Study Notes
Circulation (Heart)
Blood Vessals
|
Blood Vessel
|
Structure
|
Thickness of Wall
|
Valves
|
Direction of Blood Flow
|
|
Arteries
|
3 layers,
endothermus, elastic fibers, smooth muscle.
|
2.5 mm wide
|
No
|
Away from heart.
|
|
Arterioles
|
Elastic tissue,
smooth muscle fibre.
|
Under 0.5mm to
naked eye.
|
No
|
Away from heart.
|
|
Capillaries
|
One cell thick
walls, one endotherum membrane.
|
8-10mm wide
|
No
|
To heart and
away.
|
|
Venules
|
Same 3 layers as
arteries, less smooth muscle.
|
Thin walls
|
Yes
|
To heart.
|
|
Veins
|
Same 3 layers as
arteries, less smooth muscle.
|
Thin walls
|
Yes
|
To heart.
|
Identify and give functions for
each of the following :
Subclabian arteries and veins :
blood vessels located in the chest region of the body, which serve to transport
blood to the head and arms to and from the heart
Jugular veins : branch off the
subclacian vein which brings deoxygenated blood from head and arms back to
heart
Carotid veins : blood vessels
along neck
Mesenteric Veins : arteries
which branch off the aorta it serves blood to the digestive tract
Anterior and posterior vena
cava: superior and inferior venacava which bring blood to the right atrium
Pulmonary veins and arteries: veins
and arteries which bring blood to the lungs and exchange substances at the
lungs capillary beds.
Hepatic portal vein: veins that
connect small intestine with the liver
Renal arteries and veins : blood
vessels which bring and take away blood at the kidneys
Iliac arteries and veins : blood
vessels which transport blood between the legs and heart
Coronary arteries and veins :
the external coronary arteries are the first branch off the aorta, They
eventually become arterioles caloillaries and veins.
Aorta : major systemic artery
that receives blood from left ventricle
Distinguish
between pulmonary and systemic circulation:
Pulmonary
circulation is the circulation of blood between the heart and the lungs.
Systemic circulation is the circulation of blood between the heart and the rest
of the body parts that require oxygen to function.
Identify
and describe differenced in structure and circulation between fetal and adult
systems :
The
featus has several structures in its circulatory system that the adult does
not.
1.)
Foramen ovale-an opening between the two atria. This opening is covered by a
flap of tissue that acts as a valve, It travels between the atria so less blood
enters lungs.
2.)
Arterial Duct- is a connection between the pulmonary artery and aorta. It
functions as to keep deoxygenated blood from being circulated back into fetus
developing brain.
3)
Umbilical artery-carries deoxygenated blood and wastes to the placenta.
4)
Umbilical Vein- carries oxygenated blood and nutrients to the baby from the
placenta
5)
Venous duct-is connected between the umbilical vein and inferior vena cava.
Demonstrate
a knowledge of the path of blood from the aorta through the body and back to
the left ventricle:
List
major components of plasma :
-water
(maintains blood volume and transports molecules)
-plasma
protein
-Albumin
(transports bilirubin, maintains blood volume and pressure)
-Fibrinogen
(clots)
-Immunoglobulins
(transport, fight infection)
Describe
the shape, function and origin of the red blood cells, white blood cells and
platelets:
-Red
blood cells are bright red to dark purple binoconvave disks without nuclei.
Theay are made in the red bone marrow of the skull. They originate as erythrocyte
stem cells in the red bone marrow. They function to transport O2 and CO2. The
red pigment hemoglobin protein allows the cell to acquire oxygen in lungs, and
give it up in the tissues.
- White
blood cells are larger, have a nucleus. And appear translucent. They are
divided into granular and agranular leukocytes. They are formed in red bone
marrow. They function to fight infection.
-Platelets
are fragments of megokaryocytes in red bone marrown. They function as to aide
blood clot or coagulate.
Circulatory
System- Heart Structure and Function
Identify
and give functions for each of the following :
a) Left
and right atria: upper chambers of the heart which receive blood
b) Left
and right ventricles: lower chamber of the heart which sends blood to the major
veins and arteries
c)
Coronary arteries and veins : serve the heart muscle itself. The coronary
arteries lie on the external surface of the heart where they become capillary
beds, venules and cardiac veins, which empty into the right atrium.
d) Anterior
and posterior vena cava: major vein connected to the right atrium, which carry
deoxygenated blood
e)
Aorta : major artery of the body, connected to the left ventricle, transports
blood to the systemic circuit
f)
Pulmonary artery and veins : part of the pulmonary circuit which transport
blood from/to the heart and lungs
g)
Pulmonary trunk : immediate artery after right ventricle. Branches into the
left and right pulmonary veins. Functions as to transport deoxygenated bloods
to the lungs in the capillaries.
h)
Atrioventricular Valves: supported by strong fibrous strings called chordate
tendiae, which support the valve and prevent them from inverting when the heart
contracts. They direct the blood flow and prevent its backward movement between
the atria and ventricles.
I)
Chordae tendinae :strong fibrous strings that support the atrioventricular
valve. It is attached to muscular projections of the ventricular walls.
j)
Semi-lunar valves : direct the flow of blood and prevent its backward movement
between the right ventricle and the pulmonary Turk, and the left ventricle and
the aorta.
k)
Septum : a wall inside the heart that separates the heart into a right and left
side.
Describe
the location and functions of the SA node, AV node and Purkinje fibers:
-
SA
node is found in the upper dorsal wall of the right atrium. It initiates the
heartbeat and automatically !
-
AV
node is found in the base of the right atrium very near the septum.The AV node
signals the ventricles to contract by way of large fibers terminating in the
more numerous and small purkinje fibers.
-
-Purkinje
fibers line the heart and cause the ventricles to contract.
Describe
autonomic regulation of the heartbeat by the nervous system :
The
autonomic system has two divisions : the parasympathetic system, and the
sympathetic system. The parasympathetic system causes the heartbeat to slow
down and sympathetic speed up. Factors such as the relative need for oxygen or
blood pressure determine which of these systems is activated.
Relate
factors that affect and regulate blood pressure to hypertension and hypotension
:
Hypertension
is systolic pressure , the lowest arterial pressure.
Hypotension
is diastolic pressure, the lowest arterial pressure.
