They are:
1)Arteries
2)Veins
3) Capillaries.
Arteries
• Arteries take blood away from the heart.
• Arterioles are smaller arteries.
• They have thick walls and contain a layer of
muscle.
• Blood pumped from the heart is under high
pressure, so it produces small bulges along the
artery.
Veins
• They carry blood to the heart.
• Venules are smaller veins
• They have a thinner muscular layer with lower
blood pressure.
• Surrounding muscles help blood to flow though
veins
• They also contain backflow valves.
Capillaries
• Link Arterioles
to Venules
• Have thin
walls so gas
exchange can
happen.
Blood Circulation
• Right Atrium  Right Ventricle 
Pulmonary Artery Arterioles Pulmonary
capillaries  blood gets oxygenated 
Venules Pulmonary Veins  Left Atrium
 Left Ventricle
• Left ventricle  Aorta  Arterioles 
BODY’s capillaries Venules/Veins 
Vena Cavae (superior or inferior)  Right
atrium
The walls of the left ventricle are thicker (more
muscular) than those of the right ventricle because the
left ventricle has to push blood into the entire body,
whereas the right ventricle only has to push blood as
far as the lungs.
BLOOD ALWAYS LEAVES THE VENTRICLES, GOES
THROUGH THE BODY, AND COMES BACK INTO
THE ATRIUMS!!
Blood Pressure
• Blood Pressure has two types, Systolic and
Diastolic.
• Systolic pressure is measured when pressure
exerted by blood on artery walls is at its
maximum (when the ventricles in the heart
contact)
• Diastolic pressure is measured when pressure
exerted by blood on artery walls is at its
minimum (when ventricles are not contracting)
• Blood pressure = systolic pressure (bigger #)
diastolic pressure (smaller #)
REVIEW: Pressure
• Mathematically, Pressure (symbol: ‘p')
is the force per unit area applied on a
surface.
p= F
A
F= Force
A= Area
The units are N/m2 or Pa or mm of Hg
REVIEW: What is pressure?
• Pressure is the result of molecules or
atoms bouncing off each other and the
surfaces that hold the fluid in.
• So what happens to pressure if
we increase temperature?
• Hint: IT INCREASES!!
So…..
• What happens to pressure if:
– You have a lot of force acting on a small
area?
• High Pressure
– Same force but over a larger area?
• Lower Pressure
– Lower force acting on a huge area?
• Very Low Pressure
Area Formula
What general shape do
you think our blood
vessels are?
They are
Cylinders!
Arteries have a bigger
surface area so that
they can withstand
high force of heart
on blood and
pressure will be
lower
Compressible/Non-compressible
Fluids
• In general fluids (gases and liquids) fit into
two categories.
• Compressible: With increased pressure,
the volume and temperature will change
(decrease).
• Non-compressible: With increased
pressure the volume and temperature will
NOT change (decrease).
• Blood is a non-compressible
fluid
• Fluids move from high pressure to low
pressure area.
• What if the fluid can not pass?
• The blood vessel will burst!
Heart Health
• If blood pressure is to high, you have
Hypertension, to low, Hypotension.
• Hypertension is usually cause by a narrowing
of blood vessels due to cholesterol build up.