Cardiovascular Flashcards
blood vascular system
A closed supply and drainage system - continuous loop
Lymphatic system
A open entry drainage system - a one way system
Pulmonary circulation
Heart - lungs
Systematic circulation
heart - body
Right side of hearts job
Pumps blood to lungs
Left side of hearts job
pump oxygenated blood to the muscles (systemic circulation)
What is the supply side of the CVS
Arteries - carry things away from heart
What is the drainage side of CVS
Veins and lymphatics
What does the exchange network consist of
Capillaries
- continuous (controlled, tight)
- fenestrated (leaky)
- Sinusoidal (very leaky)
How is the heart positioned within the chest
turned to left and rotated anteriorly
Which ribs does the heart sit between
base - between 2 and 3
Apex - between 5 and 6
Where can the PMI (point of maximal impulse) be felt
it can be felt from the apex between the 5th and 6th ribs at the midclavicular line
What separates the right and left sides of the heart
Inter-ventricular septum
What veins return to the right atrium
Superior vena cava
Inferior vena cava
Coronary sinus
What lungs return to the left atrium
Four pulmonary veins (2 right and 2 left)
Layers of heart wall from inner to outer
Endocardium - myocardium - epicardium - pericardium
Endocardium
Innermost layer
simple squamous epithelium
Loose irregular FCT
small blood vessels
Purkinje fibres
Which side of the heart has thicker myocardium and why
Left side - has to pump blood all over the body so need more muscle
Volume same, pressure different
Myocardium
Muscle layer of the heart
What does the epicardium contain
bLOOd vessels and loose irregular FCT, adipose
side note: its the outermost layer excluding pericardium
tWO MAIN components of the pericardium
Fibrous (outer) and serous (inner)
AV valve on left side of heart
Bicuspid
AV valve on right side
TRIcuspid
Function of semilunar valves
prevent blood returning into ventricles during filling
Function of AV valves
Prevent blood flowing back into atrium during ventricular contraction
What do the AV valves require to control shutting
Chordae tendineae and papillary muscles
What are the names of the heart arteries
Coronary arteries
- right - runs in right coronary groove
- left - runs in left coronary groove
- circumflex
- Anterior interventricular
What are the names of the heart veins
Cardiac veins
- coronary sinus (drains into the right atrium)
- great cardiac vein
- small cardiac vein
What links actin to actin in cardiac muscle cells
Adhesion belts
What links cytokeratin to cytokeratin in cardiac muscle cells
Desmosomes
What allows for electrochemical communication in cardiac muscle cells
Gap junction
What is the conduction system of the heart responsible for
it’s actions greatly increase the efficiency of heart pumping
responsible for the coordination of heart contraction and of atrioventricular valve action
aUTONOMIC NERVES ALTER THE RATE OF CONDUCTION impulse generation
Name the major arteries and veins from the heart to the foot and back
Ascending aorta - aortic arch - descending aorta - thoracic aorta - abdominal aorta - common iliac artery - external iliac artery - femoral artery - popliteal artery - posterior tibial artery - planter arch - capillaries - deep pathway(plantar venous arch - posterior tibial vein - popliteal vein - femoral vein) or superficial (great saphenous vein) - external iliac vein - common iliac vein - inferior vena cava
layers of the blood vessels (from inner to outer)
Tunica intima, tunica media, tunica adventitia
Layers of the tunica intima
Endothelium - simple squamous epithelium
sub-endothelium - a sparse pad of loose FCT
Internal elastic lamina - condensed sheet of elastic tissue
Role of the endothelium in tunica intima
prevent blood from clotting within the vessel
tunica media
Smooth muscle
thickness proportional to vessel diameter and blood pressure the higher the pressure the thicker the media.
produces vasoconstriction
Tunica adventitia
Loose fibrous connective tissue
high collagen
has vasa vasorum in ones that need it
Arterioles
the resistance vessels of the circulation - determine blood pressure
Capillaries
site of exchange between blood and tissue
Venules
The smallest veins between capillaries and veins
Which layer is often the thickest in the veins
Adventitia
What is the thickness of the media in veins relative to arteries
much thinner
What is the thickest layer of arteries
Media
comparison between veins and arteries
veins have wider blood pathway so that they can carry the same amount of blood
Arteries have thicker wall to increase the pressure
What do valves in the veins do
Only let the blood go one way
wHERE would you find a more elastic artery and a more muscular artery
Muscular - further away from heart
Elastic - close to heart
What are the three capillary characteristics
Thin walls
Large total Cross sectional area
Slow and smooth flow rate - cause walls can’t hold pressure, if too fast not enough time
RBC and capillary function
The capillaries have a diameter of 8-10
RBC and capillary function
The capillaries have a diameter of 8-10
RBC and capillary function
The capillaries have a diameter of 8-10
RBC and capillary function
The capillaries have a diameter of 8-10um due to this being the size of RBC which is so they they are close to the surrounding tissue and can optimise the rate of diffusion
wHAT are capillaries made up of
single endothelial cells
Where are continuous capillaries found
areas of the bidy where what leaves and enters has to be tightly controlled
Where are fenestrated capillaries found
Where movement of fluid and molecules occurs quickly in large volumes
What is the function of sinusiodal capillaries
to allow the plasma to pass into surrounding tissues without RBC’s
What are capillaries surrounded by
a basement membrane
Lymph vessels characteristics
Thin walled
No RBC
valves
Where does lymph vessels link up to at the heart
upper right side - The right lymphatic duct drains into subclavian vein
the left side and lower right - The thoracic duct goes into left subclavian vein
Where does fat from the GI tract go
lacteals - cisterna chyli - venus system
Diastole
Relaxing
falling pressure
Systole
contraction
risking pressure
5 Main phases of cardiac cycle
Arterial systole, isovolumetric contraction, ventricular ejection, Isovolumetric relaxation and passive filling
Hyper tension
high blood pressure
Hypotension
Low blood pressure
Difference between electrical and contractile cells
Contractile contains high actin and myosin causing a striated appearance
Electrical cells contain low actin and myosin cause a pale striated appearance
flow=
pressure/resistance
Q=P/R
Mean arterial pressure =(in relation to flow)
Q X R
MAP =(in relation to CO)
CO x TPR
CO =(in relation to stroke volume and HR)
= SV X HR
What are Baroreceptors
Blood pressure sensors
- they are stretch receptor
What are the 2 baroreceptors
Aortic arch and carotid sinus
What is the vagus nerve
The parasympathetic nerve travelling from the spinal cord to the heart
What nerve travels through the sympathetic trunk ganglion
The sympathetic cardiac nerve which travels to the heart
What is the resistance equation
1/r^4
Where is most blood stored
Systemic venous system
Compliance
change in volume/change in pressure
how much the vessel will deform in response to applied force
Starlings law of the heart
the more stretched muscle fibres are before a contraction the stronger the contraction will be.
General functions of blood
transport, immune, coagulation
Hematopoiesis
the formation of blood cells
Where is haematopoiesis initiated
In red bone marrow which contains haemocytoblasts
What sre the progenitors for all blood cells
Hemotoblasts - blood stem cells
What does EPO do?
Its a chemical that tells stem cells to make more RBC
