Intro to the skeletal system

Question 1

Identify the Skeletal system

Answer 1

components: bones, cartilages, joints
regions: axial, appendicular
functions: support, protection, levers, joints, movement, blood cell protection

Question 2

Identify the location and function of cartilage in the skeletal system

Answer 2

Hyaline cartilage: costal cartilages, articular cartilage, infant model for developing bones
Fibrocartilage: articular cartilage, menisci (knee)/articular discs

Question 3

Describe the two types of cartilage growth

Answer 3

1. Interstitial growth - from within the cartilage

2. Appositional growth - along with cartilage periphery (on surface)

Question 4

Describe the process of Interstitial growth

Answer 4

1. Mitosis of chondrocytes in lacunae
2. Forms two chondroblasts per lacunae
3. Each synthesise and secrete new matrix
4. New matrix separates the cells, now called chondrocytes
   Results in: larger piece of cartilage, newest cartilage on the inside

Question 5

Describe the process of Appositional growth

Answer 5

1. Mitosis of stem cells in perichondrium
2. Adds chondroblasts to periphery
3. Produce matrix, become chondrocytes in lacunae
   Results in: larger pieces of cartilage, newest cartilage on outside edges

Question 6

Identify and briefly describe the 4 types of bones

Answer 6

1. Long: greater length than width, presence of a shaft
2. Short: length and width similar, includes sesamoid bones in tendons
3. Flat: flat, parallel surfaces
4. Irregular: complex shapes

Question 7

Describe the 2 methods of ossification

Answer 7

Ossification is the formation of bone tissue

1. Intramembranous = forms within a membrane (mandible, part of the clavicle and most bones of the craniofacial complex)
2. Endochondral = forms from a hyaline cartilage model

Question 8

Describe how bones grow

Answer 8

• a long bone grows in length dye to interstitial growth of hyaline cartilage in epiphyseal plate
• growth in a bones diameter occurs as a result of appositional growth and occurs in the periosteum
• interstitial growth occurs at the epiphyseal plate
• appositional growth occurs between the circumferential lamellae and the periosteum increasing bone width