Histology pt 2 Flashcards
Connective tissue
Consists of cells and extracellular matrix
Extracellular matrix
3-dimension network consisting of extracellular molecules and minerals such as proteins, glycoproteins, proteoglycans, minerals and hydroxyapatite providing structural and biochemical support to surrounding cells and tissue.
Non fibrous components
Ground substance
Glycosaminoglycans
Glycoproteins and proteoglycans
Ground substance
Amorphous gel-like substance in extracellular space. Composed of water and large organic molecules. Involved in movement of tissues and metabolism. Provides lubrication for fibrous component of ECM
Glycosaminoglycans
polysaccharides that trap water, giving the ground substance a gel-like texture
Glycoproteins and proteoglycans
modified proteins that have oligosaccharide or polysaccharides attachments. Give ground substance structure
Areolar tissue structure
loose, fluid-like
Allows movement of cells - ^GS
Tendon structure
Dense
Providing strength
Decreased GS
Collagen fibres
long and unbranched, flexible and provide strength to tissue
Reticular fibres - collagen and function
Consist of collagen but are thinner and branched, forming a strong but flexible structure
Found in organs where they provide structure to the organ but allow movement of cells
Elastic fibers
Made up of elastin and are branched and allow tissue to stretch up to 200% original shape
Loose connective tissue - Areolar
-Thin collagen fibres
- Reticular fibres
- Elastin fibres
Holds organs in place and provides cushioning. Attaches epithelial tissue to underlying tissue and allows cell movement e.g phagocytic cells which provide defense against pathogens
Loose connective tissue - Adipose tissue
-Reticular tissue
- Collagen III
-High GS
Provides cushioning, insulation; stores energy.
Obesity in cells
increased GS which leads to increased PG. PG bind to inflammatory/immune cells and increase inflammation which leads to a metabolic disease
Loose connective tissue - Reticular
Collagen III
Increased GS
Fibres from a supporting skeleton for organs and allows movement of cells and fluids
Dense connective tissue - dense regular
Collagen I
1-2% elastin
decreased GS
Provides firm attachment, provides strength
Dense connective tissue - dense irregular
Collagen I
2-4% elastin
decreased GS
Provides strength, resistant to forces from different directions
Hyaline cartilage
Collagen II
- fibrous network that holds the GS
- increased PG, glycoproteins and water
Reduces friction, allows for compression, provide flexible support
Elastic cartilage
Collagen II
Elastin
Decreased GS
Provides support and flexibility, allows tissue to distort but return to original shape
Fibrocartilage
Collagen I & II
Decreased GS
Resists compression, provides cushioning
Bone
ECM made up of hydroxyapatite and collagen.
Hydroxyapatite - strong by inflexible, can withstand compression but not bending, twisting
Collagen - tolerated bending and stretching but not compression, provide a framework for the formation of hydroxyapatite crystals
Canaliculi function
Produce ECM molecules
Compact bone
Made of osteons. Protection and strength
Spongy bone
Made up of trabeculae, save weight
Woven bone
Fibrous bone
Haphazard arrangement of collagen and is weak unlike the lamellae of osteon or trabeculae. Formed during development and replaced by lamellar bone
Collagen III is in
Reticular and adipose tissue
Collagen II is in
Hyaline cartilage, articular cartilage and fibrocartilage
Collagen I is in
Dense irregular, dense regular and fibrocartilage
