Download Circulatory System

Notes: The Circulatory System
The circulatory system is responsible for
transporting materials through the entire body
Functions of the Circulatory System
• The circulatory system functions in the
– Delivery of oxygen
– Delivery of nutrient molecules
– Delivery of hormones
– Removal of carbon dioxide, ammonia
and other metabolic wastes
Parts of the Circulatory System
• 3 parts of the Circulatory
system:
– Heart
– Blood
– vessels
Fun Facts
• The Heart is an amazing organ. It's job
is to pump your blood and keep the
blood moving throughout your body.
• Your heart beats about 100,000 times
in one day and about 35 million times
in a year. During an average lifetime,
the human heart will beat more than
2.5 billion times
Notes: BLOOD
Characteristics
• Metallic (even in taste)
• Slightly alkaline (pH 7.4)
• Approximately 5 Liters
Fun Fact
• Your body has about 5.6 liters (6 quarts)
of blood. This 5.6 liters of blood
circulates through the body three times
every minute.
Functions
– Medium of transport for oxygen, nutrients,
hormones, and waste
– Maintain – body temp, pH, and fluid volume
– Prevent – blood loss, infections
Make up of Blood
Components of blood
• Plasma – 55% of blood, fluid matrix,
90% water, non-living
• Formed elements – 45% of blood, solid,
living, produced by bone marrow
– Erythrocytes (RBC)
– Leukocytes (WBC)
– Platelets
Red Blood Cells
• Red Blood Cells are responsible for carrying
oxygen and carbon dioxide.
• Red Blood Cells pick up oxygen in the lungs
and transport it to all the body cells.
Life Span of an RBC
• Life-span of an erythrocyte is only 120
days, after which they are destroyed in
liver and spleen.
White Blood Cells (leukocytes )
• are larger than erythrocytes,
They function in the cellular immune
response.
• White blood cells (leukocytes) are less
than 1% of the blood's volume.
Platelets
• Platelets are blood cells that help stop
bleeding.
– When we cut ourselves we have broken a
blood vessel and the blood leaks out.
– To plug up the holes, the platelets start to
stick to the opening of the damaged blood
vessels.
– As the platelets stick to the openings they
attract more platelets, fibers and other blood
cells to help form a plug to seal the broken
blood vessel.
Blood Types
• A, B, AB, O (others are rare)
– AB – universal recipient, least common
– O – universal donor, most common
Rh
• Named for Rhesus Monkey
• Rh+ - 85%, have antigens
• Rh- - 15%, don’t have antigens
• -woman and +man have will have
problems with pregnancy
Heart
• Characteristics
– Fist sized
– Less than 1 pound
– Behind and left of sternum
– Surrounded by pericardium – sac filled with
thin layer of fluid
Heart - Layers
• Epicardium – outermost, covered by fat
• Myocardium – middle, actual cardiac
muscle, contracts to pump blood
• Endocardium – inner most, contact with
blood, connective tissue replaceable
Chambers of the Heart
• Atria – 2, superior, receive blood
• Ventricles – 2, inferior, send out blood
– Atriums contract while ventricles relax.
– Ventricles contract while Atriums relax
Make up of the heart
• Blood is brought back to the heart by
veins & carried away from the heart by
arteries
Arteries
Structure of a vein
Arteries
Capillaries
• Capillaries are tiny
blood vessels. Only
1 RBC fits though at
a time
• Capillaries are only
1 cell thick
• Capillaries connect
arteries to veins.
Heart
• Pulse rate – average number of heart
beats in a minutes
– 72 beats/min. is average for an adult
• Circulation – path blood takes when
moving through the body
Circulation - pathways
• Pulmonary – takes blood to and from
lungs for gas exchange
• Systemic – takes oxygenated blood to
rest of the body and brings
deoxygenated blood back to the heart
Cardiac Cycle
• All events associated with flow of blood
in heart in one complete heart beat
– Systole – contraction phase
– Diastole – relaxation phase
Angina
• Pain associated with a decrease in
amount of blood going to myocardium
Myocardial Infarction
• Heart attack
• Prolonged blockage or great decrease in
blood getting to the heart
Heart Murmur
• Valves not closing properly leading to a
leak
Arrhythmia/ Fibrillation
• Irregular hear rhythms
Varicose Veins
Valve does not work properly and blood leaks back
into the vein filling it up and causing it to swell.
Healthy Heart
• It is your job to keep your heart healthy &
there are three main things you need to do:
– Exercise on a regular basis. (walk, jog, run,
bike, skate, jump, swim).
– Eat Healthy. Stay away from high fat foods
and have your cholesterol checked regularly
– Don't Smoke! Don't Smoke! Don't Smoke!
CW: Heart Anatomy & Flow of Blood
AMAZING FACTS
• One drop of blood contains a half a drop of
plasma, 5 MILLION Red Blood Cells, 10
Thousand White Blood Cells and 250
Thousand Platelets.
• You have thousands of miles of blood vessels
in your body. Anywhere between 75,000 100,000 miles. The earths diameter is 25,000
miles. So your blood vessels could circle
around the equator 3 to 4 times!
• Keep your heart healthy...it's going to have to
beat about 3 BILLION times during your
lifetime!