Bone Growth joints: tissue and structure

Question 1

Definition of endochondral ossification

Answer 1

process of turning cartilage into bone

Question 2

where does the first step of bone growth (length) take place

Answer 2

The primary ossification center which is the diaphysis (shaft) of the bone

Question 3

where does the second place of bone growth (length) take place

Answer 3

the secondary ossification center which takes place in the epiphyses (bone ends) simultaneously

Question 4

what separates the diaphysis and epiphyses

Answer 4

a growth plate which fuses between the bones around puberty

Question 5

how do bones grow in length

Answer 5

Growth in length occurs in growth plate/epiphyseal plate which is made up of cartilage

Question 6

how do bones grow in width

Answer 6

osteoblast activity produces circumferential lamellae on the outside as osteoclasts mold bone shape and form the medullary cavity inside

Question 7

what are the 2 groups of soft bone tissue

Answer 7

1. cartilage:
   - hyaline (articular) cartilage
   - fibrocartilage
2. dense fiber connective tissue:
   - ligaments (bone to bone)
   - tendons (bone to muscles)
   - joint capsule (wraps around the joint to hold it in place)

Question 8

what are chondrocyte cells

Answer 8

chondrocyte cells are responsible for cartilage formation and can be found in lacuna

Question 9

explain the structure of cartilage

Answer 9

composed of specialized cells (chondrocytes) embedded in an extracellular matrix made of water, collagen fibers, proteoglycans, and sometimes elastin, and is avascular, meaning it lacks its own blood supply

Question 10

how does cartilage get nutrients

Answer 10

nutrients diffuse through matrix by joint loading (nutrients are forced into cartilage when moving)

Question 11

structure of hyaline cartilage

Answer 11

• has a high water content
• sparse collagen fibers
• molds to the surface of bones where they articulate

Question 12

function of hyaline cartilage

Answer 12

• resists compression
• allows frictionless movement between bone ends

Question 13

structure of fibrocartilage

Answer 13

contains many collagen fibers in bundles and the orientation of the fibers align with stress

Question 14

function of fibrocartilage

Answer 14

• resists compression and tension
• acts as buffer or shock absorber because it distributes force over wider area

Question 15

structure of dense fiber connective tissue

Answer 15

contains fibroblast (makes fiber), collagen fibers and some elastin fibers, that are all tightly packed together

Question 16

how does dense fiber connective tissue

Answer 16

Has little vascularity (contains some blood vessels) therefore low on nutrients

Question 17

structure of ligaments

Answer 17

contains collagen and elastin

Question 18

function of ligaments

Answer 18

restricts movement away from themselves
collagen - resist tension
elastin - allow a little stretch and recoil

Question 19

structure of tendons

Answer 19

contains collagen and some elastin (less than ligaments)

Question 20

function of ligaments

Answer 20

facilitates and controls movement as contraction of muscles are transmitted to the bone through the tendon

Question 21

what is bony congruence

Answer 21

the sum of bone surfaces that form an articulation
less congruency leads to more soft tissue being needed for support

Question 22

the 3 joint classifications

Answer 22

1. fibrous joint
2. cartilaginous joint
3. synovial joint

Question 23

what type of tissue is in fibrous joint

Answer 23

dense fiber tissue

Question 24

structure of fibrous joints

Answer 24

ligaments

Question 25

function of fibrous joints

Answer 25

limit movement and provide stability

Question 26

what type of tissue is in cartilaginous joints

Answer 26

fibrocartilage

Question 27

function of cartilaginous joints

Answer 27

allows some movement