Osteology

Question 1

What are the five functions of the skeleton?

Answer 1

1. Provides a supporting framework for the body
2. Provides attachment points for muscles, creating a lever system that enables body movement
3. Provides protection of vital organs
4. Blood cell formation; red bone marrow produces red and white blood cells and platelets. Bone is richly supplied with blood vessels
5. Mineral storage - calcium and phosphorus

Question 2

What are the major building blocks of the bone?

Answer 2

Calcium carbonate, calcium phosphate, collagen fibers, and water

Question 3

What is the main organic constituent of connective tissue?

Answer 3

Collagen, a protein

Question 3

What is the matrix composed of?

Answer 3

The matrix is about 25% water, 25% protein, and 50% mineral salts

Question 4

What is Bone tissue composed of?

Answer 4

Widely separated cells, called osteocytes, surrounded by matrix.

Question 5

Bone is highly ____ and is continually being ______

Answer 5

Dynamic

Remodeled in response to mechanical stress or even absence of stress.

Question 6

What is the epiphyseal plate and what occurs here?

Answer 6

Longitudinal growth of a bone occurs at the epiphyseal plate, which is a layer of cartilage.

Question 7

What is the protein collagen used for?

Answer 7

The main organic constituent of connective tissue.

Question 8

What is Calcium carbonate, calcium phosphate, collagen fibers, and water used for?

Answer 8

The major building blocks of the bone.

Question 9

What is osteocytes used for?

Answer 9

Composes bone tissue.

Question 10

What is the epiphyseal plate and what occurs here?

Answer 10

A layer of cartileage

Longitudinal growth of bone

Question 11

What gradually gets replaced by bone?

Answer 11

Proliferating cartilage cells

Question 12

Compare the bones to physically active individuals to sedentary individuals.

Answer 12

The bones of physically active individuals tend to be denser and therefore more mineralized than those of sedentary individuals of the same age and gender.

Question 13

Describe long bones.

Answer 13

Most of the bones of the upper & lower extremities are of this type (e.g. humerus, radius, ulna, metacarpals, femur, tibia, metatarsals, phalanges).
Longer than they are wide.
Hallow of shaft is made of compact bone, being filled with yellow marrow.
Ends of bones composed of spongy or cancellous bone which contains red marrow

Question 14

Describe short bones.

Answer 14

Wrist (carpals) and ankle (tarsals).

Composed of spongy bone covered by a shell of compact bone.

Question 15

Describe flat bones.

Answer 15

Face and skull, scapula, ribs, sternum, ilium.
Have broad surface for muscle attachment or protection of underlying organs.
Consist of two plates or tables of compact bone w/a thin layer of spongy bone sandwiched between them.

Question 16

Describe irregular bones.

Answer 16

Bones that do not fit into any of the other 3 categoris. The 26 vertebrae, sacrum, coccyx, and bones of the ears are classified as irregular bones.

Question 17

What is the purpose of the vertebrae column?

Answer 17

Provides flexible support for the trunk & protects spinal cord.

Question 18

How many vertebrae are there and the names of the different segments?

Answer 18

33 vertebrae but 26 distinct bones -> the 5 sacral vertebrae fused and the four coccygeal vertebrae fused
5 segments:
7 cervical vertebrae
12 thoracic vertebrae
 5 lumbar vertebrae
5 sacral vertebrae
4 coccygeal vertebrae

Question 19

Why does the vertebrae get thicket?

Answer 19

Due to more weight

Question 20

How do the vertebrae articulate with one another?

Answer 20

By means of facets on the processes of neural arches “synovial joint” and by means of intervertebral discs between the vertebral bodies (cartilaginous joints)

Question 21

What is the function of intervertebral discs?

Answer 21

Shock absorbers and allow slight movement so vertebral column is flexible & resilient.

Question 22

What are the 3 classes of abnormal curves?

Answer 22

Scoliosis - abnormal lateral curvature of vertebral column.
Kyphosis/”hump back” - an exaggerated posterior thoracic curve
Lordosis/”sway back” - an exaggerated anterior lumbar curve

Question 23

Describe fibrous joints

Answer 23

FIXED/IMMOVABLE
Consists of 2 bones united by fibrous tissue, have no joint cavity, & exhibit no movement.
E.g. suture joints in skull & fibrous membrane between borders of radius & ulna

Question 24

Describe cartilaginous joints

Answer 24

SLIGHTLY MOVEABLE
2 bones united by hyaline cartilage or fibrocartilage.
E.g. discs between vertebrae, the symphysis pubis & costal cartilage between ribs and sternum

Question 25

Describe synovial joint

Answer 25

FREELY MOVEABLE
most joints are this type -> vary in detail but same general plan
Joint surrounded by capsule of dense fibrous connective tissue whose fibers are continuous w/those of

Question 26

What are the 2 fxns of synovial fluid?

Answer 26

1) Lubricates the joint surfaces as they slide over each other during joint movements
2) Supplies nutrients to, and removes wastes from, cartilage cells which have no direct blood supply

Question 27

What are ligaments?

Answer 27

Fibrous connective tissue that connects bones together

Question 28

What are tendons?

Answer 28

Fibrous connective tissue that joins muscle to bone

Question 29

What are bursa?

Answer 29

Small sac or cavity filled w/synovial fluid & located @ friction points, especially joints. Most bursae located between tendons & bones