Histology: Connective tissue- Embryonic and Adult Connective Tissue 🔫 Flashcards
Where is connective tissue located?
It lies under the epithelia of all tissues and organs.
What does connective tissue do?
It provides both structural and metabolic support for the surrounding tissue.
What does connective tissue contain?
- rich network of blood vessels
- can contain adipocytes
What does the extra cellular matrix regulate?
- cell proliferation
- cell migration
- cell differentiation
What does epithelium tissue always have?
connective tissue beneath.
Why is epithelium tissue unable to get nutrition?
It does not have any blood vessels.
–> it cannot get nutrition, oxygen, it cannot undergo METABOLISM
What is the route of diffusion of nutrients and waste products?
nutrients: capillaries (connective tissue) –> epithelial tissue
waste products: epithelial tissue –> capillaries (connective tissue)
What are the principal functions of connective tissue?
1) provide support and form to the body and organs
2) aid in the defence and protection of the organism
3) serve as a medium of exchange of nutrients between tissues
4) store fat and thermoregulate
What is an example of connective tissue (support)?
- cartilage
- bones
What is an example of connective tissue (defense and protection)?
white blood cells, fight against pathogens, bacteria, paracytes, viruses etc.
What is an example of connective tissue (medium of exchange of nutrients)?
red blood cells (erythrocytes)
What is an example of connective tissue (fat and thermoregulation)?
loose and dense connective tissue ??
What is the role of adipose tissue? What is its non-prefessional name
adipose tissue=fat tissue
storage of energy
What is connective tissue composed of?
cells and an extracellular matrix (ECM) (fibers and ground tissue).
What is the “ECM”?
the ExtraCellular Matrix
What does the extracellular matrix consist of?
- PROTEIN FIBERS (collagen, elastic and reticular fibers)
- amorphorus component containing specialized molecules (proteoglycans, multiadhesive glycoproteins, and glycosaminoglycans) that constitute to the GROUND SUBSTANCE.
What are the three principal types of connective tissue fibers?
1) collagen fibers
2) reticular fibers
3) elastic fibers
What are collagen fibers?
- flexible
- high tensile strength
- formed from collagen fibrils
- formation: fibroblasts and ECM
- most abundant type of fibers
What are collagen fibers formed from?
collagen fibrils
What does collagen fiber formation involve?
events that occur:
1) within the fibroblasts- production of procollagen molecules
2) outside the ECM- polymerization of collagen molecules into fibril, which are assembled into larger collagen fibers.
Where does the production of procollagen molecules occur?
fibroblasts
Where does the polymerization of collagen molecules into fibril occur?
outside the extracellular matrix.
What type of fibers is most abundant in connective tissue?
collagen fibers
What type of fibers are most flexible?
elastic fibers
How are elastic fibers produced?
Elastic fibers are produced by fibroblasts and smooth muscle cells.
What do elastic fibers allow epithelial tissues to do?
respond to stretch and distension.
distention- act of swelling
What are elastic fibers composed of?
a CENTRAL CORE OF ELASTIN associated with a network of FIBRILLIN MICROFIBRILS (made up of fibrillin and emilin)
What are fibrillin microfibers composed of?
fibrillin and emilin
Q. What type of fibers does a human ear contain?
a lot of elastic fibers, and a few collagen fibers
(it returns to its shape when moved)