Lecture 10: Bone Histology Flashcards Preview

04. MSK Exam 2 Final > Lecture 10: Bone Histology > Flashcards

Flashcards in Lecture 10: Bone Histology Deck (45)
Loading flashcards...
1

What is another name for Mature or Secondary bone?

Lamellar Bone

2

What exists between the inner and outer circumferential lamellae, outside of the individual osteons?

Interstitial lamellae

3

What can be found in the inner layer of the periosteum?

 

What is this layer called?

Osteoprogenitor cells

 

Osteogenic layer

4

Where do osteoprogenitor cells come from?

Mesenchyme

5

What can be found in the endosteum?

Osteoprogenitor cells

6

What are the four steps of intramembranous ossification?

1: Mesenchyme condenses due to signaling molecules

2: Osteoblasts differentiate and begin forming osteoid around the blood vessels inside the condensed mesenchyme

3: Osteoblasts begin calcifying that osteoid forming a honeycomb around the blood vessels

4: Bone develops outward until the spongy bone is covered

7

What can be found in the outer layer of periosteum?

 

What is this layer called?

Blood Vessels and Nerves

Fibroblasts and Collagen

Sharpey's Fibers

 

Fibrous layer

8

What cells activity is associated with high Alkaline Phosphatase activity?

Osteoblast activity

(specifically as they are becoming osteocytes, they give off "AlkPhos")

9

Where is red bone marrow primarily found in adults and children?

In the flat bones in adults, and in all bones in young children

10

What do osteoprogenitor cells differentiate into?

Osteoblasts

11

What lamellae are adjacent to the endosteum?

The Inner Circumferential Lamellae

12

Actions of which zone of endochondral ossification cause lengthining of the bone?

Zone of hypertrophy

13

What are the four steps of bone fracture repair?

1: Hematoma Formation

2: Soft (Fibrocartillagenous) callus formation

3: Hard (bony) callus formation

4: Bone remodeling

14

Where are osteoprogenitor cells found?

Inner layer of the periostium

Endosteum

15

What is the normal function of FGFR3?

 

What changes to cause Achondroplasia?

FGFR3 stops growth during adulthood

 

It activates prematurely

16

What is the heredity of Achondroplasia?

Autosomal Dominant

17

What are Sharpey's fibers, and what is their function?

They are collagen fibers that penatrate the outer circumferential lamellae.

 

They anchor they periosteum to the bone itself

18

Where would you find the endosteum?

Covering the spongey walls.

(Said another way, on the walls of the medullary cavity)

19

What lamellae lie just deep to the periosteum in bone?

The Outer Circumferential Lamellae

20

How do osteoclasts resorb bone? (Two enzymes)

They create a localized secluded acidic environment using H+-ATPase, then degrade the organic matrix via Cathepsin K Protease

21

Where do osteoclasts come from?

The Monocyte Lineage

22

In what zone of endochondral ossification is the medullary cavity produced by osteoclasts?

Zone of resorption

(Osteoclasts eat the dead chondrocytes)

23

What might be a more primary disease that could cause Osteomalacia?

GI disease (Calcium / Vitamin malabsorption)

24

What causes Rickets?

Calcium or Vitamin D deficiency during growth, causing deficient mineralization of cartilage in the growth plate

25

What do we call Vitamin D or Calcium deficiency in adults?

Osteomalacia

26

When might osteoprogenitor cells be the most active?

During times of bone repair

27

In endochondral ossification, what surrounds the cartilagenous blueprint?

Perichondrium

28

What separates the interstitial circumferential lamellae from the osteon?

The cement line

29

What lies at the center of the osteon?

The Haversian Canal

30

What are the symptoms of Rickets?

Delayed closure of the fontanelles

Bowed lower limbs

Bossing of the skull

Bowing of distal radius and ulna