A&P Ch.6 The Skeletal System

Question 1

What are the 5 functions of the the skeletal system?

Answer 1

1. Support
2. Storage of calcium salts and lipids (yellow marrow)
3. Blood cell production (red marrow)
4. Protection
5. Leverage (levers for skeletal muscles)

Question 2

What are the 4 types of bones?

Answer 2

1. Long bone (ex. Femur, typical bone)
2. Flat bone (ex. Parietal bone)
3. Irregular bone (ex. Vertebra)
4. Short bone (ex. Carpals)

Question 3

Typical Structure of the long bones:

Diaphysis

Answer 3

Central shaft

Contains the marrow cavity

Question 4

Typical Structure of the long bones:

Epiphyses

Answer 4

The expanded portion at each end covered by articular cartilage

This area is what articulates with an adjacent bone at a joint.

Question 5

Typical structure of the long bone:

Marrow cavity

Answer 5

Contains the BONE MARROW.

MARROW CAVITY is surrounded by the DIAPHYSIS

Question 6

Typical structure of a long bone:

Compact bone

Answer 6

Solid bone

Forms the DIAPHYSIS

Question 7

Typical structure of a long bone:

Spongy bone or cancellous bone

Answer 7

Resembles a network of bony rods or struts separates by spaces.

The spongy bone fills the EPIPHYSES

Has no osteons

Question 8

Typical structure of a long bone:

Periosteum

Answer 8

Forms the OUTER SURFACE of the bone

Ligaments and tendons attach here

Provides a route for circulatory and nervous supplies

Participated in bone growth and repair

Has a fibrous outer layer and a cellular inner layer

Question 9

Typical structure of a long bone:

Endosteum

Answer 9

Lines the marrow cavity and other internal surfaces.

Active during bone growth and repair/remodeling

Question 10

Osteocytes

Answer 10

Mature OSTEOBLASTS cells

Bone cells

Arranged in a concentric layer (circular layer) around the CENTRAL CANAL

Question 11

Lacunae

Small pockets

Answer 11

House the osteocytes

found in both SPONGY & COMPACT bone

Located between the LAMELLAE

Question 12

LAMELLAE

Answer 12

Narrow sheets of calcifies matrix

Question 13

Canaliculi

Small channels

Answer 13

Radiate through the matrix

Interconnect LACUNAE and link them to nearby blood vessels

Question 14

Osteon

Haversian system

Answer 14

The basic functional unit for compact bone

OSTEOCYTES are arranged in a concentric layer (circular pattern) with in the OSTEON

Question 15

Central canal

Haversian canal

Answer 15

Contains one or more blood vessels that connect to the PERFORATING CANAL

LAMELLAE run cylindrically parallel to the long axis of the CENTRAL CANAL

Question 16

Perforating canal

Answer 16

Provides a pathway for the blood vessels of the CENTRAL CANALS to connect and supply the vessels of the PERIOSTEUM and the MARROW CAVITY

Question 17

Trabeculae

Answer 17

Rods and plates formed by the LANELLAE with in SPONGY BONES

Not found in the COMPACT BONE

Question 18

Where is a layer of COMPACT BONE not found?

Answer 18

Inside joint capsules where ARTICULAR CARTILAGES are found.

Question 19

This type of bone is found typically where stresses comes from a limited range of direction

Answer 19

Compact bone

Question 20

Functions of the cells:

Osteocytes

Answer 20

Maintain normal bone structure by recycling the calcium salts in the bony matrix surrounding them.

Assists in repairs

Question 21

Functions of the cells:

Osteoclasts

Answer 21

Contain 50 or more nuclei

Bone breakers

Dissolve bone with an acid and enzyme secretion releasing stored minerals back into the system through a process called OSTEOLYSIS or RESORPTION.

Help regulate calcium and phosphate concentrations in the body fluids

Question 22

Functions of the cells:

Osteoblasts

Answer 22

Bone makers

Create bone in a process called OSTEOGENESIS