Unit 1 - Anatomy - Skeletal System

Question 1

How many bones does the body have? What percent of body weight do bones account for?

Answer 1

Humans start with 300 bones which later fuse, leaving us with 206 bones. Bones account for 14% of total body weight.

Question 2

What are the longest and smallest bones?

Answer 2

The longest is the femur, in the thigh, the shortest is the stirrup, in the ear.

Question 3

What is the difference between male and female skeletal structures?

Answer 3

Males have longer arm and leg bones, females have wider pelvises to support the birthing process.

Question 4

What are bones mostly made of?

Answer 4

Bones are mainly made of calcium, causing them to be hard and durable.

Question 5

What can cause the weakening of bones? Who is this a concern with?

Answer 5

Lack of calcium. This is a concern with children if the calcification process is still incomplete. Concern with the elderly as they suffer from loss of calcium.

Question 6

5 major functions of the skeletal system?

Answer 6

Structural Support - rigid supporting framework. Protection - skull for brain, ribs for heart and lungs. Movement - lever system on which attached muscles work. Growth Centre for Cells - rbc, platelets, and most wbc. Mineral Reservoir - calcium and phosphorous storehouse.`

Question 7

Axial vs Appendicular

Answer 7

Axial - 80 bones, mainly comprised of vertebral column, rib cage, most of skull.
Appendicular - 126 bones, mainly comprised of limbs and their girdles.

Question 8

2 functions of axial skeleton?

Answer 8

1. support and protect organs in anterior and posterior cavities.
2. Creates surface for attachment of muscles.

Question 9

5 main parts of the axial skeleton?

Answer 9

1. Skull (Cranium, face, Auditory Ossicles)
2. Hyoid Bone
3. Vertebral Column
4. Sternum
5. Ribs

Question 10

10 main parts of the appendicular skeleton? 6 major regions?

Answer 10

1. Pectoral Girdle *
2. Arms (and Forearms)*
3. Wrists
4. Hands *
5. Fingers
6. Hips /Pelvis *
7. Legs (and Thighs) *
8. Ankles
9. Feet (and Ankles) *
10. Toes

Question 11

1 function of appendicular skeleton?

Answer 11

Movement

Question 12

What girdles do the arms and legs go in, respectively? What cavities do the humerus and femur go in, respectively?

Answer 12

Arms - Pectoral Girdles (shoulder blades and clavicle)
Legs - Pelvic Girdle ( hip bones and sacrum)
Humerus - Glenoid Cavity
Femur - Acetabulum Cavity

Question 13

What does cartilage do?

Answer 13

Allows smooth movement of bones.

Question 14

What does periosteum do?

Answer 14

Layer of connective tissue covering the bone that allows bone to connect to bone or muscles.

Question 15

What does the medullary cavity do?

Answer 15

Contains red and yellow bone marrow used to create rbc, platelets, and most wbc.

Question 16

What does compact bone do?

Answer 16

Is responsible for bone’s structural integrity.

Question 17

What is the diaphysis?

Answer 17

The shaft of the bone

Question 18

What is the epiphysis?

Answer 18

Very end of the long bone

Question 19

What is cancellous bone?

Answer 19

Small, cavity-like spaces in the bone that contain bone marrow and distribute force well

Question 20

What is the cortex?

Answer 20

Dense, smooth exterior of bone.

Question 21

What are trabeculae?

Answer 21

Bony fibres running throughout the cancellous tissue

Question 22

What are epiphyseal plates?

Answer 22

Black spaces between the diaphysis and epiphysis on x-rays​, occur at various locations at the epiphyses of long bones​, make growth possible.

Question 23

What are epiphyseal lines?

Answer 23

Appears as a solid epiphysis (no black spaces) on an x-ray ​when epiphyseal plates fuse, inhibit growth.​

Question 24

Define Landmark

Answer 24

Ridge, bump, groove, depression, or prominence on the surface of a bone.

Question 25

Function of landmarks?

Answer 25

Leads to location of other body structures, allows for passage of blood vessels and nerves; joints between bones; and attachment of ligaments, muscles, and tendons.

Question 26

5 types of bones?

Answer 26

1. Long bones - arms and legs
2. Flat bones - flat and thin (parietal bone)
3. Irregular bone - can’t otherwise be categorized, oddlooking (sphenoid)
4. Sesamoid - small, flate bones wrapped with tendons, move over bony surfaces (patella)
5. Short bones - common in wrists (carpals)

Question 27

Who are the most likely targets for bone fractures? Why?

Answer 27

The old and the young. The old because of loss of calcium, the young because calcification is still incomplete.

Question 28

3 types of fractures

Answer 28

1. Simple, 2. Compound, 3. Comminuted

Question 29

Difference between simple, compound and comminuted fractures?

Answer 29

Simple - no separation of bone, only crack or break. Compound - bone is separated into different pieces
Comminuted - when the broken ends of the bone are shattered

Question 30

When does a stress fracture occur and give an example

Answer 30

A stress fracture occurs when the muscles in a limb are to exhausted to absorb shock and transfer the shock to the bone, causing the development of tiny cracks. Ex. long distance running.

Question 31

What is osteoporosis?

Answer 31

A degenerative condition involving low bone mass as well as deterioration of bone tissue. Causes bone fragility, susceptibility to bone fractures especially in hips, spine and wrist.

Question 32

What else is deterioration of bone tissue know as?

Answer 32

Porous bone.

Question 33

Regarding osteoporosis, what happens to older women?

Answer 33

After menopause they can lose 20% bone mass in 5-7 years, making them more susceptible.

Question 34

Defense for osteoporosis?

Answer 34

Build strong bones during childhood and adolescence, balanced diet rich in calcium and vitamin D, weight bearing exercises, no smoking and alcohol, bone density testing and medication when appropriate.