Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

CARTILAGE.pdf, Summaries of Histology

Appearance : characteristics between dense connective tissue and cartilage. Composition : 1. chondrocytes – small, spindle-shaped, similar to fibroblasts.

Typology: Summaries

2021/2022

Uploaded on 09/12/2022

andreasphd
andreasphd 🇬🇧

4.7

(28)

288 documents

1 / 7

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
Department of Histology and Embryology, P.J. Šafárik University, Medical
Faculty, Košice
Cartilage : Sylabus for foreign students
Author: RNDr. Marianna Danková, PhD.
Revised by: prof. MUDr. Eva Mechírová, CSc.
CARTILAGE
Characteristic :
- supporting connective tissue
- tolerates mechanical stress without permanent distortion (firm consistency
of extracellular matrix)
- resilient
- without blood vessels (avascular)
Function : - supports soft tissues
- shock absorbing and sliding area for joints (smooth surface),
- essential for the development and growth of long bones
Composition :
A: CELLS : 1. chondrocytes - synthesize and secrete extracellular matrix
- located in matrix cavities lacunae
EM : organelles typical of protein secretory cells (rER, GA)
2. chondroblasts synthesize and secrete extracellular matrix
3. chondroclasts belong to mononuclear phagocyte system
involved in destruction of the cartilage
B: EXTRACELLULAR MATRIX :
a) amorphous ground substance
1. glycosaminoglycans hyaluronic acid, chondroitinsulfate, keratansulfate
2. proteoglycans form proteoglycan aggregates that interact
with collagen and bind the water
3. structural glycoproteins - chondronectin
b) fibrils 1. collagen II fibres are not formed, fibrils with diameter 20nm
2. collagen I form fibers, in fibrocartilage
3. elastic fibers in elastic cartilage
pf3
pf4
pf5

Partial preview of the text

Download CARTILAGE.pdf and more Summaries Histology in PDF only on Docsity!

Department of Histology and Embryology, P.J. Šafárik University, Medical Faculty , Košice Cartilage : Sylabus for foreign students Author: RNDr. Marianna Danková, PhD. Revised by: prof. MUDr. Eva Mechírová, CSc.

CARTILAGE

Characteristic :

- supporting connective tissue

  • tolerates mechanical stress without permanent distortion (firm consistency of extracellular matrix)
  • resilient
  • without blood vessels (avascular)

Function : - supports soft tissues

  • shock absorbing and sliding area for joints (smooth surface),
  • essential for the development and growth of long bones

Composition :

A: CELLS : 1. chondrocytes - synthesize and secrete extracellular matrix

  • located in matrix cavities – lacunae EM : organelles typical of protein secretory cells (rER, GA)
  1. chondroblasts – synthesize and secrete extracellular matrix
  2. chondroclasts – belong to mononuclear phagocyte system involved in destruction of the cartilage

B: EXTRACELLULAR MATRIX :

a) amorphous ground substance

  1. glycosaminoglycans – hyaluronic acid, chondroitinsulfate, keratansulfate
  2. proteoglycans – form proteoglycan aggregates that interact with collagen and bind the water
  3. structural glycoproteins - chondronectin

b) fibrils – 1. collagen II – fibres are not formed, fibrils with diameter 20nm

  1. collagen I – form fibers, in fibrocartilage
  2. elastic fibers – in elastic cartilage

 - the cartilage matrix immediately surrounding each chondrocyte is rich in glycosaminoglycans and poor in collagen – territorial or capsular matrix (intense basophilia, metachromasia)  - matrix located between the capsules – interrteritorial matrix

1- collagen fibrils (collagen type II ) 2 – hyaluronic acid 3 – link protein 4 – chondroitinsulfate - glycosaminoglycan 5 – core protein 6 - proteoglycan

2. Interstitial growth – mitotic division of preexisting chondrocytes 1.during early phases of cartilage formation

  1. within the epiphyseal plates in long bones (increasing the length)
  2. within articular cartilage 1. Oval isogenous groups 2. Columns of isogenous groups during ossification

Regeneration by appositional growth from perichondrium; the chondroblasts from perichondrium invade the damaged area and generate new cartilage in extensively damaged areas the cartilage is replaced by dense connective tissue

Types of cartilage:

  1. Hyaline cartilage
  2. Elastic cartilage
  3. Fibrocartilage

1. HYALINE CARTILAGE

Incidence : articular surfaces, wall of large respiratory passages – larynx, trachea, bronchi, epiphyseal plate, ventral ends of ribs, embryonic temporary skeleton

Appearance : bluish-white, translucent

Composition :

1. chondrocytes

  • spherical in shape, at the periphery elliptic
  • appear in groups - up to 8 cells originating by mitotic division of a single chondrocyte – isogenous group
  • housed in matrix cavities- lacunae (in living tissue fill the lacunae, shrinking during preparation) 2. extracellular matrix - (glassy )- cells are surrounded by basophilic matrix – territorial (capsular) matrix (rich in acidic glycosaminoglycans) and interterritorial matrix – smooth, paler, less basophilic ( collagen II - does not form fibres, fibrilles interact with proteoglycan aggregates, are not visible by LM because their refractive index is similar to that of ground substance and are masked by the glycosaminoglycans; hence the matrix appears homogeneus and smooth)

3. FIBROCARTILAGE

Incidence : intervertebral discs, symphysis pubis

INTERVERTEBRAL DISC

  • shock absorber
  • situated between articular surfaces of neighbouring vertebrae
  • have 2 components:
  1. Annulus fibrosus – fibrocartilage, concentric layers
  2. Nucleus pulposus – in the centre; ground substance + few cells, col. II.

Appearance : characteristics between dense connective tissue and cartilage

Composition :

1. chondrocytes – small, spindle-shaped, similar to fibroblasts arranged singly or in long rows 2. extracellular matrix – great number of collagen I fibers – acidophilic, amorphous matrix less abundant Perichondrium is not identifiable.