Cardiovascular System Flashcards
(27 cards)
Explain the two circuit circulatory system.
The heart pumps blood into two separate circulatory:
Pulmonary Circulation - pumps deoxygenated blood to the lungs, then delivering oxygenated blood back to the heart.
Systemic Circulation - Pumps oxygenated blood from the heart to the rest of the body and back
Name the valves of the heart.
Right atrioventricular valve (tricuspid)
Left atrioventricular valve (mitral/bicuspid)
Pulmonary semilunar valve
Aortic semilunar valve
Name the chambers of the heart and their purpose.
Left and Right Ventricles - Muscular chambers that contract to pump blood out if the heart into the circulatory system.
Left and Right Atria - Muscular chambers that drain and squeeze blood into the ventricles.
Which veins feed into the right atrium?
Superior and Inferior Vena Cava
What cells are found in the heart?
Muscle (Myocardium) Conductive tissue Elastic tissue Fibrous Tissue Endothelium
What are the layers to the arterial wall?
Tunica Adventitia
Tunica Media
Tunica Intima
What are characteristics of the pulse?
Rate: 100 Tachy
Regularity: regular or irregular
Volume: Full/ thready weak
Define blood pressure.
Pressure exerted by the blood on the walls of the blood vessel measured in mmHG
What is systolic blood pressure?
Blood pressure when heart contracts.
What is diastolic pressure?
Blood pressure when heart is at rest.
What is stroke volume?
Volume of blood ejected from the ventricle on each contraction. Apporx 70mls in a normal adult.
What factors can affect the stroke volume?
Preload
After load
Contractility
Shape of ventricle
Define preload.
It is the load in the ventricle present before contraction has started.
What factors affect preload?
Venous return to the LV
Shape of ventricle
Volume of ventricle
Define afterload.
It is the pressure the ventricle has to generate to open the aortic or pulmonary valve.
What is cardiac output?
The volume of blood ejected from the heart pre minute.
What is the equation to work out cardiac output?
CO = HR x SV
Normally 4.5-5 L/min
What factors affect the afterload?
Amount of resistance to blood flow
- Elasticity of major arteries
- Constriction of smaller arterioles
What is peripheral/systemic vascular resistance?
The resistance to blood flow.
Define euvolaemia.
Normal, constant blood volume.
If passive transport occurs, which way do these ions moves across the cell?
- Potassium
- Sodium
- Calcium
Potassium - ?.. of the cell
Sodium - ?…the cell
Calcium - ?….. the cell
Define polarised state.
Resting phase in excitable cells
Define depolarisation.
Working state of an excitable cell causing contraction or conduction.
What is the pacemaker of the heart?
Sino-atrial node.
