Ordinary Connective tissue Flashcards
What is all CT made up of?
Cells,fibres and ground substance
What are the 5 functions of CT?
Extracellular matrix that connects and binds organs and cells within the body
Gives support to the body
Facilitates cellular defence mechanisms
Repair
Provides an avenue for communication and transportation
How is CT supplied?
By blood and lymphatic vessels and nerves
What are the two types of CT?
Ordinary and special
What are the three types of ordinary CT?
Loose, areolar
Dense irregular
Dense regular
What are the 6 special CT?
Adipose tissue Cartilage Bone Dentin Haematopoeitic tissue Endothelium
What makes up the extra cellular matrix?
Fibres and ground substance
What type of cells are present in CT?
Fixed and wanderig
What type of fibres are present in CT?
Collagen
Reticular
Elastic
What is the ground substance of CT?
Highly hydrated gel
Glycosaminoglycans
proteoglycans
glycoproteins
What type of cell is a fibroblast and what is its functions?
fixed
ECM production
What type of cell is a mesenchymal and what is its functions?
fixed
CT precursor
What type of cell is a reticular cell and what is its functions?
fixed
production of reticular fibres
What type of cell is an adipocyte and what is its functions?
fixed
fat storage
What type of cell is a macrophage and what is its functions?
wandering
phagocytosis
What type of cell is a plasma cell and what is its functions?
wandering
antibody production
What type of cell is a mast cell and what is its functions?
Chemical mediators
What type of cell is a white blood cell and what is its functions?
wandering
defence
What is the principle cell of ordinary CT?
Fibroblast
What are fibrocytes?
Quiescent fibroblasts (resting)
What is the role of collagen?
Tough
Provides high tensile strength
Stretch resistant
most abundnat protein (25%)
What is the role of elastic?
Long thin fibres
allow for stretch and recoil
What is reticular fibres made from?
Type III collagen
What is the role of reticular fibre?
Branched, thin collagenous fibres
Form and extensive delicate networks
What is the role of Type I collagen?
Provides tensile strength, 90% of total collagen, dermis, ligaments, tendons, bone, dentin
What is the role of Type II collagen?
Found in hyaline and elastic cartilage
What is the role of Type III collagen?
Reticulin
What is the role of Type IV collagen?
Found in the basal lamina works with type VII
What is the role of Type VII collagen?
Forms anchoring fibrils works with IV
What is procollagen?
three individual collagen molecules combine within a cell
How is tropocollagen formed?
Procollagen is secreted from the cell and proteolytic enzymes cleave propeptides
What are tropocollagen molecules used for?
align to linear arrays to produce collagen fibrils
What are collagen fibrils for?
Assemble to form a collagen fibre - covalent cross-linking occurs
What is a collagen bundle?
Collagen fibres cominh together to form a a pink wavy structure (collagen bundles)
What is the main component of elastic fibres?
Elastin
What is the elastin core made up of?
Fibrils made up of the glyco protein fribrillin
What is the role of the ground substance?
Resists compressive forces on the matrix - provides mechanical strength
Functions as a molecular sieve through which nutrients, metabolites and hormones diffuse between blood capillaries and cells
What are glyosaminoglycans (GAG)?
Unbranched polysaccharide chains composed of repeating disaccharide units
What is the role of GAGs?
Maintains tissue architecture - rigidity and turgor provides structural integrity to cells and provides passageways between cells allowing for cell migration.
What is a proteoglycan molecule?
A GAG bound to a protein core
Give 4 examples of GAGs
Hyaluronic acid- wound healing
Keratan sulphate- bone and cartilage and cornea
Chondroitin sulphate- bone and cartilage and heart valves
Heparin Sulphate - basal lamina
What does areolar mean?
Open space
What is the role of dense irregular CT?
Adapted to offer resistance & protection
withstands tensions in different directions
Predominance of collagen fibres which run haphazardly
What is the role of dense regular CT?
Offer resistance in one direction or plane
Provide maximum tensile strength
Predominant collagen aligned to stress resist
What is the role of loose areolar CT?
holds structures in place
provides a packing framework for organ suppport
Whats is loose areolar CT made up of?
Collagen and fibroblasts abundance of ground substance
Where is loose areolar CT located?
below epithelia
forms the lamina propria of a mucosa
surrounds capillaries
What is dense irreagular CT made up of ?
collagen fibres densely packed and irregularly arranged
smaller proportion of Ground substance
Where is Dense irregular CT located?
Dermis
Submucosa of digestive tract
Periosteum & perichondrium
Fibrous capsules of organs
Where is Dense regular CT located?
Ligaments (Bone to bone)
Tendons (bone to muscle)
Aponeuroses
What adipose tissue composed of?
Adipocytes
What are adipocytes?
Fat cells - individual lipid droplet surrounded by thin layer of cytoplasm and nucleus
What is the function of adipose tissue?
Energy store, cushions, insulation
Metabolism or brown fat produces heat in the newborn
Where is adipose tissue found?
Under skin
around kidneys
within the abdomen
breasts
Where is the origin of CT?
Mesoderm