Blood Vessels Flashcards
Arteries - what is Adventitia?
Provides structural strength and tethers the vessels in place. In large vessels the adventitia contains small blood vessels, the vaso vasorum (vessel of vessels)
Arteries - what is Elastin?
Gives vessels mechanical strength and their elastic properties (expand and recoil)
Arteries - what is Endothelium?
The endothelial layer is the filtering interface between the blood and the body. It also secretes various vasoactive products.
Arteries - what does Smooth Muscle do?
Supplies vessels with contractile power and regulates the diameter of the lumen.
Arteries - what does the Pre-capillary sphincter do?
Controls blood flow to specific capillary beds selectively
What is ‘active hyperaemia’?
The increase in blood flow according to the metabolic need of the tissue in question
What is flow autoregulation?
It is concerned with the maintenance of blood flow rather than changing it. When the driving pressure drops the vessels dilate, when it increases vessels constrict
Is the parasympathetic system involved in the regulation of arteriole pressure?
No - there is almost no involvement of the parasympathetic system so relaxation of arteries can happen by withdrawal of sympathetic stimulation.
Is the velocity of flow in capillaries HIGH or LOW?
Low
What is the main difference between lymph composition to plasma?
Lymph composition has a lower protein content.
What is Oedema?
The accumulation of excess fluid in the interstitial spaces (subcutaneous, abdomen, lungs)