Week 4 - Blood Vessels and Systems Flashcards
What vessels are the majority of blood travelling in
The the venous system (veins)
Veins are called C__________ vessels
Capacitance vessels
Capillaries
Link between arterial and venous system
What is an important function of capillaries
Body temperature regulation
What happens to blood pressure and velocity as the total cross-sectional area increases
Decreases
What carries deoxygenated blood from the right ventricle to the lungs
Pulmonary arteries
What carries oxygenated from the left ventricle to the body
Circulatory arteries
Role of coronary circulation
Provide the heart muscle (myocardium) with oxygenated blood to enable function
2 coronary arteries
Right coronary artery (RCA) and Left coronary artery (LCA)
What does the RCA supply blood to
Right ventricle and atrium
What does the LCA supply blood to
Left ventricle and left atrium
The LCA splits into two branches, name these
Left anterior descending and Circumflex branches
Cardiac cycle
All mechanical and electrical events in one heart beat
Stroke volume (SV)
Volume of blood pumped out of the heart with each beat
Heart Rate (HR)
The number of times the heart beats per minute
Cardiac Output
Total volume of blood pumped out of the heart per minute
Equation for Cardiac Output
CO = HR x SV
Ejection fraction
The fraction of blood pumped out of the heart with each contraction
EF(%) = SV/EDV x 100 (blood left the heart / the maximum amount of blood it holds)
EDV (end diastolic volume)
Unit of measurement for CO
Litre per minute (L/min)
Resting Cardiac Output
~4.2 to 5.6 L/min
Females average CO
4L/min-1
Males average CO
5L/min-1
Why do males have a higher CO
The differences in body size
Systolic blood pressure
~120 mm Hg - Maximal pressure of blood against the arterials walls during systole (heart contraction; ventricle contraction)
Estimate of how hard the heart is working and strain on arterial walls during ventricular contraction
Diastolic blood pressure
~70-80 mm Hg - Pressure exerted by blood against the arterial walls during diastole (heart
relaxation; ventricle relaxation)
During relaxation (diastolic) phase of cardiac cycle, arterial blood pressure
decreases
Indicate peripheral resistance i.e. the ease with which blood flows from
arterioles into capillaries
