LAB - Connective Tissue Flashcards
cells in connective tissue
- fibroblasts = synthesis and maintenance of ECM
- adipocytes
- defense cells = fixed: macs (histiocytes and mast cells) + wandering ( eos, neuts, basos lymphs)
ECM (extracellular material is composed;
- fibers = collagen, elastin
- ground substance
ground substance
- glycosaminoglycan
- have protein backbone w long chains of acidic carbs
- stains poorly on H&E
- clear spaces between cells and fibers
loose vs dense connective tissue
- loose = fibers orient in different directions
- dense = can form capsules like adrenal gland capsule
what does Masson trichrome stain for?
collagen fibers
muscles = red; RBCs = yellow
what does aldehyde fuchsin stain?
elastin = purple
what does Verhoeff/van Gieson stain?
black for elastin
red for collagen
RBCs, cytoplasm and muscle = yellow
lymph node capsule extends into tissue
trabeculae
pancreas capsule extenTIONS
SEPTAE = thinner than trabeculae and less prominent
all connective tissue, even specialized type cartilage develops from…
mesenchyme
functions of cartilage
- bears mechanical stress and weight
- provides surfaces for joints to slide on and absorb shock
- essential to long bone development
- gives support to soft tissue
chondroblasts vs chondrocytes
blasts = growth by apposition, grow and begin formation of ground substance and ECM; give rise to chondrocytes
chondrocytes = can divide (interstitial growth); maintain integrity of cartilage matrix
what is the matrix of cartilage made up of?
fibers (collagen; OR collagen and elastin)
ground substance = proteoglycans
NO vessels, nerves, or lymphatics
dense CT layer that covers cartilage
perichondrium
- essential for growth and maintenance of cartilage
three types of cartilage
hyaline, elastic, fibrocartilage
hyaline cartilage
- small aggregations of chondrocytes in an amorphous matrix composed of ground substance
- reinforced by collagen fibers
- found in nasal septum, larynx, sternal ends of ribs, tracheal rings
elastic cartilage
- composed of collagen and small bundles of elastin fibers in cartilage matrix
- external ear, epiglottis, larynx, Eustchian tubes
fibrocartilage
- transition b/w hyaline and dense connective tissue
- intervertebral discs, articular cartilages, pubic symphysis, joint capsules, ligaments, tendon
two processes by which cartilage grows
- interstitial: forms within cartilage; isolated chondrocytes divide to form a cluster with a max of eight cells; no directed blood supply to cluster
- appositional: at the periphery chondroblasts differentiate into chondrocytes, so the new cartilage is added at the surface
hyaline cartilage - chondrocytes embedded in amorphous matrix
looks like eyes! sitting in lacunae
