Lecture 3 - Structure of the skeleton

Question 1

What are the functions of the skeleton?

Answer 1

1. Support
2. Structure
3. Protection
4. Red blood cell formation
5. Movement

Question 2

What are the two types of bone tissue and their properties?

Answer 2

1. Compact bone = dense and strong. Good at transmitting force in one direction - the compact bone can take all of the weight coming down on it and can condense it.
2. Cancellous bone = light, spongy bone. Good for shock absorbing. Resists and channels forces that come from multiple directions. Ends of the force spreads out into the oblique direction of the bone whereas compact is direct sharp.

Question 3

What are the four bone classes?

Answer 3

1. Long bone
2. Short bone
3. Flat bone
4. Irregular bone

Question 4

Long bones are :

Answer 4

1. Longer than they are wide
2. Composed of wider epiphyses and a longer, narrower diaphysis
3. Act as levers for movement
4. Thicker compact bone in diaphysis
5. Medullary cavity - opening where we have space for marrow

Question 5

What are epiphyses?

Answer 5

The round part of a bone

Question 6

What is diaphysis?

Answer 6

The long thin shaft of a bone

Question 7

Short bones are :

Answer 7

1. Close to equal width and length
2. Mostly cancellous bone
3. Weight bearing (taking weight and force from multiple directions)

Question 8

Flat bones are :

Answer 8

1. Function usually for muscle attachment
2. Allows large and purposeful muscles to attach to it
3. Thin plates of compact bone (some cancellous too)

Question 9

Irregular bones are :

Answer 9

1. Various shapes and sizes

2. Often have foramina (holes, e.g vertebrae, pelvic bone, hip bone)

Question 10

What are the two divisions of the skeleton and their functions

Answer 10

1. Axial skeleton = bones of core and trunk (skull, sternum, ribs, vertebral column, sacrum, coccyx)
2. Appendicular = bones of your limbs. Allow you to move and are most important for movement.

Question 11

The vertebral column….

Answer 11

1. Keeps the trunk upright
2. Lots of muscle/ligament attachments
3. Supports head

Question 12

What are the divisions of the vertebral column and how many bones are in each?

Answer 12

1. Cervical (7 bones)
2. Thoracic (12 bones)
3. Lumbar (5 bones)

Question 13

How do the limbs attach to the axial skeleton?

Answer 13

Girdle. Bones girdle is to hold your appendicular skeleton to axial skeleton.

Pectoral girdle = attaches to your shoulder (clavicle and scapula)

Pelvic girdle = attaches hip bones and sacrum

Question 14

What are the three different bones in the hip and where they are located?

Answer 14

1. Ilium - superior portion of your pelvis
2. Pub is - anterior part of pelvis that connects to opposite hip bone
3. Ischium - part of pelvis that you sit on