1 - Structure And Function Of The CVS Flashcards
What three factors affect diffusion?
Area
Diffusion resistance
Concentration gradient
What are Venae Comitantes?
A pair of veins that accompany a small artery
Explain the ‘Supply and Demand’ concept of blood flow
Increased metabolism = increased metabolites and oxygen demand = increased blood flow
Why do we need resistance vessels (arterioles)?
Resistance is needed to regular blood flow, otherwise blood would only flow to the parts of the body easiest to perfuse
Why is capacitance important in veins?
Veins are able to store large amounts of blood because of their thin, distensible walls
This blood is used when to increase blood flow when needed
Blood flow is fastest where …
… cross-sectional area is smallest
What are the three types of arteries?
Elastic
Muscular
Arterioles
What is the general structure of vessels?
TAMIL Tunica Adventitia Tunica Media Tunica Intima Lumen
What controls vasoconstriction?
The sympathetic nervous system
- noradrenaline
What are pre-capillary spinchters?
Found in arterioles and metarterioles
Control flow of blood
Can be open and closed
What is the structure of a capillary?
Endothelium and basement membrane
What are the three types of capillaries?
Continuous
Fenestrated
Sinusoidal
What are the different structures in the venous system?
Post capillary venules
Venules
Veins
What is the significance of valves?
Ensure blood flows in one direction
Work with muscle contraction to propel blood to the heart
What are the two types of muscle found in large arteries?
Longitudinal - tunica Adventitia
Circular - tunica media
