Connective Tissue 1: Connective Tissue Proper Flashcards
What is the origin of all connective tissue?
The mesoderme
What are the types of connective tissue?
Proper
Cartilage
Adipose
Bone
Blood
What are the three permanent cells of proper connective tissue?
Les mastocytes
Les fibroblastes
Les adipocytes
What are the properties of fibroblast?
Main cells of the conjonctif proprement dit
Thin cells with long cytoplasmic extension
They are the Synthesis site for the composants of the extracellular matrix.
They do not have a lame basale
In proper connective tissue, what creates the extracellular matrix?
fibroblast
What is a rest state for fibroblasts?
When the secretion activity of a fibroblast stops, its cytoplasm contracts and its nucleus condense, resulting in only the spindle-shaped nucleus detected in histological preparations (cannot tell the difference).
This phenotype is called the fibrocyte.
What are Myofibroblast?
Contractile Phenotype of fibroblast
Myofibroblasts are important in the repair of injuries and wound healing.
TRUE or FALSE, Proper Connective tissue contains adipose tissue.
FALSE,
Connective TIssue Proper contains some adipose cells
Here we must remember that they are only part of the connective tissue. This is not to be confused with adipose tissue (see below).
What is the role of adipose cells in connective tissue proper?
Synthèse des lipides (liposynthèse)
Réserve d’énergie à long terme (triglycérides)
Libération des lipides sous forme d’acides gras (lipolyse).
What are the two types of adipose cells in connective tissue proper and their roles?
Adipocytes Blanc
Réserve énergétique
Isolant thermique
Amortisseur de chocs
Adipocytes Bruns:
très riche en mitochondries -> brown color
It is not functional in adults:
Only in new-borns
Can become active in adults in extreme conditions.
What is the role of mastocyte cells in connective tissue proper?
cellules de surveillance et de signalisation ».
Cytoplasme riche en granulations basophiles
Important for reactions in allergic and inflammatory reactions:
What are the transitory cells of connective tissue proper?
Macrophages
Leucocytes,
plasmocytes
Role of macrophages in connective tissue proper?
They will phagocyte:
Non-selectively
Also will recycle red blood cells
Can you identify Leucocytes in connective tissue proper?
Low % in the connective tissue so we cannot really identify them but we can identify Lymphocytes
What are plasmocytes in connective tissue proper?
lymphocytes B activés
Synthétise et sécrète des anticorps
What does the extracellular matrix consist of in connective tissue proper?
Des fibres (collagène, élastine)
Substance fondamentale
Where does collagen come from in connective tissue proper?
It comes from fibroblasts
What is the smallest unit of collagen?
tropocollagène -> microfibrille → fibrille → fibre
What are the 4 types of collagen and their usual location?
Type I (grosses fibres): tendons, os, peau
Type II (fibrilles fines): cartilages
Type III (fibres de réticuline entrelacées dans un réseau) : ganglions lymphatiques, rate, foie et la moelle osseuse
Type IV: lame basale
What type of collagen do we find in skin?
Type 1 collagen
What is the main site for lame elastine?
In arteries: We need a lot of elasticity.
What is one clinical implication of elastin and where do we find it?
We find it in the extracellular matrix of connective tissue proper
Clinical implication is that Synthèse d’élastine diminue avec l’âge
Where do elastic fibers come from in connective tissue proper?
From fibroblasts
What creates the substence fondementalle in connective tissue proper?
fibroblasts
What are the components of substence fondementalle in connective tissue proper?
Contient des glycosaminoglycanes (GAGs), des protéoglycanes (PGs) et du liquide interstitiel
Glycosaminoglycanes +Proteins = Proteoglycans
What are the two kinds of connective tissue proper based on fiber cell quantity?
Tissu conjonctif lâche:
Proportion ‘’équilibrée’’ de fibres et de cellules présentes
Tissu conjonctif dense:
riche en fibres
Contient moins de cellules
Where do you usually find Tissu conjonctif lâche?
Usually around epithelial cells
What are the types of connective tissue based on fiber orientation?
Tissu conjonctif dense orienté:
Tissu conjonctif dense enchevêtré
Tissu conjonctif réticulé
Where do we find tissu conjonctif dense orienté and what is the main type of collagen associated with this?
Usually in Tendons (need to remember)
Collagen Type I (mostly)
What kind of collagen fiber do we find around Tissu conjonctif réticulé?
Collagène type III ou fibres réticulaires
What cells would you expect to see in Tissu conjonctif dense orienté:?
Not many cells but the ones we see will be fibroblasts.
TRUE or FALSE, the fundemental substance will be kind of the same amount across types of connective tissue.
FALSE,
for example in Tissu conjonctif dense orienté: Substance fondamentale très réduite
Main cells in Tissu conjonctif dense enchevêtré?
Fibroblasts
