Connective Tissue And Cartilage

Question 1

This is the most varied and abundant tissue

Answer 1

Skeletal connective tissue

Question 2

Connective tissue definition

Answer 2

Complex of cells and ECM that provides supporting and connecting framework for all other tissues of the body

Question 3

ECM form internal …… of vertebrate body
ECM composition dictates ……..

Answer 3

ECM forms internal scaffold/architecture of vertebrate

ECM composition dictates mechanical properties

Question 4

2 components of ECM scaffold

Answer 4

Fibers and ground substance

Question 5

Components of fibers

Answer 5

Collagenous or fibrilar (30 types of collagens)
Reticular (non-fibril forming collagens)
Elastic (elastin)

Tensile strength support

Question 6

Components of ground substance

Answer 6

Glycosaminoglycans, proteoglycans, glycoproteins

Question 7

Structural glycoproteins

Answer 7

Fibronectin, laminin, vitronectin, tenascin, thrombospondin, entactin

Question 8

Cartilage and bone are specialized …..

Answer 8

Connective tissues

They have a much larger ECM to cell ratio than other CTs

Question 9

The ECM is secreted by

Answer 9

Chondrocytes

Question 10

Components of individual collagen molecule

Answer 10

Type II collagen
Trimeric (3 polypeptide chains)
Rigid, rope-like
Positively charged (basic amino acids)

Question 11

Collagen fibril composition

Answer 11

Composed of individual, quarter-staggered collagen molecules
Eosinophilic

Question 12

Eosin is negatively charged and selectively binds to ……

Answer 12

Positively charged collagen molecules

Question 13

What is the Supramolecular aggregate of sulfated proteoglycans

Answer 13

Ground substance of the cartilage ECM

Question 14

3 GAGs in the ground substance of ECM

Answer 14

Chondroitin sulfate and keratan sulfate and hyaluronic acid backbone

Question 15

Describe GAGs charge and its effect

Answer 15

GAGs are negatively charged due to the sulfate group and repeal each other, so they are spread out throughout the substance of the ECM

Question 16

What does the negative charge of GAGs do as far as staining and hydration

Answer 16

GAGs are hydrophilic, basophilic, ANS metachromatic

Question 17

Explain metachromatic GAGs

Answer 17

Because of the negative charge of GAGs, when stained, the collagen changes the color of the stain

Question 18

Function of type 2 collagen in cartilage ECM

Answer 18

Provides rigid structural support and tensile strength

Question 19

Function of PG and GAG aggregates in cartilage ECM

Answer 19

Hydration

Question 20

Hydrated sponge concept

Answer 20

Cartilage can withstand great compressive forces due to stabilizing collagen matrix and ability of PG aggregates to release water and allow the matrix to compress/expand

Question 21

When cartilage is compressed, PG/GAGs are

Answer 21

Stressed because they are closer together

Question 22

Molecular sieve concept

Answer 22

Nutrient and gas exchange occurs via ECM and perichondrial blood vessels and ECM selectively sequesters various molecules

Question 23

Is hyaline cartilage mineralized

Answer 23

No

Question 24

4 steps of chondrogenesis

Answer 24

Mesenchymal condensation
Chondroblasts
Chondrocytes
isogenic groups

Question 25

Mesenchymal condensation

Answer 25

First step of chondrogenesis Central cells become chondroblasts Peripheral cells become two-layered perichondrium

Question 26

Chondroblasts in chondrogenesis

Answer 26

Divide and secrete ECM Distance between neighboring cells increase

Question 27

Chondrocytes in chondrogenesis

Answer 27

Cells surrounded entirely by ECM

Question 28

Isogenic groups in chondrogenesis

Answer 28

As cells divide, daughter cells remain in close proximity, forming chondrocyte clusters

Question 29

Space/nest occupied by chondrocytes

Answer 29

Lacunae

Question 30

Mesenchyme definition

Answer 30

Undifferentiated cells that eventually make up connective tissue

Question 31

The inner perichondrial layer is made of

Answer 31

Mesenchymal cells

Question 32

This matrix is eosinophilic

Answer 32

Interterritorial matrix

Question 33

2 mechanisms of cartilage growth

Answer 33

Apositional and interstitial

Question 34

Apositional cartilage growth

Answer 34

Involves differentiation of chondroprogenitors (mesenchyme) and Chondroblasts on the inner surface of the perichondrium into chondrocytes

Question 35

Interstitial cartilage growth

Answer 35

Involves division of pre-existing chondrocytes within a cartilage matrix, giving rise to Isogenous groups

Question 36

3 cartilage types

Answer 36

Hyaline, elastic, fibrocartilage

Question 37

Hyaline cartilage: functions

Answer 37

Function: structural support, rapid growth, ability to withstand compression; serves as a temporary skeleton during embryogenesis

Question 38

What cartilage is in fetal skeletons

Answer 38

Hyaline cartilage

Question 39

What type of cartilage is found in adults in respiratory passages like the laryngeal, trachea and bronchial cartilage

Answer 39

Hyaline cartilage

Question 40

What type of cartilage is found in adults in the cushioning of joints such as articular and costal cartilages

Answer 40

Hyaline cartilage

Question 41

What type of collagen is hyaline cartilage

Answer 41

Type 2

Question 42

What is elastic cartilage composed of

Answer 42

Type two collagen and elastin

Question 43

Functions of elastic cartilage

Answer 43

Flexible support, ability to withstand deformation

Question 44

Locations of elastic cartilage

Answer 44

External ear, auditory tubes, epiglottis, larynx cartilages

Question 45

What is fibrocartilage composed of

Answer 45

Type 1 and type 2 collagen HYBRID

Question 46

Functions of fibrocartilage

Answer 46

Attachment to bone, restricted mobility under great mechanical stress

Question 47

Locations of fibrocartilage

Answer 47

Annulus fibrosus of intervertebral disk, pubic symphysis, bone-ligament junctions

Question 48

Fibrocartilage is always found in conjunction with

Answer 48

Dense connective tissue

Question 49

Hyaline cartilage serves as a temporary skeleton during embryogenesis and then is gradually replaces by trabecular bone and marrow in what process?

Answer 49

Endochondral ossification

Question 50

Endochondral ossification defines all skeletal elements where …… will occur

Answer 50

Hematopoiesis