Histology Flashcards
Basic layer structure of blood vessels?
tunica intima (inner) internal elastic membrane tunica media (middle) external elastic membrane tunica adventitia (outer)
tunica intima of blood vessels is made of?
simple squamous endothelium + thin layer CT
tunica media of blood vessels is made of?
predominately smooth muscle (very variable thickness)
tunica adventitia of blood vessels is made of?
supporting CT
Big arteries have?
lots of elastic tissue in tunica media to allow pumping and recoil
arterioles are made up of?
tunica intima
tunica media with 1 or 2 layers smooth muscle
almost no adventitia
capillaries are made up of?
endothelial cells + basal lamina PLUS pericytes (CT cells with contractile properties)
what are the types of capillary?
continuous
fenstrated
discontinuous/sinusoidal
veins are made of?
tunica intima
thin tunica media (lot thinner than arteries as only few layers smooth muscle)
adventitia (thick in larger veins)
valves in veins are made of?
inward extensions of tunica media
lymphatics are thin or thick walled?
thin
lymph nodes are for?
immunological surveillance
how is flow established in lymphatic vessels?
NO pump
smooth muscle in walls PLUS hydrostatic pressure in tissue PLUS compression of vessels by voluntary muscle PLUS valves
the heart is made up of which 3 layers?
endocardium (inner)
myocardium
epicardium (outer
endocardium does what?
lines entire inner surface of heart inc valves
endocardium is made up of what?
endothelium + basal lamina + thin layer of collagen fibres + dense CT (sometimes subendocardium)
where is the subendocardium located?
between the endocardium and myocardium
what does the subendocardium contain?
loose CT with small blood vessels, nerves and the conducting system
what does the myocardium contain?
contractile cardiac muscle + individual muscle fibres surrounded by collagneous CT with lots of capillaries
what is the epicardium made of?
mesothelium (flattened epi) + basal lamina + CT + adipose tissue
in which layer are coronary arteries embedded?
in adipose tissue of the epicardium
what is the pericardium made up of?
fibrous pericardium serous pericardium (visceral and parietal)
what is the fibrous pericardium made of?
tough fibrocollagenous CT
what is the serous pericardium made of?
mesothelium + basal lamina + CT
what is the function of the fibrous skeleton of the heart?
support valves
provide attachment for myocardium
non-conducting so isolates atria from ventricles
what is the fibrous skeleton made of?
thick bands of CT
what are the heart valves made of?
outer endo + basal lamina + collagen and elastin fibre layer + lamina fibrosa (core of dense CT continious with fibrous skeleton)
which heart valves are anchored by papillary muscles?
tricuspid and mitral
what holds the leaflets of the valves to the papillary muscles?
chordae tendineae
do heart valves contain blood vessels?
no
3 types of cardiac muscle cells are?
contractile
pacemaker
conducting
name 3 characteristics of pacemaker cells
Much smaller than contractile muscle cells
Appear pale
Have few myofibrils as not made to contract
Name 2 characteristics of conducting cells
Larger than contractile cardiac muscle cells
Pale with clear centre
where are pacemaker cells found?
Embedded in extensive CT
where are conducting cells found?
subendocardial layer just deep to endocardium
