Bone

Question 1

Examples of typical long bones

Answer 1

Humerus, radius, ulna, tibia, fibula, femur

They have two secondary epiphysis

Question 2

Examples of miniature/short long bones

Answer 2

Metacarpals, metatarsals, phalanges

They have only one epiphysis

Question 3

Examples and features of modified long bones

Answer 3

Clavicle

(They have no medullary cavity.
They transmit weight from appendicular to axial skeleton)

Question 4

Examples and features of short bones

Answer 4

Tarsals, carpals

1. Usually cuboid/scaphoid
2. Pierced by blood vessels

Question 5

Examples and features of flat bones

Answer 5

Sternum, ribs, scapula

1. Resemble shallow plates
2. Form boundaries of certain body cavities

Question 6

Examples and features of irregular bones

Answer 6

Hip bone, sphenoid, first and second cervical vertebrae

Question 7

Examples and features of pneumatic bones

Answer 7

Maxilla, sphenoid, ethmoid

They:

1. Make the skull light in weight.
2. Help in resonance of voice.
3. Act as air conditioning chambers.
4. Improve timbre of voice.

Question 8

Examples, features and functions of sesamoid bone

Answer 8

Patella, pisiform, fabella in gastrocnemius(behind and slightly above the knee), riders bone

1. No medullary cavity
2. No haversian system
3. No periosteum
4. Ossify after birth

FUNCTIONS:

1. To resist pressure
2. To minimize friction
3. To alter the direction of pull of muscle
4. To maintain local circulation
5. To protect vessels and nerves

Question 9

Examples and features of accessory bones

Applied aspects

Answer 9

Cervical ribs, lumbar ribs

• COMMON IN HYDROCEPHALIC SKULLS
• ACCESSORY BONES MAY BE MISTAKEN FOR FRACTURES

Question 10

Membrane/dermal bones

Answer 10

• ossify in membranes (intramembranous)
• derived from mesenchymal condensations

Frontal, parietal, facial bones

Question 11

Cartilaginous bones

Answer 11

• ossify in cartilage (intracartilaginous/endochondral)
• derived from replacement of performed cartilaginous models

Bones of limbs, vertebral column, thoracic cage

Question 12

Membrano- cartilaginous

Answer 12

-ossify partly in membrane and partly in cartilage

Mandible, occipital, temporal, sphenoid,

Clavicle —> sternal end endochondral
Rest is intramembranous

Question 13

Simple epiphysis define and examples

Answer 13

Ends of long bones develop from many epiphysis. These first independently with the shaft.

Femur

Question 14

Compound epiphysis definition and examples

Answer 14

The ends of bones develop from many centres which unite to form a single epiphysis. The single epiphysis fuses with the shaft.

Humerus

Question 15

Pressure epiphysis

Answer 15

• articular
• transmission of weight

Head of humerus, lower end of radius

Question 16

Traction epiphysis

Answer 16

• Non articular
• provides attachment to one or more tendons

Trochanters of femur, tubercles of humerus

Question 17

Atavistic epiphysis

Answer 17

Phylogenetically an independent bone which becomes fused to another bone

Coracoid process of scapula, os trigonum or lateral tubercle of posterior process of talus

Question 18

Aberrant epiphysis

Answer 18

Not always present

Epiphysis at the head of the first metacarpal and at the base of other metacarpals.