Blood Vessels Flashcards
1
Q
Three layers of the vessel wall
A
- Tunica interna
- Tunica media
- Tunica externa
2
Q
Tunica interna
A
Composed of endothelium and thin layer of connective tissue
3
Q
Tunica media
A
The thickest layer composed of elastic fibers and smooth muscle
4
Q
Tunica externa
A
Composed of connective tissue
5
Q
Elastic (conducting) Artery
A
- Largest diameter arteries
- Thick tunica media that can stretch and recoil w/ heart
6
Q
Muscular (distributing) Arteries
A
- Medium-sized arteries that distribute blood to skeletal muscles and internal organs
- Tunica media contains mostly smooth muscle
- Able to vasoconstrict and vasodilate
7
Q
Arterioles
A
- Small to microscopic vessels with a poorly defined tunica externa (thin walls)
- Tunica media is composed of smooth muscle cells
- Delivers blood to capillaries
- vasodilate/vasoconstrict to regulate blood pressure
8
Q
Capillaries
A
- Smallest blood vessels
- Connect arterioles to venules
- Allow for exchange between blood and surrounding tissues/cells
- Walls are one-cell width
9
Q
Veins
A
Collect blood from organs and tissues and return it to the heart
10
Q
Venules
A
- Smallest veins
- Collect blood from capillaries
- Wall composed primarily of tunica interna
- Venules converge to form veins
11
Q
Medium and Large Veins
A
- Tunica externa is the thickest layer because
of ‘milking action’ - Formed by merged venules
- Carry blood back to the heart
12
Q
Valves in the walls of veins
A
- prevent backflow of blood
- venous compression (contraction of adjacent muscles) maintain blood flow
13
Q
Lymphatic Vessels
A
returns excess extracellular fluid to blood vascular system
14
Q
Largest Arteries
A
- Aorta
- Pulmonary Artery
15
Q
Minor Arteries
A
- carotid artery (head/neck)
- subclavian artery (arm/hand)
- abdominal aorta (abdominal organs)
- iliac artery (pelvic organs)
- femoral artery (thigh)
