Cardiovascular System 2 Flashcards
Vasculature
Blood vessels
Blood vessels 4 things they do…
🔸️Transport blood to tissues (gases, nutrients, and wastes are exchanged) and back to heart
🔸️Regulate blood flow to tissues
🔸️Control BP
🔸️Secrete chemicals
Pulmonary circuit transports blood from what part of the heart to where?
-transports blood from the heart (RV) to lungs
Systemic circuit transports blood from what part of the heart to where?
-transports blood from heart (LV) to the rest of body
Coronary circuit transports blood to where?
circulation of blood to myocardium
(coronary arteries & veins)
3 types of vessels
- Arteries
- Capillaries
- Veins
3 types of vessels: Arteries
🔸️distribution system of vasculature
🔸️Carry blood away from heart
3 types of vessels: Capillaries
- exchange system of vasculature
- smallest vessels
- Site of gas exchange
3 types of vessels: Veins
-collection system of vasculature
- Carry blood toward heart
3 basic layers or tunics of vessel wall:
Tunica intima
Tunica media
Tunica externa (adventitia)
Tunica intima
innermost layer
endothelial cells
Tunica media
middle layer
Smooth muscle
(VC and VD)
Tunica externa (adventitia)
Dense irregular CT
Vaso vasorum
Arteries 2 things about them?
-thicker tunica media reflects arteries’ role in controlling BP and blood flow
- more extensive internal and external elastic reflects arteries
are under much higher press.
3 classes of arteries
- Elastic (conducting) arteries
- Muscular (distributing) arteries
- Arterioles
Arteries:
Elastic (conducting) arteries
Where does it happen and what kind of pressure are they under?
🔸️aorta and immediate branches
🔸️highest pressure
Muscular (distributing) arteries
Well dev. tunica media of SMC
smaller diameter (named branches to organs)
Arterioles
smallest diameter
thin tunica media
(1-3 layers of SMC)
(Arterioles)
metarterioles
smallest arterioles that directly feed capillary beds
- precapillary sphincter SMC that encircles metarteriole-capillary junc.
Baroreceptors
(Arterioles)
pressure changes in aorta & common carotid artery
Chemoreceptors
(Arterioles)
-chemicals [O₂, CO₂, H+]
Veins
(6 things)
🔸️outnumber arteries
🔸️larger leumens
🔸️serve as blood reservoir (70% of total blood located in veins (systemic & pulmonary veins)
🔸️fewer elastic fibers
🔸️less SMC
🔸️thinner walls
Venules
(Veins)
- smallest veins; drain blood from capillary beds
Venous valves
(Veins)
prevent backflow of blood