Intro to CVS Flashcards
Functions, cardiac output, systolic and diastolic, 4 types of blood vessels
What are the functions of the cardiovascular system?
1) Temperature regulation
2) Human reproduction
3) Transport of nutrients to tissue
4) Circulation of hormones and immune cells
5) Pump blood through lungs carry oxygen
Define passive diffusion and where it is ineffective
Random thermal movement of molecules
Ineffective in any distance greater than 1mm
Right atrium vs Left atrium
Right atrium receives deoxygenated blood from veins to the heart
Left atrium receives oxygenated blood from lungs to the heart
Right ventricle vs Left ventricle
Right ventricle pumps deoxygenated blood to the pulmonary artery which is connected to lungs
Left ventricle pumps oxygenated blood to aorta which is connected to whole body
What is systole and diastole
Systole- contraction
Diastole- relaxation
Define cardiac output
Volume of blood ejected from the heart per minute (5 litres/min)
Why are myocardium and brain vulnerable to stroke
They are poorly perfused, blood flow to these areas isn’t easily delivered, bloody supply easily cut off
What 3 factors determine cardiac output
1) Filling pressure
2) Parasympathetic or sympathetic nerves
3) Hormones/neurotransmitters
What is the equation for blood flow
(Pa - Pv)
Blood flow = ————–
Resistance
Why do capillaries have a large cross-sectional area
Slows down blood flow, more time for gas and nutrient exchange, more time to remove metabolic waste and form lymph
Why are arterioles resistance vessels
Arterioles are able to narrow, increasing arterial blood pressure, altering speed of blood flow
What does alpha-1 receptor do
Causes vasoconstriction
1) noradrenaline binds to a-1
2) a-1 coupled to Gq
3) Phospholipase C, PIP2, IP3, DAG
4) IP3, SR, Ca2+
What does Beta-2 receptor do
Relaxation (sympathetic, Gs)
What does Muscarinic 3 receptor do
Relaxation (parasympathetic, ACh, endothelial cells, NO)
