CVS Session 1 (Lecture 1.2) Flashcards
(46 cards)
Which arteries branch from the aortic arch?
1) Brachiocephalic
2) Left common carotid
3) Left subclavian
What does the pulmonary trunk bifurcate into? Where does it arise?
Arises from right ventricle and bifurcates into right and left pulmonary arteries.
Where does the aorta terminate? Which arteries does it turn into?
Abdominal cavity bifurcating into left and right common iliac arteries.
What do arteries do?
Carry blood away from the heart to capillary beds.
What property of the aorta allows it to maintain pressure during diastole?
Contain elastic fibres and smooth muscle cells which recoil giving back energy gained from systole.
In what fashion is blood pressure observed near the heart?
Pulsatile
What are the three major types of artery?
1) Elastic conducting
2) Muscular distributing arteries
3) Arterioles
What are the three layers of an artery and vein?
Tunica intima, Tunica media, Tunica adventitia
What makes up the Tunica Intima of elastic arteries
Endothelium and subendothelium of CT with discontinuous internal elastic lamina.
What makes up the Tunica Media of elastic arteries?
40-70 fenestrated elastic membranes. SMC and collagen between lamellae. External elastic lamina may be present
What makes up the Tunica Adventitia of elastic arteries?
Thin layer of fibroelastic CT containing vessels, lymphatic vessels and nerves
What special feature is within the Tunica Adventita of elastic arteries?
Vasa vasorum
What makes up the Tunica Intima of muscular arteries?
Endothelium, subendothelial layer. Thick internal elastic lamina
What makes up the Tunica Media of muscular arteries?
40 layers of SMC (conncented by gap junctions for coordinated contraction). Prominent external elastic lamina.
What makes up the Tunica Adventitia of muscular arteries?
Same as elastic but not as many vasa vasorum
What do the nerves do in the tunica adventitia?
Release of NA to stimulate vasoconstriction by acting on SMC in the TM layer. Gap junctions allow depolarisation of all cells.
What do protuding endothelial cells indicate?
Vasoconstriction
What is an end artery?
Terminal artery supplying all or most of the blood to a body part without significant collateral circulation. They undergo extensive branching without the development of channels connecting with other arteries.
Give three examples of an end artery and two anatomically true examples
1) Coronary artery
2) Splenic artery
3) Renal artery
Anatomically correct:
1) Central artery to the retina
2) Labyrynthine artery of the internal ear
If an artery has a diameter less than 0.1mm what is it known as?
Arteriole
How many layers of SMC do arterioles have in their TM ?
1-3
What is present in large arterioles but absent in all arterioles?
Internal elastic lamina present
External elastic lamina absent
Define a metarteriole..
Arteries that supply blood to capillary beds.
How do they differ from arterioles? What is the special term for the SMC in metarterioles?
SMC layer is not continuous. They are spaced apart and each encircles the endothelium of a capillary arising from the metarteriole.
Called a precapillary sphincter