Bone formation

Question 1

Skeletal System Components and Functions

Answer 1

Made of bones, cartilage, ligaments. Each bone is an organ because it contains blood, bone connective tissue, nerves, lymph vessels, etc.

1. Support
2. Protection
3. Mineral storage
4. Triglyceride/lipid storage (yellow marrow)
5. Red and white blood cell formation called hemopoiesis (red marrow)
6. Leverage (assistance in movement)

Question 2

Components of axial skeleton

Answer 2

Skull, thoracic cage, vertebral column

Question 3

Components of appendicular skeleton

Answer 3

Upper limbs, lower limbs, pelvic girdle, pectoral girdle

Question 4

Long bone examples

Answer 4

Longer than they are wide

-femur, tibula, fibula, humerus, ulna, radius, metacarpals, metatarsals

Question 5

Short bones

Answer 5

Almost equal in length and width

-Carpals (ankle), tarsals (wrist)

Question 6

Flat bones

Answer 6

Relatively flat but may be curved

-sternum, ribs

Question 7

Irregular bones

Answer 7

Complex shape

-vertebra

Question 8

Sesamoid bones

Answer 8

Forms where there is friction, tension, or stress

-patella

Question 9

Sutural bones

Answer 9

Bones found between sutures of the skull

Question 10

Endosteum (anatomy of long bone)

Answer 10

Lines the inner surfaces of bone, including medullary cavity, trabecullae of spongy bone, and canals of compact bone

Contains osteogenic cells (important for bone regrowth/ remodeling)

Question 11

Periosteum

Answer 11

Connective tissue membrane that covers the external surface of bone. It is attached to the bone matrix via perforating fibers.

Contains outer fibrous layer + inner osteogenic layer (important for bone growth/ remodeling)

Question 12

Bone composition

Answer 12

Bone is made up of connective tissue, which makes up the ECM (ground substance/ minerals and collagen fibers) and cells (osteogenic cells, osteoblasts, osteocytes, osteoclasts)

Question 13

Osteogenic cells

Answer 13

Made from stem cells (Mesenchymal)

Goes through mitosis nd differentiates into osteoblasts

Question 14

Osteoblast

Answer 14

Differentiated from osteogenic cell

• forms bone by synthesizing organic components of bone matrix: collagen fibers and glycoproteins in the ground substance
• initiates calcification: takes calcium from blood and deposit it within matrix

Question 15

Osteocyte

Answer 15

Derived from osteoblasts

• maintains bone tissue. Mature bone cells
• senses bone microdamage (wear and tear) and mechanical forces. It sends signals to repair

Question 16

Osteoclast

Answer 16

Derived from myloid stem cells

• Breaks down bone (bone resorption)
• releases enzymes and acids that degrade collagen

Question 17

Spongy bone composition

Answer 17

Trabeculae: Irregular lattice of thin plates

Osteocytes housed in lacunae

Question 18

Spongy bone location/ function

Answer 18

Location:

• epiphyses of long bone
• surrounding marrow cavities
• flat/short/irregular bones

Function:

• withstand forces (trabeculae arranged along lines of stress)
• lighten skeleton
• contain red marrow for hemopoiesis

Question 19

Compact bone composition

Answer 19

Solid network of bone organized in concentric ring structures called osteons

Concentric lamellae (around central canal) and circumferential lamellae and interstitial lamellae

*Osteons are straws, while the spaces are filled in with interstitial lamellae

Osteocytes sit within lacunae, and its dendrites sit within canaliculi

Question 20

Compact bone location/function

Answer 20

Location:

• external layer of ALL bones
• diaphysis of long bones

Function:
-gives long bones ability to withstand forces along longitudinal axis