The Skeletal System

Question 1

What are the function of the skeletal system?

Answer 1

1. Framework to support soft tissue.
2. protection
3. provides surface for muscle attachments
4. carries out homeopoiesis - red bone marrow produces blood cells
5. stores calcium phosphorus, and other minnerals for homeostasis.
6. stores energy in adipose tissue in yellow bone marrow.

Question 2

What are the types of bone?

Answer 2

long
short
flat
irregular

Question 3

Describe long Bone

Answer 3

• greater length than width.
• compact bone prevalent; but spongy bone at the ends
• has epihyses (distal and proximal ends) separated from diaphysis (shaft).
• contains a medullary cavity and articular cartilage.

Question 4

Give an example of long bone.

Answer 4

humerous, radius, ulna, femur, tibia, fibula.

Question 5

What covers the diaphysis (shaft)?

Answer 5

a tough periosteum with fibrous layer of dense irregular connective tissue and osteogenic layer containing bone-froming cells.

Question 6

Function of periosteum.

Answer 6

protects the bone and helps to nourish bone tissue while assisting in repairing fractures.

Question 7

What do red marrow, yellow marrow and endosteum bring in the medullary cavity?

Answer 7

Red Marrow - found at the ends of long bone: blood cells are produced.
Yellow Marrow - has adipose tissue for energy and can change to red marrow during stress.
Endosteum - lines the cavity and is composed of reticular CT.

Question 8

What does the articular cartilage do in long bones.

Answer 8

covers epiphysis to provide frition-free movement in a joint.

Question 9

Describe a short bone.

Answer 9

tend to be cube-shaped and have nearly equal length and width. spongy bone is surrounded by a thin layer of compact bone.

Question 10

examples of short bones.

Answer 10

carpals in the wrist; and tarsals in the ankle.

Question 11

Describe flat bones.

Answer 11

thin, bony plates that provide extensive areas for muscle attachment.
the parallel plates of compact bone enclose a spongy diploe filled with red marrow.

Question 12

examples of flat bones.

Answer 12

cranial bones, sternum, ribs, scapulae.

Question 13

Describe irregular bone.

Answer 13

tend to vary in amount of compact bone and spongy bone and come in a variety of odd shapes.

Question 14

examples of irregular bones.

Answer 14

vertebrae and some facial bone.

Question 15

What are the types of bone cells?

Answer 15

osteogenic, osteoblasts, osteocytes, osteoclasts.

Question 16

Define osteogenic cells.

Answer 16

stem cells in the periosteum and in the endosteum that differentiate into osteoblasts.

Question 17

Define osteoblasts.

Answer 17

bone-forming cells that secret the collagen fibers and organic matter that is needed to calcify bone tissue contains RER and secretory vesicales.

Question 18

Define osteocytes.

Answer 18

mature bone cells that are derived from osteoblasts.

Question 19

What is the function of osteocytes?

Answer 19

to maintain the daily cellular activities of bone tissue; such as nutrient exchange and waste exchange.

Question 20

Define osteoclasts.

Answer 20

bone-dissolving cells that function in bone resorption and remodeling.

Question 21

What is the bone matrix composed of?

Answer 21

inorganic hydroxyapatite for calcification of mineralization of bone. and crystallized calcium phosphate is responsible for bone hardness.
Also organic materials such as collagen and other proteins that are responsible for bone flexibility.

Question 22

How is compact bone arranged?

Answer 22

in functional osteons that stack on top of one another (haversian system) and function like tiny-weight-bearing pillars.

Question 23

How is spongy bone arranged?

Answer 23

in a network of bone trabeculae plates.

Question 24

Describe the Central (haversian) canal in compact bone.

Answer 24

runs the entire length of an osteon and contains blood vessels and nerve fibers.

Question 25

Describe the perforating (Volkmann) canals in compact bone.

Answer 25

link the blood vessels and nerves in a central canal with blood vessels and nerves in the medullary cavity and periosteum.

Question 26

What does the space between the trabeculae fill with in spongy bone?

Answer 26

red bone that provides nourishment to osteocytes located in lacunae.

Question 27

Describe concentric lamellae in compact bone.

Answer 27

rings of hard, calcified material around a central canal.

Question 28

What are the benefits to spongy bone?

Answer 28

provides consierable strength without additional weight and it is only location for the res bone marrow that produces blood cells in adults.

Question 29

Define lacuna in compact bone.

Answer 29

tiny spaces betweent the lamellae and contain osteocytes (living cells).

Question 30

Define canaliculi in compact bone.

Answer 30

tiny channels that connect lacunae, so osteocytes can distribute nutrients to one another and transfer wastes to nearby blood vessels to continue metabolic processes.