test 3 - CV system pt 3 Flashcards
where does the pulmonary circuit begin and end?
- starts at pulmonary trunk
- ends at left atrium receiving blood from pulmonary vein
where does the systemic circuit begin and end?
- begins at aorta
- ends at right atrium
what are the 3 layers of a blood vessel wall from superficial to deep?
1) adventitia
2) media
3) intima
blood vessel wall layer: adventitia
- superficial
- thick CT (mostly collagen, some elastin) that binds vessels to surrounding tissues
- thickest layer in veins
blood vessel wall layer: media
- middle
- smooth muscle and loose CT
- alters vessel diameter and BP (vasoconstriction and dilation)
- external elastic membrane
blood vessel wall layer: intima
- deepest
- endothelial lining and dilation of CT
- internal elastic membrane
what are the 3 types of arteries?
1) elastic
2) muscular (aka distribution)
3) arterioles
what are examples of elastic arteries?
- aorta
- pulmonary trunk and arteries
- brachiocephalic trunk
- subclavian artery
- common carotid and iliac arteries
elastic arteries - characteristics
- large lumen
- thick intima
- media has a lot of elastic fibres (high pressure)
- few myocytes (do not respond to SNS or local factors)
what are examples of muscular (aka distribution) arteries
- radial
- ulnar
- basilar
- popliteal
- brachial
- vertebral
- splenic
- renal
muscular arteries - characteristics
- moderate lumen
- media is thicker with many more myocytes (under SNS and local factor control)
- prominent internal elastic membrane
arterioles - characteristics
- small lumen
- only visible with a microscope
- thin adventitia
- media is 1-2 layers of myocytes
- control BF between arteries and capillaries
atherosclerosis - def
- build up of plaque in artery
- can cause angina or myocardial infarction if in coronary artery
what are the 3 types of capillaries?
1) continuous
2) fenestrated
3) sinusoids
which are our most common capillaries?
-continuous - found everywhere except epithelia and cartilage (need blood flow)