Chapter 6: Bone Tissue

Question 1

When does bone form

Answer 1

Around the 6th week of embryonic development

Question 2

What is intramembranous ossification

Answer 2

It is the process by which bone forms directly from mesenchymal tissue

Question 3

What is Endochondral Ossification

Answer 3

Process in which bone forms by replacing hyaline cartilage

Question 4

Types of Cells in Bone Tissue

Answer 4

1. Osteoprogenitor cells
2. Osteoblasts
3. Osteocytes
4. Osteoclasts

Question 5

What are Osteoprogenitor Cells

Answer 5

They are
-Bone stem cells
- Only one that undergoes cell division ( Become osteoblasts)

Location
- Inner portion of periosteum
- Endosteum
- Canals of the bone that contains blood vessels

Question 6

What are Osteoblasts

Answer 6

They are

• Bone building cells
• Synthesize and secrete collagen fibers and other organic components
• Initiate calcification
  ( This calcification traps the osteoblasts and transform into osteocytes)

Question 7

What are Osteocytes

Answer 7

They are

-Mature bone cells
-Main cell in the bone tissue
-Maintain daily metabolism ( Exchange of –nutrients and wastes with the blood)
-Do NOT undergo cell division

Question 8

What are Osteoclasts

Answer 8

They are

• Concentrated in endosteum
• Ruffled border
• Releases powerful lysosomal enzymes and acids
• Digest protein and mineral components of extracellular matrix
• Bone resorption
• Part of normal development, growth, maintenance and
  repair of bone
• Help regulate blood calcium level In response to certain hormones
• Used as target cells in osteoporosis

Question 9

What are Flat Bones

Answer 9

Bones that are thin and have a flat shape

Example:

Cranial Skull
Scapulae (Shoulder Blades)
Sternum ( Breastbone)
Ribs

Flat bones serve as a point of attachment for muscles and often protect internal organs

Question 10

What are Irregular Bones

Answer 10

Bones with complex and irregular shapes

Example:

The vertebrae that supports the spinal cord
Many facial bones that contain sinuses

Question 11

What are long bones

Answer 11

Bones that are longer than wider

Example:

Arms: Humerus, Ulna, Radius

Legs: Femur, Tibia, Fibula

Fingers: Metacarpals, Phalanges

Toes: Metatarsals, Phalanges

Question 12

What are Short Bones

Answer 12

Bones with nearly equal length, width, and depth

Examples:

The carpals of the wrist and the Tarsals of the ankles

Question 13

What is a Sesamoid Bone (Think of sesame seed)

Answer 13

Small round bone that develop within tendons

Example:

The patellae (singular = patella) are the only sesamoid bones found in common with every person.

Question 14

What are Pneumatized Bones

Answer 14

Bones that contain spaces lined with mucous membranes