Download Introduction to the Heart and Circulatory System

Introduction to the Heart and
Circulatory System
Have a Heart!
Write down everything that
is underelined on a separate
sheet of paper!
Secretariat
How Big is the Heart?
• A human heart is about 10.5 ounces
• The average Thoroughbred horse heart weighs 9
pounds
– Secretariat: Could finish the quarter mile race
at speeds of 49 MPH
(Man O War only maxed out at about 40 MPH)
– Upon autopsy found that his heart weighed
about 22 pounds!
• Found to be a genetic factor carried on the X
chromosome of the mare
• Not a mutation because the heart was in
correct proportion
Functions of the Circulatory System
• Transports oxygen, nutrients, and other
essential compounds to all cells.
• Transports CO2 and other wastes away
from cells for elimination from the body.
• Helps maintain Homeostasis of body cells.
Three Main Parts of the Circulatory
System
• Heart
• Blood Vessels
• Blood
BloodThe liquid substance of the circulatory system;
made of:
• Plasma
• Red blood cells
• White blood cells
• Platelets
• Draw a picture of each using the following
slides!
Plasma
• The “liquid” of blood material.
• Made up of 90% water
• Contains dissolved substances including:
glucose, vitamins, minerals, and amino acids.
Red Blood Cells
• Made in red marrow of bones
• Contains a protein called hemoglobin which
carries oxygen in the blood.
• Numerous red blood cells contained in the
body, these cells cannot repair themselves
and die after a period of
time.
White Blood Cells
• Help fight disease.
• Animals which are diseased will increase
white blood cell numbers.
• Pus which forms around wounds is white
blood cells.
• Sometimes called soldiers
for their roll in fighting disease.
Platelets
• Not complete cells but are essential for blood
to clot
• Important to stop the blood loss created by
wounds.
Blood Vessels
• Hollow tubes that circulate your blood
Heart
• The Main Pump
• The heart is divided into 4 chambers that
are connected by valves
– Valves are flap-like structures that allow blood
to only flow in one direction
– The audible sounds heard in the heart (Lubdub) are actually the valves closing
• When a valve is not working properly the
sound will be different creating a “Murmer”
The Chambers of the Heart
• There are 4 chambers divided into “upper”
and “lower” chambers
• There are two hemispheres of the heart;
the right and left side, divided by the
septum
Atria
– Upper Chambers of the Heart
– Right Atrium:
• Receives blood from the vena
cava as it returns to the heart
– Left Atrium:
• Receives blood returning to the
heart from the pulmonary veins
Ventricles
• The lower chambers of the heart
• Right Ventricle:
• Receives blood from the right atrium
and pumps it to the pulmonary artery
• Left Ventricle:
• Receives blood from the left atrium
and pumps it to the aorta
The Heart
The Heart
Diagram
• Using your heart
diagram, fill in
the missing
answers
Blood Flow through the Heart
• De-oxygenated (no oxygen)
blood flows from the vena
cava into the right atrium
• The right atrium empties
its contents into the right
ventricle
• COLOR your heart diagram
Blue (code blue – deoxygenated) & Red
(oxygenated) according to
picture
Blood Flow Continued
• De-oxygenated
blood is pumped
into the pulmonary
artery
• The pulmonary
artery carries
blood to the lungs
where it picks up
oxygen
• The blood is
returned to the
left atrium by the
Flow of blood through the heart!
Un-oxygenated blood enters through the
vena cava
right atrium
through the
tricuspid valve into the right ventricle
through the pulmonary artery (away)
to the
lungs to get oxygen back through the
pulmonary vein
into the left atrium
through the mitral valve into the left
ventricle
out the aorta
Pericardium
• Fluid filled sac
around the heart
• Function
– Keeps the heart
in the chest
cavity
– Prevents the
heart from over
expanding
– Limits heart
motion
• Pericardial Membranes
– Fibrous
• Outer fibrous
sac
– Parietal
• Lies between
visceral and
fibrous
– Visceral
• Outer layer of
the wall of the
heart
Heart Wall
• Epicardium
– Outer layer of the wall of the heart
– Provides protection
• Myocardium
– Muscular middle layer of the heart
– Stimulates heart contractions to pump blood
from the ventricles and relaxes to allow the
atria to receive blood
• Endocardium
– Inner layer of the heart
– Participates in the contraction of the heart
Heart Health
• Oh My! Maybe I
should lay off of the
corn!
• Because swine and
humans are so
compatible, heart
valves are
commonly used
from pigs to repair
those in humans!
Are you Ready Doctor?
• http://www.pbs.org/wgbh/nova/eheart/transpl
antwave.html
• Demo of a Heart Transplant