Cartilage

interstitial growth

Chondrocytes divide and secrete new matrix, expanding cartilage from within the process that form new cartilage within an existing cartilage Mass. very active during endochondral ossification. cell divide by mitosis, isogenous cell group appear. cell produce ECM cartilage Mass increase

endochondral ossification

process in which bone forms by replacing hyaline cartilage

Cartilage types

hyaline, elastic, fibrocartilage

cartilage growth

interstitial and appositional

fibrocartilage function

supports, protects, absorbs shock

cartilage

A connective tissue that is more flexible than bone and that protects the ends of bones and keeps them from rubbing together. cartilage is a semi rigid but flexible avascular connective tissue found at various sites within the body. with a pliable structure composed primarily of water, this tissue type is also extremely tough. cartilage is found to have the human body areas such as the joint, nose, airway, intervertebral discs of the spine, and the ear.

cartilage function

cartilage function more than structure, and does a different functions in the life cycle. in the embryo its provide support and is the precursor to the Bone. embryonic cartilage either remains as a cartilage or provide a substructure for endochondral ossification. cartilage allow facial movement as well providing I lightweight supportive structure in the external ear, and the tip and septum of the nose. in other regions it's act as a shock absorber, cushion areas where bones meet bones and preventing friction and damage, also a joint will not be able to band without the flexibility of cartilage. a combination of role is seen in the airways, where cartilage rings around the trachea prevent collapse and damage, cartilage at the end of the ribs allow the ribcage to swing upward and outward during inspiration. and cartilage play a role in bone repair where, as in the embryo, it provides a temple for ossification, this time to broken sections of bone.

cartilage structure

cartilage is a connective tissue consists of dense matrix of collagen fibers and elastic fibers embedded in a rubbery ground substance (hyaluronic acid, proteoglycans and small amount of several glycoproteins). The matrix is produced by cells called chondroblast, which become embedded in the matrix as chondrocytes. chondrocytes are the mature cartilage cells. they occur, either singly or in a groups, within a space called lacunae in The matrix. the surface of the cartilage in the body is surrounded by a membrane of dense irregular connective tissue called perichondrium. it's important to remember because unlike other connective tissue, cartilage contains no blood vessels or nerves except in the perichondrium. cartilage divided into three types which are hyaline cartilage, fibrocartilage, and elastic cartilage.

Fibrocartilage cells

chondrocytes are smaller then hyaline and elastic cartilage, surrounded by small amount of matrix and usually oriented in parallel row.

structure of the hyaline cartilage

consist of type 2 collagen. consists of the molecule chondroitin sulfate, which helps it to resist being compressed. however is the weakest of the three types because it's collagen fibers are very fine. does not have nerves or blood vessels. instead, it has simple structure which is mainly made up of group of chondrocytes embedded in an intercellular matrix. have one or two nuclei. has perichondrium two layers 1 will be fibrous layer will be the outer layer contain collagen type 1 blood vessels and less fibroblasts and inner layer will be chondrogenic consists of chondroblast which synthesize and secrete component of extracellular matrix. chondrocyte arranged in groups surrounded by capsules isogenous group

elastic cartilage function

elastic cartilage function is to change cartilage shape in response to tension, compression, and bending before returning to end at rest state, and to provide a strong but flexible structure. for example in the outer ear if it wasn't bone that we will not be able to sleep on that and that it will go back to the same position, at the epiglottis and larynx when l pass through the larynx during inspiration and expiration. should a person swallow, the epiglottis is pulled back and cover the opening into the larynx which lies in front of the opening into the esophagus. this action prevent saliva and food from entering the airway, elastic cartilage in the epiglottis is important as it maintains the form of the valve like and always spring back into the rest position allowing the body do the most important process breathing. in the eustachian tube it's important because when we are nose blowing or yawning, as during these actions the eustachian tubes open and allow air to enter into the middle ear, reducing the difference between middle ear and atmospheric pressure.

elastic cartilage

elastic cartilage one of the types of cartilage found in the human body primarily in the external ear (auricle or pinna) and epiglottis and eustachian tub. form of connective tissue, elastic cartilage is also recognized by its ability to snap back into an original form or resting form due to the addition of elastin fibers of The extracellular matrix. this fibres type distinguish elastic cartilage from all other forms. it is usually recognizable by its yellow color. a special stains must be used to show otherwise invincible elastic fibre that give this particular cartilage types its name. (stain VVG/EL). has a single or multiple chondrocytes house within spaces called lacunae. The extracellular matrix of elastic cartilage contains higher level of type 2 collagen. chondrocytes and extracellular matrix are contained within an outer layer known as perichondrium outer layer contain fibroblast and inner layer contains chondroblast.

Fibrocartilage

found where tendons and ligaments meet bone, menisci, sternoclavicular joint and annulus fibrosus. the fibrocartilage is very strong it is rainforest with collagen fiber bundle that run parallel to each other, allowing a low level of stretch. because of the abundance of collagen fiber, fibrocartilage is white in appearance, no perichondrium composed of type 2 and type 1 collagen fibers. fibrocartilage blends with the surrounding fibrous tissue, therefore does not have perichondrium, synovial fluid is the source the supplies nutrition due to the absence of perichondrium.

appositional growth

growth in width increase bone thick that process that forms new cartilage at the surface of an existing cartilage bone growth during embryonic period, regeneration of mature cartilage. ✓cells of chondrogenic layer differentiate into chondroblast. ✓chondroblasts produce ECM the new matrix increases the cartilage Mass. ✓new layers of cells and ECM are added to the surface of the cartilage

hyaline cartilage definition

hyaline cartilage is the type of connective tissue found in areas such as the nose, the ear, and trachea of the human body. the world hyaline means glass like in Greek, hyaline cartilage is glossy, grayish white tissue with a uniform appearance. it is the most abundant type of cartilage in the body.

fibrocartilage location

intervertebral discs(connecting fibrocartilage present in limited motion joint), pubic symphysis, discs of knee joint (intra-articular fibrocartilage pleasant where joints are flexion and extension associated with gliding) stratiform fibrocartilage - thin layer over the bone where the tendons may glide tibialis posterior. circumferential fibrocartilage for example glenoid and acetabular labrum present in the form of a ring without a center to protect the joint margins and improve the bony fit.

intramembranous ossification

process by which bone forms directly from mesenchymal tissue

function of hyaline cartilage

supports and reinforces. hyaline cartilage provide support and flexibility to different parts of the body it is found in structure like the nose, ears, and area where the end of the ribs attach to the sternum and in part of the respiratory system like the trachea and larynx, where it helps give these parts their form but also give them some flexibility. important to say that in synovial joint the cartilage will be named articular cartilage. is hyaline cartilage that is found on the articular surface of the bone, which is where bones meet and formes joint.

elastic cartilage outer ear

the outer ear is relatively unprotected and stick out from the skull.