Anatomy of blood vessels Flashcards
1
Q
Blood vessel facts
A
- named mor either the specific part of the body they supply or an area surrounding that specific part
- veins and arteries generally share the same name (exceptions include sap heinous vein, vena cava, aorta)
2
Q
Artery
Vein
A
A: A vessel that carries blood away from the heart
V: A vessel that carries blood toward the heart
3
Q
Arteries
A
- elastic arteries: large number of collagen and elastin filaments in the tunica media, which gives it the ability to stretch in response to each pulse
- muscular arteries: medium-sized artery that draws blood from an elastic artery and branch into resistance vessels
- arteriales: small branch of an artery leading into capillaries
- metarteriole: short vessels that directly connect the arterioles and venules at opposite ends of the beds
4
Q
Capillaries
A
- true: branch from arterioles and provide exchange between tissue and
- continuous: endothelial cells provide an uninterrupted lining, and they only allow smaller molecules, such as water and ions to pass though their intercellular clefts (BBB)
- fenestrated: found in tissues where there is extensive molecular exchange with the blood such as the kidney, endocrine glands, small intestine. Pores that allow larger molecules through
- sinusoid: wide diameter and found in spleen, lymph nodes, bone marrow. Can be any of the 3 cap types above
5
Q
Veins
A
- venules: a very small vein, esp one collecting blood from the capillaries
- vessels tha carry blood toward the heart
- veins have thinner walls with less smooth muscle than arteries
- venous vessels increase in size as blood returns to the heart
Venules>small veins>medium veins>large veins>vena cava - larger veins below the heart have valves to prevent backflow
- pooling and clotting in veins can be a problem during prolonged mm inactivity, such as on a long airline flight
6
Q
Tunica intima
A
- Endothelium: in contact with blood and continuous with the endocardium lining of the heart
- Basement membrane
- Internal elastic lamina
7
Q
Tunica media
A
- muscular and connective tissue layer that helps regulate diameter of the lumen
- contains Nervi vasorum and vaso vasorum
- arteries and veins only
8
Q
Tunica externa
A
Helps anchor the vessels to surrounding tissue
9
Q
Pic
A
Pic
10
Q
Arteries
A
- the walls are thick, primarily from smooth muscle
- regulate blood pressure and shunt blood flow to where it is needed most
- the smooth muscle of arteries regulates blood pressure, distribution, and volume
- help propel blood onward while the ventricles are relaxing
- *main transporters of oxygenated blood
11
Q
Arterioles
A
- the smallest arteries
- carry blood from arteries to capillaries and regulate blood flow to specific capillary beds
- contain smooth muscle and can regulate blood flow
- *diameter is adjusted to regulate blood flow
12
Q
Capillaries
A
- blood flow through capillaries is call microcirculation
- thin walls allow for effective exchange of material between plasma and interstitial fluid
- most important vessels functionally because they allow the delivery and collection of substances
- exchange of oxygen, carbon dioxide, nutrients, and waste materials occur here (the other vessels are merely channels for the passage of blood)
- the body does not have a sufficient volume of blood for all capillary beds to be open at once
- capillaries do not contain smooth muscle, precapillary sphincters in arterioles serve to control blood flow into capillaries
- *diffusion occurs across thin walls
13
Q
Pic
A
Pic
14
Q
Pic
A
Pic
15
Q
Venules
A
Small blood vessels that collect blood from capillaries and join together to form veins
