Download Circulatory System 2013-2014

Circulatory System
in Animals
2008-2009
Feeding Energy Needs
 Why do we need a
circulatory system?

supplies in
 fuel (sugars)
 digestive system
 oxygen
 respiratory system

waste out
 CO2
 respiratory system

need to pick up & deliver
the supplies & wastes
around the body
 circulatory system
Circulatory System
 Organ

heart
 Tissues & cells

blood vessels
 arteries
 veins
 capillaries

blood
 red blood cells
 plasma (liquid)
Vertebrate Heart
 4-Chambered heart

atria (atrium)
 thin wall
 collection chamber
left
atrium
 receive blood

ventricles
 thick wall pump
 pump blood out
right
atrium
right
ventricle
left
ventricle
Evolution of circulatory system
Not everyone has a 4-chambered heart
fish
2 chamber
V
amphibian
3 chamber
A
A
A
V
reptiles
3 chamber
A
V
A
V
birds & mammals
4 chamber
A
V
A
V
Lub-dub, lub-dub
 4 valves in the heart


flaps of tissue
prevent backflow of blood
 Heart sounds


closing of valves
“Lub”
SL
AV
AV
 force blood against
closed AV valves

“Dub”
 force of blood against
semilunar valves
 Heart murmur


leaking valve causes hissing sound
blood squirts backward through valve
The Human Heart – Greater Details
The Heart: Internal Structure
ANATOMY OF THE HEART
General Characteristics:
• slightly larger in size than
a clenched fist
• double, self-adjusting
pump
• weight varies from 280 to
340 g in men and from
230 to 280 g in women
• four chambers
• 3 layered wall
Will need
ONE red/pink
pencil and
ONE
blue/purple
pencil)
HEART - EXTERNAL ATTACHMENTS
The heart is located
in the mediastinum.
It is surrounded by a
sac, called the
parietal pericardium
(protects the heart).
This sac is composed
mainly of white
fibrous C.T.
It is attached to the
following structures:
1). Diaphragm
2). the back of the
sternum
3). the vertebral
column
4). the large blood
vessels that extend
out of the heart
3 Layers of
Heart Wall
 Epicardium
 Myocardium
 endocardium
1. visceral pericardium / epicardium =
(a serous membrane that covers the
heart)
•outermost, protective layer of the
heart.
•Between the parietal pericardium (sac
that surrounds the heart) and this
layer, there is a space called the
pericardial cavity. I
•contains a small amount of serous
fluid (helps reduce friction when the
heart moves)
•
2). myocardium = This is
the middle layer of the heart
wall. It is composed of
cardiac muscle.
It produces the muscular
contractions which force the
blood through the heart.
3). endocardium = This is
the innermost layer of the
heart wall.
It is composed of epithelium
and connective tissue.
It protects the heart
chambers and valves.
ANATOMY OF THE HEART
Four Chambers:
The human heart contains four chambers:
The two upper chambers are the left and right auricles /
atria (singular = atrium).
The two lower chambers are the left and right ventricles
The two chambers on the right (atrium and ventricle) are
separated from the two chambers on the left (atrium
and ventricle) by the interventricular septum.
Lets take a look!
Left atrium
Right Atrium
Right ventricle
Left
ventricle
Heart Valves
The movement of
blood through the
heart is aided by
"flaps of tissue"
called valves.
 There are four of
these valves in the
heart
Pulmonary Circuit
RIGHT SIDE
tricuspid valve
Location: Between right atrium and
ventricle, one-way valve
 composed of three flaps of tissue
 three flaps are regulated by
tendinous cords called chordae
tendineae.
 The cords originate from mounds
of tissue called papillary muscle
Blood flow: The tricuspid valve
opens as the blood flows from the
right atrium to the right ventricle.
Then it closes to prevent any
back-flow of blood (when the
ventricle contracts).
RIGHT SIDE
pulmonary (semilunar)
valve
Location: between this ventricle
and pulmonary artery
 composed of three curved flaps
which resemble "half moons"
(hence the name semilunar).
 closes once ventricle contracts
and fills the artery with blood
(prevents back-flow of blood)
[NOTE: The pulmonary artery splits
into the left and right pulmonary
arteries. One of these vessels
goes to each lung.]
Systemic Circuit: LEFT SIDE
bicuspid / mitral valve
Location: between the
left atrium and
ventricle
composed of two flaps
of tissue [which are
regulated by chordae
tendineae] …prevents
back-flow.
The left ventricle
connects with a large
blood vessel called
the aorta.
LEFT SIDE
aortic semilunar valve
Location: between the left
ventricle and aorta.
Its function is similar to that
of the pulmonary
semilunar valve.
NOTE: The walls of the left
ventricle are much thicker
than the right ventricle
because the left ventricle
must force the blood
throughout the body.
 aortic (semilunar)
valve
When the blood circulates through the body,
it must make two trips through the heart:
 1 trip = through the right side and into the
lungs where it is oxygenated
 Called pulmonary circuit
Handout E
Now color in
the pulmonary
circuit (BLUE
OR PURPLE)
1 trip = through the left side where it travels
to parts of the body to provide oxygen etc.
 Called Systemic circuit
There is always some blood traveling both
pathways at the same time.
Now color in the
systemic circuit (RED
OR PINK)
Heart and Electricity!
Regents Biology
Hand out F
Electrical signals
allows atria to empty
completely before
ventricles contract
stimulates ventricles
to contract from
bottom to top, driving
blood into arteries
 heart pumping controlled by electrical impulses
 signal also transmitted to skin = EKG
Handout G
atria empty
into ventricles
Cardiac Cycle
How is this
reflected in
blood pressure
measurements?
chambers begin
to fill
pump (peak pressure)
__________________
fill (minimum pressure)
110
______
80
ventricles
pump
Measurement of blood pressure
hypertension =
(high blood pressure)
if top number > 150
or
if bottom number > 90
Have a heart?
Ask Questions!!
2008-2009
Circulatory System
Blood Vessels
2008-2009
Blood vessels
arteries
veins
artery
venules
arterioles
arterioles
capillaries
venules
veins
Arteries: Built for their job
 Arteries
blood flows away from heart
 thicker walls

 provide strength
for high pressure
pumping of blood

elastic & stretchable
Major arteries
aorta carotid = to head
to brain & left arm
to right arm
to body
pulmonary
artery
pulmonary
artery =
to lungs
coronary arteries
Coronary artery bypass
bypass surgery
Veins: Built for their job
 Veins
Blood flows
toward heart
blood returns back to heartOpen valve
 thinner-walled

 blood travels back to heart
at low speed & pressure
 why low pressure?
 far from heart
 blood flows because muscles
contract when we move
Closed valve
 squeeze blood through veins

valves in large veins
 in larger veins one-way valves
allow blood to flow only toward heart
Major Veins
superior
vena cava =
from
upper body
pulmonary
vein =
from lung
inferior
vena cava = from lower body
pulmonary
vein =
from lung
Structure-function relationship
 Capillaries
very thin walls
 allows diffusion of
materials across
capillary

waste
body cell
CO2
 O2, CO2, H2O,
food, waste
O2
food
Circulation of Blood
Circulation
to lungs
 2 part system

Circulation to lungs
lungs
 blood gets O2 from lungs
 drops off CO2 to lungs
 brings O2-rich blood from
lungs to heart

heart
Circulation to body
 pumps O2-rich blood to body
 picks up nutrients from
digestive system
 collects CO2 & cell wastes
body
Circulation
to body
Vertebrate circulatory system
 2 part system
lungs
artery
to lungs
vein from lungs
to heart
heart
vein from body
to heart
body
artery
to body
Stops along the way…
 Lungs

pick up O2 / clean out CO2
 Small Intestines

pick up nutrients from
digested food
 Large Intestines

pick up water from
digested food
 Liver

clean out worn out
blood cells
More stops along the way…
 Kidneys
filters out cell wastes
(urea)
 extra salts, sugars
& water

 Bone

pick up new red
blood cells
 Spleen

pick up new white
blood cells
Circulatory System & Homeostasis
ATP
 Homeostasis




keeping the internal environment of the
body balanced
need to balance food & O2 in
need to balance energy (ATP) production
need to balance CO2 & waste out
 Exercise

heart beat faster
food
O2
CO2
waste
 need more ATP
 bring in more O2 & food; remove more CO2 & waste out
 Disease

poor lung or heart function = heart beat faster
 need to work harder to bring in O2 & food & remove wastes
Have a heart?
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2008-2009
Circulatory System
Blood
2008-2009
Blood & blood cells
 Blood is a tissue of fluid & cells

plasma
 liquid part of blood
 dissolved salts, sugars, proteins, and more

cells
 red blood cells (RBC)
 transport O2 in hemoglobin
 white blood cells (WBC)
 defense & immunity
 platelets
 blood clotting
Parts of the Blood (see Handout A)
Blood Cell production
ribs, vertebrae,
breastbone & pelvis
 Stem cells
“parent” cells
white blood cells
in bone
marrow
 develop into all
the different
types of blood
red blood
cells

 red blood cells
 white blood cells
cells
white blood
cells
BLOOD CELL FORMATION
hemocytoblast
(stem cell)
myeloid
stem cell
(progenitor cell)
megakaryoblast
megakaryocyte
erythroblast
myeloblast
erythrocytes
myelocyte
lymphoid stem
cell
(progenitor cell)
lymphoblast
monoblast
monocyte
agranular
leukocytes
lymphocytes
T (lymphocyte) cells
neutrophilss
platelets
B (lymphocyte) cells
basophils
eosinophils
granular leukocytes
NK cells
macrophages
plasma
cells
Red blood cells
 Small round cells
produced in bone marrow
 5 liters of blood in body
 5-6 million RBC in drop of human blood
 last 3-4 months (120 days)

 filtered out by liver
 ~3 million RBC destroyed each second
Red blood Cells (Erythrocytes)
 develops from an
Facts
erythroblast.
 small, biconcave,


disk-shaped cell
By the time it has
fully matured it has
lost its nucleus and
most of its
organelles
Is able to alter
shapes in order to
pass through the
smallest blood
vessels (capillaries)
The function of the RBC
 To carry O2 to the
tissues and to carry
CO2 out of the
tissues.
 This is accomplished
by a protein found
inside the RBC called
hemoglobin.
 There are about 280
million hemoglobin
molecules per RBC.
A hemoglobin molecule
is composed of two parts
 The heme
portion has
iron (Fe) as
part of its
structure.
 The globin part
of the molecule
is composed of
four
polypeptides
(proteins).
Heme Portion
 The iron is able to


bond with oxygen.
Each molecule is able
to pick up four O2 (8
atoms of O) as the
RBC travels through
the lungs.
This gives each RBC
the potential to carry
about 1 billion oxygen
molecules.
 When the oxygen is
present the
molecule is called
oxyhemoglobin
(bright red).
dark red (venous)
or
bright red (arterial)
 As the oxygen is
released to the
tissues, the
molecule is called
deoxyhemoglobin.
(darker in color;
may appear bluish
when viewed
through the vessel
walls).
Globin portion
The amino (NH2) parts of the amino
acids (that form the polypeptides )are
able to bond with CO2.
Allows hemoglobin to pick up some of
the CO2 produced (about 20%) as a
waste and transport it to the lungs for
removal.
See Handout B : White Blood Cells
B
BNeutrophils:
2 to
first
respond
to
infection
B3 Basophils
B5
Macrophages
B6
emergency repair of circulatory system
Blood clotting
chemical
emergency
signals
platelets
seal the hole
protein fibers
build the clot
Cardiovascular disease
 Atherosclerosis & Arteriosclerosis

deposits inside arteries (plaques)
 develop in inner wall of the arteries,
narrowing their channel


increase blood pressure
increase risk of heart attack, stroke, kidney damage
normal artery
hardening of arteries
Cardiovascular health
 Risk Factors
genetics
 diet

 high animal fat

exercise & lifestyle
 smoking
 lack of exercise
bypass surgery
Heart Disease
Heart disease death rates 1996-2002
Adults ages 35 and older
Women & Heart Disease
Death rates for heart disease per 100,000 women, 2002
Risk factors
 Smoking
 Lack of exercise
 High fat diet
 Overweight
 Heart disease is 3rd leading cause of death
among women aged 25–44 years & 2nd
leading cause of death among women aged
45–64 years.
Have a heart?
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2008-2009