Lesson 6 Flashcards
They consists of heterogeneous populations of cells that are separated from each other by a substantial amount of intercellular substance mostly secreted by the constituent cells.
Connective Tissue
These two intercellular substance both comprise the connective tissue matrix.
both fibrous and amorphous
It holds, binds, and supports other tissues of the body.
connective tissue
What is the origin of all connective tissues?
They are derived from the mesoderm.
What are the stem cells of connective tissue?
Mesenchymal cells.
What separates connective tissues from non-connective tissues?
The basal lamina.
What are the four criteria for classifying connective tissue?
- Predominant cell type or types.
- Type of fibrous components in the matrix.
- Number of fibers in a unit area of the matrix.
- Orderliness of the matrix components.
What are the two main components of the intercellular material in connective tissue?
Fibers and ground substance.
What are the three types of fibers in connective tissue?
- Collagenous.
- Reticular.
- Elastic.
What is the nature of ground substance in connective tissue?
Amorphous.
What are the two categories of cells in connective tissue?
Resident cells and transient/migrant cells.
What are examples of resident cells in connective tissue?
- Mesenchymal cells.
- Reticular cells.
- Fibroblast (fibrocytes).
- Macrophages.
- Pericytes.
- Fat cells.
- Mast cells.
- Foreign body giant cells.
What are examples of transient/migrant cells in connective tissue?
- Plasma cells.
- Pigment cells.
- Lymphocytes.
- Monocytes.
- Neutrophils.
- Eosinophils.
- Basophils.
What is another constituent of connective tissue besides intercellular material and cells?
Tissue fluid
What are the two main components of the intercellular material in connective tissue?
Fibers and ground substance
What is the nature of the fibers in connective tissue?
Glycoprotein in nature
What is the staining property of collagenous fibers with H&E stain?
Pink-staining
Which cells produce collagenous fibers?
Fibroblasts
What produces the fibers in connective tissue?
Connective tissue cells.
What is the most numerous type of fiber in connective tissue?
Collagenous fibers.
How many different types of collagen are currently known?
15 types (e.g., Type I, II, III, IV).
What is the structural hierarchy of collagenous fibers? (How it is formed)
Tropocollagen molecules → Microfibrils → Fibrils → Fibers.
Which techniques are used to stain reticular fibers effectively?
Silver (argyrophilic) and PAS (Periodic Acid-Schiff) techniques.
What type of collagen forms reticular fibers?
Type III collagen.
What is the arrangement of reticular fibers?
They are arranged in a network.
What is the diameter of reticular fibers?
0.5–2.0 µm.
What cells produce elastic fibers?
Fibroblasts and smooth muscle cells of blood vessels.
What protein composes the core of elastic fibers?
Elastin.
What is the appearance of elastic fibers in a stretched state?
Long, thin, straight, and branched fibers.
What molecular bonds are responsible for the elasticity of elastin?
Desmosine cross-links.
What surrounds the core of elastin in elastic fibers?
A sheath of microfibrils composed of glycoprotein fibrillin.
What is the nature of ground substance in connective tissue?
Amorphous material in a viscous gel form.
They are meant to bind great quantities of water and facilitate the movement of metabolites and waste products.
ground substance
What are the three main components of ground substance?
Glycosaminoglycans, proteoglycans, and glycoproteins.
What is the structural nature of glycosaminoglycans?
Negatively charged, long rod-like chains of repeating disaccharides.
Negatively charged, long rod-like chains of repeating disaccharides.
glycosaminoglycans
Bind large quantities of water and give tissue greater resistance to compression forces.
glycosaminoglycans
What are the sulfated glycosaminoglycans?
- Keratin sulfate,
- heparin sulfate,
- heparin,
- chondroitin 4-sulfate,
- chondroitin 6-sulfate,
- and dermatan sulfate.
What is the non-sulfated glycosaminoglycan?
Hyaluronic acid.
A protein core with glycosaminoglycans covalently bonded to it.
Proteoglycans
What is an example of a proteoglycan?
Aggrecan.
Produces the gel state of the extracellular matrix and serves as a barrier to the diffusion of aqueous substances.
aggrecan
is a protein that’s part of basement membranes throughout the body. It’s also known as heparan sulfate proteoglycan 2 (HSPG2).
Perlecan
Facilitate the attachment of cells to the extracellular matrix.
cell adhesive glycoproteins
What are the major types of adhesive glycoproteins and their locations?
- Fibronectin: Throughout the extracellular matrix.
- Laminin: Basal laminae.
- Entactin and Tenascin: Embryonic tissues.
- Chondronectin:Cartilage.
- Osteonectin: Bone.
They possess binding sites for components of extracellular matrix as well as for integrin molecules of the cell membrane thus facilitate the attachment of cells to the extracellular matrix
Glycoproteins
