Skeletal System

Question 1

What are the types of Cartilage?

Answer 1

Hyaline, Elastic, Fibrocartilage

Question 2

Characteristics & Functions of Hyaline Cartilage

Answer 2

Mostly collagen fibers; Firm matrix cushions and resists compression

Question 3

Characteristics & Functions of Elastic Cartilage

Answer 3

Mostly elastic fibers; Able to withstand repeated bending

Question 4

Characteristics & Functions of Fibrocartilage

Answer 4

High concentration of collagen fibers; Resits tension and absorbs compressive forces

Question 5

What are the types of bone?

Answer 5

Compact & Spongy Bone

Question 6

What are the differences between compact and spongy bone?

Answer 6

Spongy bone is better for resisting forces from multiple directions, while compact bone resists forces from one direction.

Question 7

What is the structure of spongy bone?

Answer 7

Trabeculae are lined with endosteum and contain osteocytes. Contains red bone marrow

Question 8

What is the structure of Compact Bone?

Answer 8

Made of repeating units called osteons that are long, cylindrical structures running parallel to the long axis of bone.

Question 9

What are osteons made of?

Answer 9

Concentric circles called lamellae

Question 10

Where are lucunae found and what do they do?

Answer 10

Between adjacent lamellae; House osteocytes

Question 11

What are canaliculi?

Answer 11

Connect the lacunae and allow the movement of nutrients and communication between osteocytes.

Question 12

Where is the central canal and what is its function?

Answer 12

In the center of the lamellae; contains blood vessels and nerves

Question 13

What are the classifications of bone by shape?

Answer 13

Long bone, flat bone, short bone, irregular bone

Question 14

Where is the medullary cavity found and what is it filled with?

Answer 14

Found in the diaphysis; filled with yellow marrow (adults) or red marrow (children)

Question 15

Characteristics & Function of the Periosteum

Answer 15

Surrounds outer compact bone; Made of Dense irregular CT

Question 16

Characteristics & Functions of Endosteum

Answer 16

Lines inner surfaces; thinner dense CT; osteogenic

Question 17

What is the Epiphyseal plate?

Answer 17

growth plate: site of active growth in long bone; hyaline cartilage

Question 18

What is the Epipyseal line?

Answer 18

growth plate becomes ossified: growth in length is complete

Question 19

What are the zones of the epiphysis? What are their functions?

Answer 19

Resting zone
Proliferation zone (growth: cartilage undergo mitosis)
Hypertrophic Zone (older cartilage cells enlarge)
Calcification zone (matrix becomes calcified) Ossification Zone (new bone formation)

Question 20

What is the mechanism of fetal bone growth?

Answer 20

Intramembranous ossification: connective tissue membranes are replaced by bone
Endochondral Ossification: hyaline cartilage serves as a template

Question 21

How and where does bone remodeling occur?

Answer 21

Occurs under periosteum and endosteum; osteoclasts secrete HCl which dissolves and releases minerals from matrix, osteoblasts lay down organic osteoid which fills with minerals

Question 22

What is osteoporosis?

Answer 22

Osteoclasts outpace osteoblasts

Question 23

What is osteomalacia?

Answer 23

Characterized in children as bowed long legs; bone matrix not properly mineralized

Question 24

How is Vitamin D utilized in the skeletal system?

Answer 24

1. Vitamin D is synthesized in the skin from UV light 2. Vitamin D travels through bloodstream and facilitates calcium absorption from digestive tract 3. Calcium is used in bone remodeling

Question 25

What is Paget’s Disease?

Answer 25

Excessive remodeling of bone in an unorganized fashion

Question 26

What is the difference between the axial and appendicular skeleton?

Answer 26

Axial: skull, vertebral column, thoracic cage
Appendicular: upper limbs, pelvic girdle, lower limbs