Connective Tissue Flashcards
what are the types of fibers in connective tissue?
collagen fibres, reticular fibres and elastic fibres
what is the most dominant fiber type in connective tissue?
collagen fibers
what is the primary function of collagen fibers?
to provide strength and support
what are collagen fibers composed of?
regular arrangement of microfibrils made of tropocollagen (triple helix)
what are coarse collagen fibers formed by?
type I collagen
what are reticular fibers made of?
type III collagen
function of reticular fibres?
Reticular fibres are very delicate and form fine networks instead of thick bundles
Reticular fibres give support to individual cells
what are elastic fibers composed of?
elastic fibres consist of individual microfibrils, which are embedded in an amorphous matrix
where is ground substance found?
in all cavities and clefts between the fibres and cells of connective tissues
what is in ground substance?
its main structural constituent are proteoglycans however water, salts and other low molecular substances are also found
what causes ground substance to be viscous?
proteoglycans
what are proteoglycans?
proteins (~5%) and polysaccharide chains (~95%), which are covalently linked to each other
what is the dominant glycosaminoglycan in connective tissue?
hyaluronic acid
what cell type synthesizes the ground substance and fibers
fibrocytes
types of connective tissue cells?
fixed (fibrocytes and fats) and wandering (WBCs)
what happens to a fibrocyte when tissues are damaged?
fibrocyte is transformed into a fibroblast, which contains large amounts of the organelles which are necessary for the synthesis and excretion of proteins needed to repair the tissue damage
what is the endocrine function of an adipocyte?
they secrete the protein leptin which provides brain centers which regulate appetite with feedback about the bodies fat reserves.
what function do mast cells have?
they discharge histamine and heparin from vesicles if they come in contact with antigens which causes vasodilation
what are plasma cells?
lymphocytes that produce antibody
what is dense connective tissue?
completely dominated by fibres, can be regular (ligaments, tendons) or irregular (skin)
what does reticular connective tissue form?
the structural framework in which the cells of the organ are suspended
what type of tissue functions in lipid storage?
white adipose tissue
when is brown adipose tissue formed?
in a newborn
what tissue type forms the filling of the early embryo?
Mesenchymal connective tissue which has stem cell properties
