Connective tissue Flashcards
Give six functions of connective tissue + examples
provide substance and form to organs and body - adipose?
provide a medium for diffusion of nutrients and waste
- blood
attach muscle to bone and bone to bone - tendon and ligament
provide a cushion between tissues and organs
defend against infection
aid in injury repair.
give the components of CT
cells
extracellular matrix - with ground substance and fibres
what is embryonic connective tissue?
mesenchyme and mucous ct
describe mesencyme cells in mucous connective tissue
spindle shaped cells
tapering appearance
abundant viscou ground sub in extracellular matrix in large intercellular spaces
what makes up extracellular matrix?
fibres
ground substance
extracellular fluid
describe the structure of collagen
triple helix of alpha chains
periodic banding that repeats every 68nm
each collagen fibril is 200nm long and 1.5nm side
straggered collagen molecules adds to strenght
looks striated
can form collagen bundles
where can reticular fibres be found and describe appearance
in lymph nodes
spiderweb’y like a climbing frame
irregular network throughout node
lymphocytes are densely packed between fibres
may also see trabecular
lymph node capsule = collagen bundles
describe elastic fibres and where it can be found?
made of elastin surrounded by fibrillin
in lungs
in skin to return to original shape
artery walls
have amorphous appearance at low electron density
fibrillin microfibrils may look like projections at edge and darker areas within elastic fibres
which section is elastin present in the artery and aorta walls
tunica media
appears dark black/ dark purple squiggly lines with Gomori trichrome stain)
define connective tissue
a huge continuum throughout the body linking together muscle, nerve and epithetial tissue in a sturcutral way but also providing support in metabolic and physiological ways.
e.g. blood, cartilage and bone
Give differences between loose and dense connective tissues
DI - collagen is thicker and more abundant
DI- fewer fibroblasts
LCT - lots of non staining ground substance
Give some features of loose connective tissue
and where?
non staining extracellular matrix - v. viscous
many branches elastic fibres - loose arrangement of fibres
collagen fibres
blood vessels
fibroblast
mast cells
macrophages
adipocytes
loose CT - Adipose and Blood , subcutaneous tissue
lamina propria of cyrpts of L and in the submucosa of the colon / oesophagus
in mammary gland secreting tissue
can be in capsules around glands for protection , around blood vessels and nerves
Give features of dense irregular tissue
dense woven network of fibres bundles of collagen (some elastic fibres)
orientated in multiple directions - strength in all directions
viscous matrix
elastic fibres allow stretch and restoration
skin can then resist tearing forces
found in dermis of skin
joint capsules
muscle fascia, perichondrium, periosteum, dura mater
Give features of dense regular connective tissue
collagen bundles lie in parallel
densely packed formation
rows of elongated flattened fibroblasts lie between collagen bundles
in line with tensile force exerted on them
creates a very strong CT
in tendons
in a ligament collagen bundles are densely packed in parallel arrangement arragned in fascicles - separated by loose connective tissue endotendineum and peritendineum
look similar to skeletal muscle but fibres striated and more oval nuclei in muscle
describe function of fibroblasts
synthesises and secrete both ground substance and fibres collagen, elastic and reticular fibres such as procollagen
important in wound healing and formation of scar tissue
