Circulatory system
General outline
Blood vascular system
Heart
Arteries
Capillaries
veins
Lymphatic vascular system
Lymphatic capillaries
Lymphatic vessel
Lymphatic ducts
Capillaries
? LM
A single layer of endothelial cells
basement membrane
A few connective tissue (pericytes)
? EM
Continuous capillary
Fenestrated capillary
Sinusoid
Capillaries
Continuous C.
Fenestrated C.
Sinusoid
Continuous capillary:
? distributed in muscle tissue,brain,lung and
connective tissue,etc.
? endothelial cell,large number of pinocytotic
vesicles,no pores,exist cell junctions
between the endothelia
? basement membrane,integrity
Continuous
capillary
Fenestrated capillary:
? distributed in the kidney glomerulus,mucosa
of gastrointestine,some endocrine glands
? endothelial cells,present abundant pores,have
or haven’t diaphragm on them
? basement membrane,continuous
Fenestrated
capillary
Sinusoid:
? distributed in liver,spleen,and some
endocrine glands
? a greatly enlarged diameter
? endothelial cell,intercellular clefts are large
between cells,many pores without diaphragm
? absence of a continuous basement membrane
Sinusoid
Artery
? transport blood from heart to capillaries
? according to their size,structure
and function
Large artery
Medium-sized artery
Small artery
arteriole
are classified
Medium-sized artery:
? muscular artery
Tunica intima
Endothelium
Subendothelial layer,LCT
Internal elastic lamina,clear
Tunica media,contain 10~40 layers of circular
smooth muscle
Tunica adventitia External elastic laminaLCT,contain vasa vasorum
Medium-sized artery
Large artery:
? elastic artery
? subendothelial layer is thicker with a few
smooth muscles
? tunica media is thick,contains a lot of circular
elastic membrane
? internal and external elastic lamina are not
distinguished
? tunica adventitia are thiner
Large artery
Small artery:
? muscular artery and peripheral resistance
vessel
? internal elastic lamina is clear,while
external elastic lamina is not distinguished
? the media contains 3~9 layers of smooth
muscles
Vein
? large lumen,thin wall,irregular
? internal and external elastic lamina are not clear
? tunica media is thin,with a few elastic fibers and
smooth muscles
? tunica adventitia is thick
? some veins have valves
Heart
? a muscular organ that contracts
rhythmically
? pump blood through the circulatory
system
The wall of heart
? endocardium
Endothelium
Subendothelial layer
Subendocardial layer
? myocardium,thickest layer,consists of
cardiac muscle
? epicardium LCT,contain adipose tissue Methothelium
Impulse generating and conducting
system of the heart:
? Pacemaker cells,heartbeat generating
? Purkinje cells (bundle cell):
distributed in subendocardial layer,
larger than cardiac muscle cells
? Transitional cells,transmit impulse
Purkinje cell Cardiac cell
General outline
Blood vascular system
Heart
Arteries
Capillaries
veins
Lymphatic vascular system
Lymphatic capillaries
Lymphatic vessel
Lymphatic ducts
Capillaries
? LM
A single layer of endothelial cells
basement membrane
A few connective tissue (pericytes)
? EM
Continuous capillary
Fenestrated capillary
Sinusoid
Capillaries
Continuous C.
Fenestrated C.
Sinusoid
Continuous capillary:
? distributed in muscle tissue,brain,lung and
connective tissue,etc.
? endothelial cell,large number of pinocytotic
vesicles,no pores,exist cell junctions
between the endothelia
? basement membrane,integrity
Continuous
capillary
Fenestrated capillary:
? distributed in the kidney glomerulus,mucosa
of gastrointestine,some endocrine glands
? endothelial cells,present abundant pores,have
or haven’t diaphragm on them
? basement membrane,continuous
Fenestrated
capillary
Sinusoid:
? distributed in liver,spleen,and some
endocrine glands
? a greatly enlarged diameter
? endothelial cell,intercellular clefts are large
between cells,many pores without diaphragm
? absence of a continuous basement membrane
Sinusoid
Artery
? transport blood from heart to capillaries
? according to their size,structure
and function
Large artery
Medium-sized artery
Small artery
arteriole
are classified
Medium-sized artery:
? muscular artery
Tunica intima
Endothelium
Subendothelial layer,LCT
Internal elastic lamina,clear
Tunica media,contain 10~40 layers of circular
smooth muscle
Tunica adventitia External elastic laminaLCT,contain vasa vasorum
Medium-sized artery
Large artery:
? elastic artery
? subendothelial layer is thicker with a few
smooth muscles
? tunica media is thick,contains a lot of circular
elastic membrane
? internal and external elastic lamina are not
distinguished
? tunica adventitia are thiner
Large artery
Small artery:
? muscular artery and peripheral resistance
vessel
? internal elastic lamina is clear,while
external elastic lamina is not distinguished
? the media contains 3~9 layers of smooth
muscles
Vein
? large lumen,thin wall,irregular
? internal and external elastic lamina are not clear
? tunica media is thin,with a few elastic fibers and
smooth muscles
? tunica adventitia is thick
? some veins have valves
Heart
? a muscular organ that contracts
rhythmically
? pump blood through the circulatory
system
The wall of heart
? endocardium
Endothelium
Subendothelial layer
Subendocardial layer
? myocardium,thickest layer,consists of
cardiac muscle
? epicardium LCT,contain adipose tissue Methothelium
Impulse generating and conducting
system of the heart:
? Pacemaker cells,heartbeat generating
? Purkinje cells (bundle cell):
distributed in subendocardial layer,
larger than cardiac muscle cells
? Transitional cells,transmit impulse
Purkinje cell Cardiac cell
