8.2 Blood Vessels Flashcards Preview

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Flashcards in 8.2 Blood Vessels Deck (12)
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What are some of the components in the blood vessels

Elastic fibres
Smooth muscle


What do the arteries do

Carry blood away from the heart to tissue of the body
Carry oxygenated blood


What artery carries deoxygenated blood

Pulmonary artery carries deoxygenated blood away from teh heart to the to the lungs


What is teh structure if the arteries

Walls contain elastic fibres smooth muscle and collagen
Elastic fibres enables them to withstand high blood pressure
Smooth lining so blood flows easily over it


What are arterioles

Link arteries and capillaries
More smooth muscle and less elastin
They can construct or dilate
Vasoconstriction and vasodilation


What are the capillaries

Microscopic blood vessels that link the arterioles with the venules
Form an extensive network
Small lumen, only 1 blood cell at a time


How are capillaries adapted for their roles

Provide a large enough surface area for teh diffusion of substances
Total cross-sectional area is always greater than teh arterioles supplying them so rate of blood flow falls
Walls are single endothelial cell thick so good for diffusion


What do veins do

Carry blood away from the cells of the body and towards the heart
Carry deoxygenated blood


What vein carries oxygenated blood

Pulmonary vein from lungs to heart
Umbilical vein from placenta to fetus


What is teh structure of veins

They don’t have a pulse
Low blood pressure
Have valves to prevent the back flow of blood
Walls contain lots of collagen and little elastic fibre
Vessels have a wide lumen and a smooth thin lining so blood flows easily


What are venules

Link capillaries to veins
Have very thin walls with just a little smooth muscle
Several venules join to form a vein


How does deoxygenated blood under low pressure made sure to get back to the heart

Majority of veins have one way valves
Veins run between the high active muscles in the body when they contract they squeeze veins
Breathing movements of the chest act as a pump