Fechar
THE CARDIOVASCULAR SYSTEM:
functions to transport materials to and from cells. connects every cell in the body
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Pulmonary Circuit (LOW Pressure)
*Carries blood to and from the lungs for gas exchange.*
Systemic Circuit (HIGH pressure)
*carries oxygenated blood from heart to the rest of the body*
Heart <3
Pericardial Sac/Pericardium
The outer layer of the Pericardium
The inner layer of the pericardium
Heart Wall (3 Layers)
myocardium
heart anatomy
Coronary Sulcus
Interventricular Sulcus
Atria
Ventricles
Interatrial Septum
Connective Tissue Septum Separates muscles of atria and ventricles - why?
Fossa Ovalis
Auricle
Blood flow through heart:
BLOOD ENTERS via Right Atrium from:
Superior/Inferior Vena Cava + Coronary Sinus.
heart Valves prevent back flow of blood.
(AV ventricle to aorta, SL artery o heart)
(NO VALVES BETWEEN VEINS AND ATRIA)
How is the opening and closing of the valves controlled?
CORONARY CIRCULATION - how do we get oxygen and nutrients to the heart itself?
coronary arteries spread over the heart the Coronary Sinus brings deoxygenated blood back to the atria ...
Autorhythmic Fibres
(found in SA node, AV node, AV Bundle, Bundle Branches and Purkinje Fibres)
Contractile Fibres
Atria contract and relax together
Ventricles contract and relax together
Conducting System
Sinoatrial Node
Atrioventricular Node
Autorhythmic Cells
Sequence of Events
Criteria for Efficient Pumping
organised by intertribal pathway, internal pathway and AV nodal pathway
Cardiac Cycle
Electrocardiogram - summation of APs occurring in heart
end diastolic volume (EDV)
end systolic volume (ESV)
Stroke Volume (SV)
Most important factor in the Cardiac Cycle
Ejection Fraction
Cardiac Output (CO)
heart rate = autonomic innervation of the heart
Autonomic Tone
membrane potential
HORMONES
Atrial Reflex + Venous Return
Preload and Afterload
Blood Vessels
which is what? veins?
Arterial walls have three tunics:
Tunica Interna - Inner Tunic
Arterial Walls have three tunics:
Tunica Media - middle tunic
Arterial Walls have three tunics:
Tunica Externa - outer tunic
About Arteries
Muscular Arteries
Arterioles
Metarterioles
Capillaries
True Capillary
Continuous Capillary
Fenestrated Capillary
Sinusoidal Capillary
Venules
Veins have 3 tunics.
blood flow
Flow is proportional to change in pressure over resistance
Arterial Pressure
Pressure V Resistance
vascular resistance
peripheral resistance
Turbulence
Viscosity
Velocity of Blood Flow is Inversely Related to Cross Sectional Area
blood pressure measures pressures during ventricular contraction and relaxation
Diastole
systole
Venous Pressure & Venous Return
Venous Return
Capillary Pressure and Exchange Methods
Bulk Flow Capillary Exchange:
Hydrostatic Pressure
Osmotic Pressure
What does pressure do at the arteriole end of the capillary ?
What does pressure do at the venue end of the capillary?
Oedema
Homeostatic mechanisms maintain adequate blood flow to all tissues (PERFUSION)
Cardiovascular Regulation is regulated by Heart Rate and Stroke Volume
Autoregulation:
Vasodilators
vasoconstrictors
Autoregulation Homeostasis Example
Neural Mechanisms
Cardiovascular Centre
Proprioceptors
Baroreceptors
Chemoreceptors
Sympathetic Nervous System
Parasympathetic Nervus System
Baroreceptor Reflex
Sympathetic System
(can constrict or dilate vessels)
For vasodilation...
Sympathetic System
(can constrict or dilate vessels)
For vasoconstriction
Hormones & Cardiovascular Regulation
homeostatic mechanisms regulate cardiovascular activity to ensure adequate perfusion to tissues:
Over time, CV system changes with long term training
During Exercise
