Post on 13-Dec-2015
Pathway of Circulation14
9
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16
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7
And so on…It takes about 1 min. for blood to make 1 complete cycle
Pulmonary Circuit
Systemic Circuit
Lung
Pulmonaryvein
Aorta
Left atrium
Leftventricle
Pulmonaryartery
Rightatrium
Rightventricle
Venacava
oxygen-poor blood
oxygen-rich blood
CardiovascularCircuits
Pulmonary Circulation Takes place on the right side of the heart. Pumps
blood low in oxygento the lungs to pick up oxygen and return to heart
Systemic Circulation Takes place on left side of heart Oxygenated blood is pumped to
the body cells thruthe aortaand otherarteries
Blood lowin oxygenreturns to the heart
Coronary Circulation
Although blood fills the chambersof the heart, the muscle tissue of the heart is so thick that it requires coronary blood vessels to deliver blood deepinto the myocardium.
The coronary circulation consists of the blood vessels that supply blood to, and remove blood from the heart muscle itself.
Coronary Circulation
The vessels that supply blood high in oxygen to the myocardium are known as coronary arteries.
Blood Vessels Form a closed circuit
of tubes that carry blood throughout the body
Laid end to end, the blood vessels in an average human body will stretch approximately 62,000 miles……2.5 times around the earth
Blood Vessels Have
characteristic features
Are distinguished by size, tissue layers and direction of blood flow
Blood Vessels Arteries
• Receive blood from ventricles
• Take blood away from the heart
• Usually carry oxygenated blood
• Thickest vessel walls• Withstand greater blood pressure• Are very elastic• Connect to capillaries• Aorta is the largest artery
Blood Vessels Veins
• Transport blood away from capillaries• Carry blood
toward heart• Take blood to atria• Have valves• Thinner vessel
walls with lesssmooth muscles
than arteries• Can stretch a great deal• Have larger diameters• Usually carry de-oxygenated blood• Vena cava is the largest vein
Blood Vessels The contraction of muscles
compressing veins helps push blood up through the leg veins back to the heart. The valves allow the blood to flow towards the heart only.
Calf musclerelaxed
Calf musclecontracts
Musclesqueezes veins
Veins constrict;blood moves;valves open
Veins dialated;blood still;valves closed
Valves OPEN
Valves CLOSED
Blood Vessels Capillaries
• Smallest of blood vessels• Only one cell thick (epithelial cell)• Connect arteries to veins• Bring oxygen
and nutrients to cells
• Removes CO2, urea, and other wastes from cells
• Where blood is under low pressure and moving slowly
Blood Vessels A network of capillaries runs
close to the cells in every part of the body. The capillaries have very thin walls which allows nutrients to diffuse through into the tissues and waste products to filter back into the capillaries.
Arteriole Venule
Tissue cells VeinArtery capillaries
Capillaries
Blood PressureBlood pressure refers to the force
exerted by circulating blood on the walls of blood vessels
The pressure of the circulating blood decreases as blood moves through arteries, arterioles, capillaries, venules, and veins
Blood Pressure Blood pressure is most commonly
measured via a sphygmomanometer(blood pressure cuff)
It uses the height of a column of mercury to reflect the circulating pressure
Average blood pressure for an adult is 120/80
Blood Pressure
Systolic pressure is defined as the maximum pressure in the arteries exerted during ventricular contraction (which occurs near the beginning of the cardiac cycle)
Diastolic pressure is the minimum pressure exerted when ventricles relax and fill (at the resting phase or end of the cardiac cycle)
Blood pressure readings = S/D
Blood Pressure Pressure waves move through
the blood vessels A person's pulse is the throbbing
of their arteries as an effect of the pressure waves (heart beat)
Pulse is used to denote the frequency of the heart beat
It can be felt at neck, wrist, and other places
Pulse is usually measured in beats per minute.
In most people, the pulse is an accurate measure of heart rate..
Blood Pressure
Vasoconstriction is narrowing of a blood vessel. When a blood vessel constricts, the flow of
blood is restricted or slowed. Blood pressure will increase Vasodilatation is where blood vessels in the
body become wider following relaxation of smooth muscle in vessel wall. This will reduce blood pressure - since there is more room for the blood.
and
Blood
The life stream of the body, affecting every cell and system we have.
The blood is an accumulation of many different elements, each working in a specific way to keep us alive.
Blood
A circulating connective tissue consisting of several types of cells suspended in a fluid medium known as plasma.
Blood
Functions of blood:• Supply oxygen to tissues • Supply nutrients such as glucose, amino acids
and fatty acids to tissues
• Removal of wastes such as CO2
, urea and lactic acid from tissues
• Immunological functions, including circulation of white cells, and detection of foreign material by antibodies
Blood
Functions of blood continued:• Messenger functions, including transport of
hormones and signaling of tissue• Coagulation,
part of body's self-repair mechanism
• Regulation ofcore body temperature
• Regulation of body pH and ion concentrations
Blood What percent of your body is blood? How much blood do we contain?
• On average 4-6 liters• We contain about a pint of
blood for every 15 pounds of body weight
Composition of Blood:• What percent of your blood is
cellular? • What percent of your blood is
plasma?
8%
45%
55%
Blood What is plasma?
• A clear, straw colored fluid
• What percent of plasma is water?
• What’s in plasma? Dissolved gasses Vitamins Minerals Salts Nutrients
Enzymes Hormones Waste products Plasma proteins
90%Buffy coat leukocytesand platelets(<1% of whole blood)
Erythrocytes(45% of whole blood)
Plasma(55% of whole blood)
Formedelements
Layering of blood components in a centrifuged blood sample
Blood
The cellular components are:• red blood cells
(erythrocytes)• white blood cells
(leukocytes) • platelets
(thrombocytes) Blood cells are
formed in bonemarrow
Blood
Red Blood Cell CharacteristicsRed Blood Cell Characteristics• (RBC)- Erythrocyte(RBC)- Erythrocyte• Biconcave disksBiconcave disks• No nucleusNo nucleus• Contain the iron based pigment Contain the iron based pigment
hemoglobinhemoglobinwhich binds with oxygen to transport itwhich binds with oxygen to transport it
• Life span about 120 daysLife span about 120 days• 5 billion/1mL of blood = most numerous 5 billion/1mL of blood = most numerous • Are very smallAre very small
Blood
To the right is an artist's drawing showing the biconcave shape of the red blood cell.
To the right is a Wright's stained peripheral blood smear under 1000 X magnification.
The average size of a red blood cell is 7.2 micrometers in diameter.
Blood
How RBC’s transport oxygen....Hemoglobin .…the iron containing pigment
Hemoglobin makes red blood cells red
Blood
White Blood Cell Characteristics• (WBC)- Leukocyte• No definite shape• Have nucleus• Protect body against infection• Life span varies (3 days-a few
months)• 7,000/1mL of blood• Numbers increase if
infection is present• Larger than RBC’s
Blood
Types of white blood cells:• Monocytes are the
largest• Neutrophils are
the most numerous
• Lymphocytes are produced by the lymph tissue
• Basophils releasehistamines