Transcript The Circulatory System

The Circulatory System
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About the system
Blood
Heart
Vessels
About the circulatory system
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Heart
Blood vessels – arteries and veins
Blood
Functions of the circulatory
system
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Transportation of gases, nutrients, ions and
waste
Transports oxygen, carbon dioxide
Transports glucose, fats, amino acids
Transports hormones
Regulation of body temperature
Defense against disease – clotting and
immunity
http://greenfield.fortunecity.com/rattler/46/blood.htm
Use this information to complete the table
in your worksheet
A few nights working in a trauma center would tend to
convince one that the body is just a huge bag of blood. In
fact, an "average" 70 litre human body contains only about 5
litres of blood, or 7% by volume. In the normal state, blood
has no business anywhere except in the confines of the heart
and blood vessels and in the sinusoids of the marrow, liver,
and spleen. Of the average 5 L of blood, only 2.25 L, or 45%,
consists of cells. The rest is plasma, which itself consists of
90% water (by weight) and 10% solids (mostly proteins, the
greatest proportion of which is albumin). Of the 2.25 L of
cells, only 0.037 L (1.6%) are leukocytes. The entire
circulating leukocyte population, if purified, would fit in a
bartender's jigger. The total circulating platelet volume is
even less -- about 0.0065 L -- or a little over one teaspoonful.
Composition of Blood
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Plasma 55%
Blood Cells 45%
http://www.medicine.mcgill.ca/physio/vlabonline/bloodlab/hemat.htm
Blood plasma – 55%
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55% of the blood
slightly alkaline fluid
typical yellowish color
90 % water, 10% dry matter
organic substances – glucose, lipids,
proteins
dissolved minerals
Blood cells – 45%
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Red Blood Cells 99%
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White Blood Cells <1%
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Platelets
http://www.bayinsider.com/shared/health/adam/ency/imagepage/9123.000571.html
Blood cells – 45%
Red Blood Cells = Erythrocytes
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Most numerous blood
cells
No nucleus
Biconcave shape
Rich in haemoglobin … a protein
which can bind oxygen
Last 120 days then recycled
White blood cells = Leukocytes
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Less than 1% of blood cells
Vital for defense against disease
Many different types
Neutrophils
Basophils
Eosinophils
Monocytes
Lymphocytes
Cells in the blood
Erythrocytes
Lymphocytes
Monocyte
Platelets
http://www.mybloodyourblood.org/sFRwhitecells.htm
How blood cells are made
Platelets
The main function of platelets is to stop the loss of
blood from wounds. To this purpose, they
aggregate and release factors which promote the
blood coagulation.
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reduce the diameter of damaged vessels
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slow down blood flow in that area
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trap cells to form the clot.
Even if platelets appears roundish in shape, they are
not real cells.
The Heart
http://www.jdaross.cwc.net/heart.htm
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Size of a clenched fist
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Approximately 300 g
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5-35 litres per minute
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70 beats/minute
Blood vessels
Heart
Arteries
Veins
Arterioles
Venules
The whole system
Sickle cell anaemia
http://k14education.uams.edu/SickleCell/about.html
References
http://www.neosoft.com/~uthman/blood_cells.html
http://www.funsci.com/fun3_en/blood/blood.htm#0
http://www.bayinsider.com/shared/health/adam/ency/i
magepage/9123.000571.html