H: CVS Flashcards
Layers of blood vessels
- Tunica intima (inner)
- Tunica media (middle): made of elastic tissue + smooth muscle. Elastic tissue allows for stretch + recoil, smooth muscle allows for vasodilation + vasoconstriction.
- Tunica adventitia (outer): has collagen for strenght + protection.
Heart wall layers
- Epicardium (tunica adventitia): visceral serous pericardium
- Myocardium (tunica media): cardiac muscle.
- Endocardium (tunica intima): inner lining
Cardiac cell structure?
Cells of cardiac muscle are tubular and branching.
Role of elastic laminae in connective tissue of tunica media:
- Allows wall of blood vessel to expand + bulge and accommodate blood
- Elastic recoil helps propel blood
- Reduces pressure fluctuations
Tunica media
- Mainly smooth muscle –> highly contractile
- Elastic fibres are confined to inner and outer sides of tunica media (Internal + external elastic lamina)
Metarterioles
large diameter capillaries with some muscle in wall
Precapillary sphincter
at origin of capillary
Arterio-venous shunts
pathways go through arteriole to venule.
Pericytes
around capillaries and are used for contraction.
Types of capillaries
- Continuous endothelium
- Fenestrated endothelium (has pore)
- Discontinuous endothelium (have large holes)
Fenestrated capillaries location
found in SI mucosa, endocrine glands, renal glomeruli.
Discontinuous capillaries location
found in liver, spleen, bone marrow.
Have discontinuous basement membrane.
Veins structure
- Thinner walls: larger lumens than arteries - Tunica adventitia is the thickest layer
- Tunica intima has valves
Cause of varicose veins
Backflow from veins can cause varicose veins.
Identify
type of tissue + letters
Continuous epithelium (capillary)
E = complete lining of endothelial cells
EC = endothelial cytoplasm
BM = basement membrane
C = collagen fibrils
P = pericyte
BMp = BM of pericyte
Identify type of tissue + letters
Fenestrated epithelium (capillary)
EC = endothelial cytoplasm
F = pores
Identify (LM of LV wall)
P = Epicardium
M = Myocardium
E = Endocardium
PM = Papillary muscle
Identify (elastic artery in aorta)
I = tunica intima
M = tunica media
A = tunica adventitia
Identify (LM of epicardium)
Me = flat monolayer of mesothelial cells
F = sheet of fibrocollagenous tissue with elastic fibres
CA = large branch of coronary artery
A = adipose tissue in areas with arteries
M = myocardium with small artery
Identify (LM of myocardium)
Identify (LM of endocardium)
Identify (muscular artery)
Identify (musclar artery)
IEL = internal elastic lamina
M = tunica media
EEL = external elastic lamina
A = adventitia
Identify (2 arterioles)
M = tunica media
E = endothelial cells
Identify (microcirculation)
V = venule
C = capillary network
Ma = metarterioles
S = Arterio-venous shunts
At = arteriole
Identify (capillary)
E = single layer of flattened endothelial cells
P = pericytes
Identify (large vein)
Identify
Identify (medium sized vein)
M = tunica media
A = tunica adventitia
Identify (vein with valve)
L = leaflet
Identify (large muscular vein)
M = tunica media
A = tunica adventitia
