General Connective Tissue x Flashcards
CT Characteristics
Separated - Surrounded by ECM Resident Cells & Wandering Cells Well-Vascularized Support Tissue Derived from Mesoderm
Resident Cells
Fibroblasts
Adipocytes
Wandering Cells
Macrophages Mast Cells Lymphoctyes Neutrophills wbc Eosiniphills wbc Basophils wbc
CT Fxns
Support frameworks and filler Transport of nutrients Storage of metabolites Defensive responses Tissue repair
Fibroblast - fxn, structure, other names
synthesis of CT fibers and ECM
Large, oval, pale nucleus
Chondroblast, Osteoblasts, Fibrocyte (inactive or quiescent)
Adipose Cells - types, characteristics/fxns
Unilocular, Multilocular Sensitive to neural and hormonal control Thermal Insulation Produces Leptin Shock absorbers Space filler 50-150un Surrounded by basal lamina - highly vasularized 15-25% body weight
Unilocular - name, fxn, structure
White - Adults, Storage of neutral fats (triglycerides), 1 lrg lipid droplet
Multilocular - name, fxn, structure
Brown - Newborns, Production of heat, numerous small lipid droplets
Hyperplastic, Hyperthrophic
increase in the overall number of cells.
Increase in the size of individual cells.
Leptin
Hormone that Inhibits appetite and stimulates metabolic rate
Macrophages - Characteristics/fxn
Part of mononulcear phagoctye system Immune response - antigen presentation Ingests particles w/ lysosomes Derived from blood monocytes Nucleus - oval or kidney shape
Specialized names for Macrophages + location
Histocytes Dust cells/Alveolar Macrophages - lungs Kupffer Cells - liver Microglia - neural tissue Osteoclasts - bone
Mast Cells - presentation, characteristics
Large, oval or elongate cells
bright purple (or pink) staining granules (basophillic)
Originate in bone marrow
Meditate inflammatory process, acute inflammation
Mediate immediate hypersensitivity reactions
Degranulation
Many IgE receptors on mast cell so binds IgE
IgE binds Ag –>–>–> Ca2+ release –> Mast granule fusion with plasma membrane and content release initiating inflammatory response.
Mast Cells release
Preformed mediators and newly systhesized mediatiors
Preformed mediatiors - def, types
released by mast cell granules Histamine Serine proteases Heparin Eosinophil chemotatic factor
Histamine - fxn
Increased capillary permeability = edema
Blood vessel dilation
in airways - increase mucus and smooth muscle contraction
Serine proteases - types, fxns
tryptase, chymase (role in angiotensis II production)
Heparin
sulfated GAG , anticoagulant
Newly synthesized mediators - def, types
Lipids and Cytokines made and released after mast cell activation and degranulation
- Leukotrines
- TNFalpha
- INterleukins
ECM components
ground substance
fibers
Ground substance - def/types
amorphous and viscous intracellular mixture of proteglycans, structural glycoproteins and tissue fluid
GAG - a.k.a, def
Glycosaminoglycans
long unbranched disaccarides with strong negative charge, attracts cations, attracts water, resist compression
Proteoglycans - def, fxn
GAG + protein core
attached via link protein to hyaluronic acid
Gel state in ECM - compression resistance
Barrier functions
Structural Glycoproteins - def, types/location
binds cell to ECM - cell adhesion, migration, signaling fibronectin - fibroblasts laminin - epithelial cells chonrocytes - chondrocytes osteonectin - bone
Fibronectin
from fibroblasts found in ECM
has binding sites for multiple components
Laminin
from epitihelial cells
found in basal lamina
binds to collage (type IV), intergrins, heparin, entactin
ability to cross link very well
Tissue fluid - from, fxn
derived from blood plasma
bound to neg. charge GAG
transports nutrients and wasted nu hydro-static and osmotic pressure.
Edema
abnormal increase in CT fluid
associated w inflammation, venous obstruction or starvation (fall in colloid osmotic pressure)
FIbers
Collagen
Reticular Fibers
Elastic Fibers
Collagen - staining, # types
Bifringent Inelastic stains pink w/ H&E stains blue w/ Mallorys trichrome 4 major types
Collage Type I - location, function
tendon, dermis, bone, ligaments, cornea, dentin
Tensile strength
Collagen Type II - location, function
cartilage, nucleus pulposus, vitreous body
Resistance to Compression
Collagen Type III - location, function
smooth muscle, vessels, fetal skin
Compliance - ability to change shape a little
Collagen Type IV - location, function
Basal Laminae
Support and filtration Barrier
Collage Type I - Cell types, Structure
Fibroblast
Fibers - large
Collage Type II - Cell types, Structure
Chondrocyte
Fibrils - small
Collage Type III - Cell types, Structure
Fibroblasts, ‘reticular’, smooth mucscle, schwann, hepatpcytes
Collage Type IV - Cell type, Structure
Epithelia, endothelium, Schwann, Muscle fibers
Fiber - layers
Molecules x Many = Fibrils x many = FIibers x many = Bundle
Reticular Fibers - characteristics, fxn
seen in type III collagen
Argyrophillic (silver staining)
only form fibrils and fibers
Provide support and change in shape
Elastic FIbers
provide stretch and recoil
Yellow appearance,
need special stains
Found in aorta
ECM interface - fxns, types
adhesion, communication and cell movements
Transmembrane structural glycoproteins
Basement Membrane
Transmembrane structural glycoproteins, - type, fxn
Intergrins and dystoglycans
Adhesion, traction and bidirectional signaling
Basement Membrane - layers
Lamina lucida, Lamina densa, Lamina reticularis
Can see with light microsope
Connective tissue classifiaction
Loose/ Areolar CT
Dense CT
Loose/ Areolar CT - def, arrangement, fxns
Grounds substance predominates Loose arrangement -Support epithelium -Lines body cavities -Ensheates blood vessels
Dense CT - def, fxn, types
fibers predominate
resist stress
Regular (tendon) and Irregular (dermis sclera)
Lamina Propria
Loose CT in mucosa
Regular Dense CT - arrangement
fibrillar components arranged in same direction
Irregular Dense CT - arrangement
FIbers are in mesh=like arrangement
Can be moved/ strong in more than one plane
Reticular CT - arrangement
mesh-like
Adipose CT
more cells than matrix (unlike other CT)
Elastic CT - arrangement
Sheets/Lamallae
Embryonic CT - def, types
Undifferentiatied CT
Mesenchymal
Mucoid
Messenchymal - characteristics
only in embyro
scattered fibers - spindle or start shaped
Mucoid - characteristics
Found only in umbilical coil
Loose amorphous
Hylauronic acid - gel state of ECM
