Connective Tissue Flashcards
1
Q
indigenous connective tissue cells
A
- arise within the CT
- mesenchymal stem cells
- fibroblasts
- adipocytes
- osteogenic cells and their derivatives
- chondrogenic cells and their derivatives
2
Q
mesenchymal cells
- what can they diff into? 5
- appearance
A
- multipotent stem cells that can differentiate into: myocytes, adipocytes, chondrocytes, osteoblasts, neurons
- cytoplasm extends out into long processes
3
Q
fibroblasts
- found in
- synthesize what
- staining/appearance
- differentiation
A
- most common cell in connective tissue
- synthesize most ECM components
- cytoplasm and ECm stain similarly - so you usually just see nuclei
- have capacity to differentiate into myofibroblasts (both in normal and wound healing conditions)
4
Q
white adipocytes
A
-unilocular white spot in each cell, nucleus pushed to the side
5
Q
brown adipocyte
A
-multilocular white spots in cell with distinct nucleus
6
Q
immigrant cells
A
- macrophages (derived from monocytes)
- mast cells
- lyphocytes
- plasma cells (from B lymphocytes)
7
Q
macrophage
- come from
- function
- appearance
A
- derived from blood monocytes that have wandered into connective tissue
- scavenge debris and function in both the innate and adaptive immune system and in inflammation
- irregular nucleus, large cytoplasm with phagosomes
8
Q
mast cells
- come from
- appearance
- characteristic of granules
- granule contents
- what can happen in allergic reaction
A
- derived from bone marrow precursors
- central nucleus with cytoplasm packed with granules
- granules exhibit metachromasia
- granules contain heparin (anticoagulant) and histmaine (vasodilator)
- in severe allergic reactions, body wide degranulation can lead to anaphylaxis
9
Q
lymphocytes
- reticulate
- subsets of
- appearance
- when found in connective tissues they are called
A
- reticulate (blood to CT to blood)
- subsets of B and T cells
- small dark nuclei with little cytoplasm
- “wandering lymphocyte”
10
Q
plasma cells
- what are they
- function
- found in what CT specifically
- appearance
A
- differentiated B lymphocytes
- synthesize antibodies of same specificity of parent B cells
- found in loose CT’s
- clock face heterochromatin pattern
- eccentric nucleus
- prominent, perinuclear golgi apparatus
- abundant RER
11
Q
Collagen
- made up of
- cross link between
A
-composed of fibrils
cross linked between
-hydroxylysine and hydroxyproline
12
Q
Scurvy
- cause
- symptoms
A
- a vitamin C deficiency
- this is a cofactor for the enzymes which crosslink fibrils of collagen
- causes problems with the periodontal ligament, poor wound healing, and bruising
13
Q
fibrillar collagen types to remember and their location
A
1-ubiquitous
2-cartilage
3-many organs
14
Q
type 1 collagen diseases
A
- ehlers danlos
- keloids - accumulation
15
Q
type 2 collagen
-where is it found and when
A
- abundant in hyaline cartilage
- found in many organs during development
- in the adult eye and ear
16
Q
type 3 collagen
- appearance
- found where specifically
- part of what epithelial specialization
A
- highly branched
- requires special stains to visualize
- found in many lymph organs, liver, and reticular dermis (skin)
- part of the reticular lamina
17
Q
non-fibrillar collagens
A
- represent the majority of known collagens
- basement membrane (collagen 4)
- associate with fibril collagens
- most require special techniques such as IHC to localize
18
Q
elastic fibers
- synthesis
- cross linking done by
A
- synthesis: deposition of fibrillar scaffold, addition of (tropo)elastin
- cross linking achieved with lysyl oxidase
19
Q
marfans syndrome
- cause
- symptoms
- TGF-b
A
- fibrillin-1 is mutated
- leads to aneurisms, scoliosis, hyper extensible joints
- fibrillin sequesters TGF-b and regulates its bioavailability
- excess TGF-b might lead to much of the marinas phenotype
20
Q
Cutis laxa
A
- mutation in elastin lead to skin that is loose, wrinkled and lacking elasticity
- in severe cases, internal organs could be affected
21
Q
ground substances
A
- proteoglycans
- glycosaminoglycans
- glycoproteins
22
Q
characteristics of ground substances
A
- highly charged conferring their hygroscopic nature
- charge confers compressive resistance (articulate cartilage)
- limited protein components (stains poorly)
- permits nutrient/gas exchange
23
Q
connective tissue types
A
- dense regular
- dense irregular
- loose (areolar)
- elastic
- adipose
- reticular
- cartilage
- bone
24
Q
dense regular CT
- definition
- appearence
A
- collagenouse tissue with densely packed fibers in parallel
- eosinophilic
- provides tensil strength to tendons and ligament
- fibroblasts spaced throughout
25
Q
Dense irregular CT
A
- collagen is not laid down in parallel orientation, it is wavy and moving in and out of the plane of view
- fibroblasts throughout which are oriented in many different ways
26
Q
loose connective tissue
A
- appears to have large empty spaces, however this is where the ground tissue resides which is very hydrated
- collagen fibers, elastic fibers, fibroblasts, mast cells, vessels
27
Q
elastic tissue
-found where
A
-found in artery (lamella) wall and dermis (branched)
28
Q
reticular tissue
A
- branched type 3 collagen
- supports channels in live, lymph nodes and spleen
- usually require special stains to visualize
