Cartilage

Question 1

What constitute the supportive CT? and what is the function?

Answer 1

Function: support soft tissues and body weight. 1. cartilage (shock absorption and protection) 2. Bone (weight support)

Question 2

What is the cartilage matrix composed of?

Answer 2

1. proteoglycans (derived from chondroitin sulfate) 2. ground substance proteins

Question 3

What are chondrocytes and what do they produce?

Answer 3

they are cartilage cells and produce antiangiogenesis factor.

Question 4

What are the two layers of the perichondrium?

Answer 4

1. outer –> fibrous (strength) 2. inner–> cellular (growth and maintenance)

Question 5

What is the fetal skeleton composed of?

Answer 5

hyaline cartilage.

Question 6

What type of collagen fiber will you find in the matrix?

Answer 6

Type II

Question 7

what type of CT is cartilage?

Answer 7

dense CT

Question 8

From where do additional chondrocytes arise?

Answer 8

fibroblast-like-stem cells in the perichondrium

Question 9

What substance do chondrocytes secrete?

Answer 9

type II collagen fiber and ground substance

Question 10

Where is collagen synthesized

Answer 10

RER

Question 11

What constitute the ground substance?

Answer 11

GAGs Proteoglycans proteoglycans aggregates glycoproteins tissue fluid

Question 12

What are GAGs composed of?

Answer 12

chondroitin sulfate and hyaluronan.

Question 13

What is a lacuna?

Answer 13

potential space occupied by a chondrocyte. This is only visible after cell’s death or ager shrinkage during tissue processing.

Question 14

What is the difference between capsular(territorial) an intracapsular (inter territorial) matrix?

Answer 14

The capsular (territorial) matrix is the matrix immediately surrounding the chondrocyte. This is more basophilic (acidic) and PAS-positive than inter capsular matrix (higher sulfated GAG concentration and lower collagen concentration. )

Question 15

Where is cartilage derived from?

Answer 15

embryonic messenchyme.

Question 16

What is mesenchymal condensation?

Answer 16

this is a process that happens when mesenchymal cells retract their cytoplasmic extensions and become round shape, becoming more tightly packed. This stimulated the commitment to cartilage differentiation.

Question 17

When does a chondroblast becomes a chondrocyte?

Answer 17

when is surrounded by cartilage matrix

Question 18

What are the two process of cartilage growth? and what do they involve?

Answer 18

They both involve mitosis and deposition of additional matrix. 1. Interstitial growth: division of existing chondrocytes and gives rise to isogenous groups. Division within the lacuna. As the daughter cells secret matrix they move apart. **Important in fetal skeleton and continues in the epiphyseal plates and articular cartilages 2. Appositional growth: involves differentiation of chondrocytes by chondroblast and stem cells on perichondrium inner surface. **It is responsible for increases in the growth of the cartilage masses.

Question 19

Matrix synthesis is affected by what factors?

Answer 19

enhanced by growth hormones, thyroxine, and testosterone. inhibited by estradiol and excess cortisone.

Question 20

What is the function and location of hyaline cartilage?

Answer 20

Function: Reduces friction in joints. Its ability to grow rapidly while maintaining its rigidity makes hyaline cartilage an ideal fetal skeletal tissue. Location: The costal (rib) cartilages, most of the laryngeal cartilages, the cartilaginous rings supporting the trachea, and the irregular cartilage plates in the walls of the bronchi are hyaline cartilage.

Question 21

How is elastic carriage different from elastic cartilage?

Answer 21

it contains collagen II and elastic fibers.

Question 22

how does elastic cartilage looks?

Answer 22

It has perichondrium, chondrocytes occur in isogenous groups and is stained darker than hyaline cartilage.

Question 23

Where does elastic fibers develop from?

Answer 23

Elastic cartilage develops from a primitive connective tissue containing wavy fibrillin bundles. Fibroblasts subsequently secrete elastin, and the fibrillin bundles are transformed into branching elastic fibers.

Question 24

Where is elastic cartilage located?

Answer 24

elastic cartilage occurs in the external ear, the external auditory canals and auditory tubes, the epiglottis, and the corniculate and cuneiform cartilages of the larynx.

Question 25

What type of fibers collagen fibers occur in fibrocartilage?

Answer 25

collagen type I. Always associated with dense CT.

Question 26

Where is fibrocartilage located?

Answer 26

where strong mechanical stresses occur. intervertebral disks, the symphysis pubis, and some bone–ligament junctions.