Cardiac Histology Flashcards
Define cardiac muscle and smooth muscle in general terms
Cardiac - striated and involuntary
Smooth - non-striated and involuntary
What are smooth muscles connected with and what are their physiological purposes
Gap junctions which help spread the AP
How many nuclei do SM have
1
Smooth muscle are capable of doing what
Producing continuous contractions of low force
What do the thick and thin elements anchor to in SM
Cytoplasmic densities and dense bodies
SM contract in what way
As one unit and assume a globular shape
What are the dense bodies that anchor the filaments in SM made of
Desmin and vimentin
Define caveolae
The T-tubles of SM
Cardiac muscles are what 4 things
Short
Branched
Y-shaped
Contain extensive capillaries
The epicardium is lined with what and what is this made of
Mesothelium which is made up of simple squamous epithelium
What is the fibroud epicardium made of
Dense fibrocollagenous CT with elastic fibers
Where do intercalated disks sit and what is their purpose in myocardium
Always at Z-lines
Bind cells, transmit forces of contraction, and allow for the spread of AP
What are the two regions of the intercalated discs
Transverse region
Longitudinal region
What are the two parts of the transverse region and define them
- Fascia adherens - actin filaments at the ends of terminal sarcomeres which transmit contractile forces b/w cells. These are the most prominent
- Desmosomes - provide anchorage of the intermediate filaments of the cytoskeleton
What make sup the Longitudinal region and what is its function
Gap Junctions - sites for AP transfer
