Transcript SNC2D Circulatory System

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Moves oxygen from the lungs to all the body cells
Moves carbon dioxide from the body cells to the
lungs
Moves nutrients from the small intestine to the body
cells
Moves waste materials from the body cells to the
kidneys and skin
Regulates the body temperature and transports
disease-fighting white blood cells to sites of viruses
or bacteria
Heart – the pump
Blood – the fluid in
which materials
are transported
Blood Vessels –
the tubes to
carry the blood
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Blood is a type of connective tissue that
circulates through your body, it consists of
4 parts:
◦ Red Blood Cells (RBC) – (oxygencarrying cells)
- 45% of the blood’s volume
- contains a protein called hemoglobin
(carries the oxygen)
- makes the cells appear red
Did you know…
- It takes about 20
seconds for a RBC
to circulate the
entire body
◦ White Blood Cells (WBC) –
(infection-fighting cells)
-less than 1% of the volume of blood
-the only blood cell with a nucleus
◦ Platelets – (blood clotting cells)
-less than 1% of the blood
◦ Plasma – (protein-rich liquid)
-about 55% of blood’s volume
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There are 3 types of blood vessels:
Arteries carry oxygenated blood away. Arteries are
thicker than the other vessels
Veins carry deoxygenated blood toward the heart. Blood
is at lower pressure – walls are not as thick
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Capillaries is where the gas exchange occurs. They are
very thin & narrow. O2 diffuses from the blood to the
surrounding tissues and CO2 and other wastes pass from
the body to the blood to be carried out for disposal.
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composed of:
cardiac muscle tissue, nerve tissue,
connective tissue and epithelial
tissue
cardiac muscle tissue undergoes
contractions & conducts electrical
impulses
frequency of heart beat (heart
rate) depends on your physical
activity level and other factors
(stress, general health, etc).
 Regulated by nerve tissue.
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Did you know…
◦ Your circulatory system
is about 95,000 km long
◦ Your heart beats more
than 2.5 billion times in
the average lifetime
◦ the human heart creates
enough pressure when it
pumps to squirt blood
30 feet.
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muscles & nerves are covered by
a smooth layer of epithelial tissue
 reduces friction & protects the
heart from damage when the
lungs expand and contract.
inner surface is lined with
epithelial tissue to allow the
blood to flow freely.
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Did you know…
◦ Your circulatory system
is about 95,000 km long
◦ Your heart beats more
than 2.5 billion times in
the average lifetime
◦ the human heart creates
enough pressure when it
pumps to squirt blood
30 feet.
Path of Blood in the Heart
•blood is collected in the atria (plural of atrium) via veins
•atria walls contract, blood is pumped from the atria to the ventricles
via opened atrio-ventricular (AV) valves
•semi-lunar valves are closed to prevent blood from flowing to
arteries while the ventricle fills up with blood
•ventricle walls contract, causing rise in blood pressure
Path of Blood in the Heart
•high blood pressure cause AV valves to close to prevent back flow of
blood to atria
•high blood pressure also cause semi-lunar valves to open to allow
blood to be pumped from ventricles to arteries
•as blood leaves ventricles, pressure inside the ventricles drop and
ventricles stop contracting
•the semi-lunar valves close to prevent back flow of blood from
arteries to ventricles
Coronary Artery Disease (CAD)
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Coronary arteries provide blood to the heart muscle tissue itself
Can be blocked with plaque – a deposit of fat, cholesterol,
calcium, etc.
Plaque buildup can be caused by inherited genetic information,
poor lifestyle choices, i.e. high-fat diet, smoking, lack of exercise.
Symptoms – tiredness, dizziness, pain or a burning in chest &
arms
can be diagnosed with the aid of an angiogram (X-ray), a
fluorescent dye is injected into the bloodstream
Heart Attack
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Coronary arteries become blocked by plaque or a blood clot
Heart muscle cells no longer receive the O2 or nutrients
Heart stops pumping, heart tissue dies
Symptoms: chest pain or pressure, shortness of breath, nausea,
anxiety, upper body pain, abdominal or stomach pain, sweating,
dizziness, unusual fatigue
Requires immediate medical attention
Can be diagnosed with a blood test (looks for certain proteins that
are only present when cardiac muscle dies) and an
electrocardiogram, ECG (measures the electrical signals created by
the heart as it beats)
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Read pg. 100 - 103
“Circulatory System Package”