Histology Flashcards
Smooth Muscle Hallmarks
no striations, gap junctions, occurs as bundles with elongated cells, NOT wavy like dense CT
Key proteins for contraction in smooth muscle
filaments that anchor to dense bodies (desmin and vimentin are the intermediate filaments), cells become globular and contract as one unit
Cardiac M. Hallmarks
short, branched cells with extensive capillaries and striations; intercalated discs and purkinje cells
What makes up the “intercalated discs?”
transverse junctions that interdigitate, often coincide with z lines
What are purkinje cells?
Modified muscle cells that act as a pacemaker, contain a lot of glycogen and mostly lack t-tubules
What types of fibers make up the epicardium?
dense fibrocollagenous CT with elastic fibers
What are some key features of myocardium?
striations, intercalated discs, diads, mitochondria, lipofusion and atrial granules
What are the three types of contacts in the myocardium?
fascia adherens (actin filaments), desmosomes, gap junctions
What is a diad?
T-tubule with 1 cisterna
What are atrial granules?
Granules that contain atrial natriuretic factor secreted by the right atrium
What is the endocardium made of?
Endothelium and loose CT, contains a subendocardial layer in the ventricles but not in the atria
What is the cardiac skeleton made of and what purpose does it serve?
irregular CT within the endocardium; anchors valves and maintains shape of AV canals, contributes to interventricular and interatrial septa, insertion of muscles and electrical insulator
What are the heart valves made of?
fibroelastic CT covered by endothelium
What is the conducting portion of the respiratory system responsible for?
warming, filtering, and humidifying air
What does the conducting portion of the respiratory system consist of?
nasal cavity, paranasal sinuses, nasopharynx, trachea, main bronchi, segmental and lobar bronchi, bronchioles
What is the function of the respiratory portion of the respiratory system?
gas exchange
What does the respiratory portion consist of?
respiratory bronchioles, alveolar ducts, and alveolar sacs
What are some key histological features of the larynx?
hyaline cartilage and some small elastic cartilages, nonkeratinized stratified squamous epithelium on the vocal folds
What is respiratory epithelium and what is it’s function?
Pseudostratified ciliated columnar epithelium, responsible for mucus production and transport
What are basal cells?
mitotically active stem cells in the respiratory tract
What are goblet cells and what do they secrete?
Modified columnar epithelial cells that synthesize and secrete mucigen granules
What are the four layers of the trachea?
Mucosa, submucosa, cartilaginous layer, and adventitia
What are some characteristics of the mucosa layer of the trachea?
resp. epithelium, goblet cells, lamina propria , BALT
What are the some key features of the submucosa in the trachea?
lots of submucosal glands
