Lecture 5 - Connective Tissue Proper Flashcards
def: a matrix that links and supports other tissue types
connective tissue
what are the 2 main functions of connective tissue?
- structural support and organization
- metabolic support and transit
by volume, what does connective tissue consist of :
- few resident cells that are embedded in ECM
- protein fibers (collagen and elastin), ground substance
what are the 3 types of protein fibers in ECM?
- elastic fiber
- collagen fiber
- reticular fiber
def: more fibers, less ground substance, fewer cells
dense CT
def: few fibers, more ground substance, more cells (greater variety of cells)
loose (areolar) cells
def: found predictably in CT in stable numbers
fixed cells
def: enter connective tissue in response to a cue (infection or injury)
wandering/transient cells
def: immature cells, high division potential, multiple phenotypic fates, often produce and maintain ECM
-blasts
def: mature cells, lower division potential and more determined phenotypic fates
-cytes
def: often prune/remodel the ECM
-clasts
def: most numerous and critical cellular component of connective tissue, very common in loose CT and only cell of dense CT, large nuclei, abundant rER, surrounded by collagen
fibroblasts
def: synthesize collagen, elastic fibres, most carbohydrates of the ground substance, and reticulin
fibroblasts
what are fibroblasts nuclei like?
elongated, elliptical nuclei
what are fibroblast characteristics on EM?
- euchromatic nucleus
- prominent nucleolus
how are fibroblasts activated?
- by injury
- build basement membrane and sense tension
def: most abundant protein in the human body
collagen
def: type of collagen responsible for skin, tendon, vasculature, organs, bone
Type I
def: type of collagen responsible for cartilage
Type II
def: type of collagen responsible for reticulin, commonly found alongside Type I
Type III
what type of collage in the majority of collagen in the body?
Type 1, 90%
def: heterogenous group of inherited connective tissue disorders characterized by joint hyper mobility, cutaneous fragility, and hyperexternsibility
elhers-danlos sysndrome
def: CT in skin, aponeurotic fascia, tendons, ligaments, collagen fires are oriented in one direction and tightly packed, for maximum tensile strength
dense, regular connective tissue
def: modified dense CT that contains substantial amounts of elastin
elastin CT
