LECTURE 2 | Connective Tissue Flashcards
It encompasses the major structural constituents of the body
Connective tissue
Most connective tissues are derived from ____________, which form the multipotential mesenchyme from which bone, cartilage, tendons, ligaments, capsules, blood and hematopoietic cells, and lymphoid cells develop.
Mesoderm
A type of tissue that support, defense, transport, storage and repair.
Connective tissue
Connective tissue are mainly composed of?
- Extracellular elements
- Limited number of cells
In connective tissue:
• Mesenchymal
• Mucous
Embryonic CT
In connective tissue:
• Loose
• Reticular
• Adipose
• Dense irregular
• Dense regular
✓ Collagenous
✓ Elastic
Adult CT
Connective tissue:
• Supporting Tissues
✓ Cartilage
✓ Bone
• Blood
Specialized CT
It intricate network composed of an array of multidomain macromolecules organized in a cell/tissue-specific manner.
Extracellular Matrix
3 Subdivisions of Extracellular matrix
- Fibers
- Amorphous Ground Substance
- Extracellular Fluid
What are the 3 protein fibers?
- Elastic fiber
- Collagen fiber
- Reticular fiber
It is the most abundant of the fibers
Collagen fiber
A fiber in extracellular matrix that are inelastic, composed of a staggered array of the protein tropocollagen
Collagen fiber
How many different types of Collagen fibers are there?
25 different types
Where does the synthesis of collagen occurs?
It occurs in the Rough Endoplasmic Reticulum
What specific part of Rough Endoplasmic Reticulum does the specific proline and lysine residues are being hydroxylated, and hydroxylysine residues are being glycosylated?
Cisternae
In collagen fiber, it is the vesicles that convey the procollagen molecules to the Golgi apparatus for modification, mostly the addition of carbohydrate side chains.
Coatomer-coated transfer vesicles
Collagen:
molecules self-assemble, forming fibrils with 67nm characteristics banding.
Tropocollagen molecules
Type of collagen that is composed of procollagen rather than tropocollagen subunits, hence the absence of periodicity and fibril formation in this type of collagen.
Type IV collagen
Thin, branching, carbohydrate-coated fibers composed of type III collagen that form delicate networks around smooth muscle cells, certain epithelial cells, adipocytes, nerve fibers, and blood vessels.
Reticular fiber
Constitute the structural framework of certain organs, such as liver and the spleen
Reticular fiber
As a result of the carbohydrate coat, when stained with silver stain, the silver preferentially deposits on these fibers giving them a brown to black appearance in the light microscope.
Reticular fiber
A fiber which is a highly elastic that may stretched to about 150% of their resting length without breaking.
Elastic fibers
A fiber which is composed of amorphous protein, elastin, surrounded by a microfibrillar component consisting fibrillin.
Elastic fibers
The elasticity of elastin is due to its __________ content in that four __________ molecules, each belonging to a different elastin chain, form covalent desmosine crosslinks with one another.
Lysine
Constitutes the gel like matrix in which the fibers and cells are embedded and through which extracellular fluid diffuses.
Amorphous Ground Substance
Composed of GAG’s, proteoglycans, and glycoproteins.
Amorphous Ground Substance
GAG
Glycoaminosans (GAG’s)
Linear polymers of repeating disaccharides, one of which is always a hexosamine and the other is hexuronic acid.
Glycoaminosans (GAG’s)
Composed of protein core to which GAG’s are covalently bound.
Proteoglycans
• Localized in CT proper
• Laminin, fibronectin, chondronectin, osteonectin, entactin, and tenascin.
• Many cells possess integrins, transmembrane protein, with receptor sites.
Glycoproteins
ECF
Extra Cellular Fluid
• Tissue fluid, component of blood, carry nutrients, oxygen, signaling molecules and other blood borne materials
Extra Cellular Fluid (ECF)
A specialized cell that aids in tissue structure and repair, by depositing collagen
Fibroblast
• Synthesis of collagen, elastic, and reticular fibers, ground substance.
Fibroblast
Histiocytes
Macrophage
A cell that is derived from monocytes of bone marrow
Macrophage (Histiocytes)
A cell that migrate to the CT’s and function in ingesting foreign particular matter
Macrophage (Histiocytes)
Enhance the immunologic activities of lymphocytes
Macrophage (Histiocytes)
Major cell type during inflammation
Plasma cells
These cells are derived from a subpopulation of lymphocytes and are responsible for the synthesis and release of humoral antibodies
Plasma cells
A cell that usually observed in the vicinity of small blood vessels, although the relationship between them is not understood.
Mast cells
These cells houses, histamine (smooth muscle contractant) and heparin (anticoagulant)
Mast cells
Contractile cells, assist in the regulation of blood flow through capillaries
Pericytes
Store lipids and form adipose tissues
Fat cells
WBC’s
Leukocytes
These CT’s are limited to the embryo
Mesenchymal and Mucous CT’s
A CT’s that interspersed in a semifluid matrix of ground substance
Mesenchymal CT’s
A CT’S that are being found deep to the fetal skin and in the umbilical cord
Mucous CT’s
A type of CT’s that are being distributed widely, constitutes much of the superficial fascia and invests neuromuscular bundles.
Loose (areolar) CT’s
Composed of fat cells, reticular fibers, and rich vascular supply
Adipose tissue
Consist of coarse, almost haphazardly arranged bundles of collagen fibers interlaced with few elastic and reticular fibers.
Dense irregular CT’s
Dermis of the skin, capsules of some organs
Dense irregular CT’S
Composed either of thick, parallel arrays of collagenous fibers, as in tendons and ligaments, or of parallel bundles of elastic fibers as in the ligamentum nuchae, ligamentum flava, and suspensory ligaments of the penis.
Dense regular CT’s
5 commonly used histological stains
- Hematoxylin and Eosin
- Silver Methods
- Myelin Methods
- Alcian Blue Method
- Trichrome Method
Enumerate the function of Tissues
✓ Support
✓ Defense
✓ Transport
✓ Storage
✓ Repair
the concept that the nervous system is made up of discrete individual cells
Neuron Doctrine
A very small amino acid
Glycine
