Physio: Circulation of the Blood Flashcards
List the functions of the CV system
Bulk flow of materials to and from other systems Temperature regulation Homeostasis Host Defence Reproduction
Why are the left ventricular walls thicker than the right?
more power needed to overcome higher afterload in systemic circulation
What is the function of the microcirculation
It is the level at which blood flot to the tissues is regulated
What does parallel arrangement allow for
independent regulation of blood flow
what is the flow rate of blood through the heart
5L/minute
What part of the ANS predominantly controls vasculature
Sympathetic
What are the problems caused by blood flow in series
Blood flows from one system to the next, therefore flow cannot be adapted to suit needs of one system without affecting flow to systems before and after
Too much resistance to push blood through all organ systems
Inefficient
What does parallel flow allow for
Divergence of flow means each system has own mini circulation
Not dependent on flow through other systems
Allows adjustment of flow to suit metabolic needs without causing disturbance to other
what is meant by the path of least resistance?
increasing resistance will decrease flow to the area as blood chooses another route
what causes the biggest changes in resistance to blood flow
constriction of arterioles
at what point is the competence of a valve active
point of contraction
What valves are more likely to be damaged and why
Aortic and pulmonary
Smaller opening and higher pressure causes more stress and physical abrasion to the valves
What are the major differences of cardiac muscle compared to skeletal?
smaller fibres which individual nucleus
intercalated discs give branching network of individual cells
no need for fucntional syntium through gap junctions recruitment of cells for contraction
desmosomes give strong cell to cell adhesion
What % of CO is received by the brain
13%
what organ recieves approximately 430 ml/min of blood
skin
