Heart Histology Flashcards
What is the histological appearance of purkinje fibres?
pale with a very pale/clear centre
What is the fibrous pericardium?
sac of tough fibrocollagenous connective tissue
What s the structure of contractile cardiac muscle fibres?
single nucleus, intercalated discs
What is the parietal serous pericardium?
lines inner surface of the fibrous pericardium
What is the histological appearance of pacemaker cells?
pale due to the small number of organelles within them
What is the role of the pericardial cavity?
contains serous fluid which provides lubrication for heart movement
What is the structure of purkinje fibres?
larger than contractile cardiac myocytes, located in the subendocardial layer, abundant glycogen, no T-tubules, no intercalated discs, sparse actin and myosin filaments
What is the visceral serous pericardium?
covers the surface of the heart
What is the structure of the pacemaker cells?
smaller than contractile cardiac myocytes and embedded in a more extensive matrix of connective tissue, few irregularly arranged myofibrils, little glycogen, no proper T-tubule system
What is the structure of the serous pericardium?
simple squamous epithelium backed by basal lamina and connective tissue
How do the purkinje fibres distribute excitatory activity?
so that the ventricles contract from inferior to superior
What is the role of the chordae tendinae?
anchor AV valves leaflets to papillary muscles
What is the structure of the epicardium?
single layer of flattened epithelium called the mesothelium, basal lamina, fibroelastic connective tissue, adipose tissue in some places into which coronary vessels re embedded
What is the role of the fibrous skeleton?
supports the valves, provides attachments for cardiac muscle fibres, electrically isolates the atria from the ventricles
What is the function of the subendocardium?
contains small blood vessels, nerves and branches of impulse conducting system
