Transcript M3 chapter 1

The Circulatory System
The circulatory system includes the Heart, Blood Tissue
and the Blood Vessels.
The Circulatory SystemTransport
• The absorption and
circulation of
materials
throughout an
organism
What does the circulatory system do?
(What is its function?)
1. Delivers food and oxygen to body cells.
2. Carries carbon dioxide and other waste
products away from cells.
 Movement of materials into and out of cells occurs by
diffusion (from an area of high concentration to low
concentration– no energy required)
 Movement also occurs by active transport (from an area of
low concentration to high– this requires energy)
• ** In general, the blood is a fluid tissue
helping to maintain homeostasis for all
cells in the body.
• Transport of needed substances to body
cells. (oxygen, amino acids, glucose,
fatty acids, glycerol, salts, etc.)
The Heart
•
•
•
•
•
Size of your fist
Thick muscular walls
Divided into two pumps
Each pump has two chambers
Upper chamber - atrium receives blood
coming in from the veins
• Lower chamber - ventricle squeezes blood
out into the arteries
Virtual
Body
Parts of the Heart
The heart functions as a double pump
beating in unison.
1. Deoxygenated blood--relatively low in
oxygen
2. Oxygenated blood--relatively high in
oxygen
** Heartbeat is stimulated by an
electrochemical impulse.
Pacemaker - in the right atrium - initiates the
heartbeat
2. Transport of wastes from cells. (urea,
water, carbon dioxide in the form of
the bicarbonate ion)
3. Helps to maintain a constant body
temperature.
4. Aids the body in fighting disease.
Lub
If you listen to
your heartbeat, it
makes a lub dub
sound.
The lub is when blood
is pushed out of the
heart into the body and
the dub is the reloading
of the heart with more
blood ready to push it
out to the body
Dub
Pathway of Circulation
The Heartbeat
• Each heartbeat is called a cardiac cycle.
• When the heart beats, the two atria contract
together, then the two ventricles contract;
then the whole heart relaxes.
• Systole is the contraction of heart chambers;
diastole is their relaxation.
• The heart sounds, lub-dup, are due to the
closing of the atrioventricular valves,
followed by the closing of the semilunar
valves.
How the Heart Works
• The Heart House
To simplify how blood flows
through a normal, healthy
heart, think of the heart as a
house with:
• 4 Rooms (Chambers)
• 4 Doors (Valves)
• 4 Big Hallways
(Vessels)
• 4 Small Hallways
(Vessels)
1. Oxygen-poor blood (shown in
blue) flows from the body into
the right atrium.
2. Blood flows through the right
atrium into the right ventricle.
3. The right ventricle pumps the
blood to the lungs, where the
blood releases waste gases and
picks up oxygen.
4. The newly oxygen-rich blood
(shown in red) returns to the
heart and enters the left atrium.
5. Blood flows through the left
atrium into the left ventricle.
6. The left ventricle pumps the
oxygen-rich blood to all parts of
the body.
The Human (Mammalian) Heart
Structure
1. septum: muscular central wall dividing
the mammalian heart into two halves
2. atria: thin walled upper heart chambers
which receive blood pump blood to the
ventricles
3. Ventricles: muscular thick walled
chambers which pump blood from the
heart -- the lower chambers
4. Valves - prevent the backward flow of
blood in the heart
valve
• flap of tissue that prevents
blood from flowing backward
A = aorta
B = pulmonary arteries
C = pulmonary veins
D = left atrium
E = valve
F = left ventricle
G = right ventricle
H = valve
I = vena cavae
J = right atrium
blood pressure
•caused by force w/
which ventricles
contract
(ventricles contract)
(ventricles relax)
Blood pressure measured w/
sphygmomanometer
blood
vessels
arteries
capillaries
veins
carry blood
away from heart
connect arteries
to veins
carry blood
to heart
aorta=
largest artery
Parts of the Circulatory System
• Divided into three major parts:
– The Heart
– The Blood
– The Blood Vessels
The heart, the lungs, and the
blood vessels work together to
form the circle part of the
circulatory system.
Circulation
• Two parts
• Heart acts as double pump
• Blood from the right side pump is dark red
and low in oxygen (oxygen-poor)
Circulation
• Travels through pulmonary arteries to
lungs where it gets fresh oxygen and
becomes bright red
• Blood from lungs through pulmonary veins
back to the heart's left side pump
• Pumped out into the body
3 Kinds of Circulation:
• Pulmonary circulation
• Coronary circulation
• Systemic circulation
Pulmonary Circulation
Movement of blood from the heart, to the
lungs, and back to the heart again
Coronary Circulation
Movement of blood through the tissues of
the heart
Systemic Circulation
Supplies nourishment to all of the tissue
located throughout the body , except for
the heart and lungs
Blood Vessels
Hollow tubes that circulate your blood
Three Kinds of Blood Vessels
• Arteries
• Veins
• Capillaries
Arteries
•
•
•
•
•
•
Carry blood AWAY from the heart
Heart pumps blood
Main artery called the aorta
Aorta divides and branches
Many smaller arteries
Each region of your body has system of
arteries supplying it with fresh, oxygen-rich
blood.
Arteries
• Tough on the outside
• Smooth on the inside
• Muscular wall helps the heart pump blood
Have strong, muscular walls
The inner layer is very smooth so that the blood
can flow easily
Arteries cause your pulse.
Blood Flow in Arteries
• Blood pressure due to the pumping of the
heart accounts for the flow of blood in the
arteries.
• Systolic pressure is high when the heart
expels the blood.
• Diastolic pressure occurs when the heart
ventricles are relaxing.
• Both pressures decrease with distance
from the left ventricle because blood enters
more and more arterioles and arteries.
Capillaries
• Very thin
• Only one cell thick
• Connect arteries & veins
Unlike the arteries
and veins,
capillaries are very
thin and fragile.
The capillaries are
actually only one
epithelial cell thick.
They are so thin that
blood cells can only
pass through them
in single file.
Capillaries
• Food and oxygen released to the body
cells
• Carbon dioxide and other waste products
returned to the bloodstream
Blood Flow in Capillaries
• Blood moves slowly in capillaries because
there are more capillaries than arterioles.
• This allows time for substances to be
exchanged between the blood and tissues.
Valves are located inside the veins. The valves
only allow blood to move in one direction.
Veins
• Carry blood to the heart
• Receive blood from the capillaries
• Transport waste-rich/ oxygen-poor blood
back to the lungs and heart
• Valves are located inside the veins
• Allow blood to move in one direction
The Veins
• Venules drain blood from capillaries, then
join to form veins that take blood to the
heart.
• Veins have much less smooth muscle and
connective tissue than arteries.
• Veins often have valves that prevent the
backward flow of blood when closed.
• Veins carry about 70% of the body’s blood
and act as a reservoir during hemorrhage.
The Venous System
• Blood flows from capillaries into venules,
then on to veins
• Veins are large-diameter vessels with some
smooth muscle in wall
• Valves in some veins prevent blood from
flowing backward
Blood Flow in Veins
•
1)
2)
3)
Venous blood flow is dependent upon:
skeletal muscle contraction,
presence of valves in veins, and
respiratory movements.
Blood
• Pumped by your heart.
• Travels through thousands of miles of
blood vessels
• Carries nutrients, water, oxygen and waste
products to and from your body cells.
• Made up of liquids, solids and small
amounts of oxygen and carbon dioxide.
Blood
• Plasma is the liquid part of the blood
• About half of your blood is made of plasma
• The plasma carries the blood cells
throughout the body
• Plasma is made in the liver.
Passage of Blood Through the
Heart
• Blood follows this sequence through the
heart: superior and inferior vena cava → right
atrium → tricuspid valve → right ventricle →
pulmonary semilunar valve → pulmonary
trunk and arteries to the lungs → pulmonary
veins leaving the lungs → left atrium →
bicuspid valve → left ventricle → aortic
semilunar valve → aorta → to the body.
Blood Facts
The average adult has about FIVE liters of blood inside of
their body, which makes up 7-8% of their body weight.
Blood is living tissue that carries oxygen and nutrients to
all parts of the body, and carries carbon dioxide and other
waste products back to the lungs, kidneys and liver for
disposal. It also fights against infection and helps heal
wounds, so we can stay healthy.
There are about one billion red blood cells in two to three
drops of blood. For every 600 red blood cells, there are
about 40 platelets and one white cell.
• If you took all of the blood vessels
out of an average adult, and laid
them out in one line, the line would
be over 100,000 miles long!
4
components
of blood
plasma
red
blood
cells
white
blood
cells
platelets
BLOOD CELL TYPES
• Red Blood Cells:
– most numerous
– smaller than white blood cells, larger than
platelets
– no nucleus when mature
– produced in the red marrow of long bones
– destroyed in the liver and spleen
– contain the iron protein compound
HEMOGLOBIN whose chief function is to
combine with oxygen and carry it to the cells
Red Blood Cells- living
• 5 million in 1 drop of blood (most common)
• Shape = donut
Draw here:
• Made in bone marrow
• Live approximately 120-125 days
Hemoglobin = oxygen containing pigment
Binds to oxygen and carries it to the cells
Gives red blood cells its red color
White blood cells- living
• AKA- Lymphocytes or Leukocytes
• White blood cells are larger than red blood
cells, but there are less of them.
• 8000 in one drop of blood
Function of White Blood Cells
 surround and digest bacteria
Attack bacteria and viruses
**Pus = WBC + dead bacteria
YouTube - White Blood Cell Chases Bacteria
White Blood cells
--largest blood cells--several different
types
--most are formed in the bone
marrow or in the lymph tissue
--most protect the body against
diseases by forming antibodies or
engulfing bacteria
Main White Blood Cell Types
1. Phagocytes-- engulf bacteria and
viruses by phagocytosis
--able to leave the bloodstream
and move between the cells of
the body by squeezing through
the capillary walls
2. Lymphocytes--produce antibodies
which clump bacterial poisons or
bacteria (antigens) (antigens--foreign
substances in the body)
Platelets
--smallest blood cells (fragments)
--150,000 to 300,000 per drop of blood
--needed for clotting
Platelets- living
• Bits of cells
• Live for approximately 10 days
Function of Platelets
creates fibrin = enzyme that helps clot
blood (tiny threads seal cuts)
Blood Clots
• Self-healing
materials that plug
leaks in our vessels
• When a blood
vessel is injured
they are activated
– They help trigger the
formation of an
insoluble fibrin clot
that plugs the leak
Clotting:
Involves a series
of enzyme
controlled
reactions resulting
in the formation of
protein fibers that
trap blood cells
and form a clot.
Hemophilia
• Hemophilia is an inherited clotting disorder
due to a deficiency in a clotting factor.
• Bumps and falls cause bleeding in the
joints; cartilage degeneration and
resorption of bone can follow.
• The most frequent cause of death is
bleeding into the brain with accompanying
neurological damage.
Locate the pericardium (bag
around the heart).
pericardium
Locate the coronary artery.
coronary
artery
Find the aorta. What does it
measure across in centimeters?
Measure the thickness of the aorta
wall in centimeters.
The septum is the wall of muscle that
separates the two ventricles. Measure
the thickness of the septum.
Locate the two valves with "strings"
attached.
Locate the pulmonary artery.
What do you see inside the artery?
Draw a heart,
label its
chambers and
major features,
and write brief
captions
describing the
function of each
chamber.
The ABO System
• Discovered in 1901 by Dr. Karl
Landsteiner
• 4 Main Phenotypes (A, B, AB,
O)
• ABO gene located on long arm
of chromosome 9
ABO & Rh(D)
Inheritance of ABO Groups
Allele from
the mother
Allele from
the father
Genotype of
offspring
Blood types of
offspring
A
A
AA
A
A
B
AB
AB
A
O
AO
A
B
A
AB
AB
B
B
BB
B
B
O
BO
B
O
O
OO
O
ABO & Rh(D)
Genetics of Blood Types
• Your blood type is established before you are
BORN, by specific GENES inherited from
your parents.
• These two genes - one gene from your
MOTHER and one from your FATHER determine your blood type by causing proteins
called AGGLUTINOGENS to exist on the
surface of all of your red blood cells.
What are blood types?
Blood Types
There are 3 alleles or genes for blood
type: A, B, & O. Since we have 2 genes,
there are 6 possible combinations.
AA or AO = Type A
BB or BO = Type B
OO = Type O
AB = Type AB
http://learn.genetics.utah.edu/units/basics/blood/types.cfm
How common is your blood type?
Rh Factors
• Scientists sometimes study Rhesus monkeys
to learn more about the human anatomy
because there are certain similarities between
the two species. While studying Rhesus
monkeys, a certain blood protein was
discovered. This protein is also present in the
blood of some people. Other people, however,
do not have the protein.
• The presence of the protein, or lack of it, is
referred to as the Rh (for Rhesus) factor.
• If your blood does contain the protein, your
blood is said to be Rh positive (Rh+). If your
blood does not contain the protein, your blood
is said to be Rh negative (Rh-).
A+ AB+ BAB+ ABO+ O-
Blood Transfusions
A blood transfusion is a procedure in which blood is given to a patient through an
intravenous (IV) line in one of the blood vessels. Blood transfusions are done to replace
blood lost during surgery or a serious injury. A transfusion also may be done if a person’s
body can't make blood properly because of an illness.
Who can give you blood?
Universal Donor
People with TYPE O blood are called
Universal Donors, because they can give
blood to any blood type.
People with TYPE AB blood are called
Universal Recipients, because they can
receive any blood type.
Rh +  Can receive + or Rh -  Can only receive Universal Recipient