Lesson 5

Question 1

the process by which bone forms

Answer 1

ossification

Question 2

ossification four principal situations

Answer 2

initial formation of bones
growth of bones
remodeling of bones
repair of fractures

Question 3

bone development begins during ___ to ___ week

Answer 3

6th to 7th

Question 4

two types of ossification

Answer 4

intramembranous and endochondral

Question 5

bone formation within hyaline cartilage that develops from mesenchyme

Answer 5

endochondral ossification

Question 6

primary ossification center of a long bone

Answer 6

diaphysis

Question 7

secondary ossification occurs in the

Answer 7

epiphysis

Question 8

bone formation directly within mesenchyme arranged in a sheetlike layers that resemble membranes

Answer 8

intramembranous

Question 9

epiphyseal plate consist of four zones

Answer 9

RPHC
zone of:
resting cartilage
proliferating cartilage
hypertrophic cartilage
calcified cartilage

Question 10

Because of the ce division in the ________________, the diaphysis of a bone _____ in ______.

Answer 10

epiphyseal growth plate
increases
length

Question 11

Bone grows in __________ due ti addition if new bone tissue by _________ around the outer surface of the bone. This process is called _________.

Answer 11

thickness/diameter
periosteal osteoblasts
appositional growth

Question 12

other term for ossification

Answer 12

osteogenesis

Question 13

intra means

Answer 13

within membrane

Question 14

“little fountains”

Answer 14

fontanels

Question 15

chondro means

Answer 15

cartilage

Question 16

mesenchyme is transformed into ________ which produce a hyaline cartilage matrix

Answer 16

chondroblasts

Question 17

age of ____, bone loss exceeds bone gain

Answer 17

35

Question 18

Endochondral Ossification of a Long bone

Answer 18

1. A cartilage model, with the general shape of the mature bone, is produced by chondrocytes. A perichondrium surrounds most of the cartilage model.
2. The chondrocytes enlarge, and cartilage is calcified. A bone collar is produced, and the perichondrium of the diaphysis becomes the periosteum.
3. A primary ossification center forms as blood vessels and osteoblasts invade the calcified cartilage. The osteoblasts lay down bone matrix, forming trabeculae.
4. Secondary ossification centers form in the epiphysis of long bones.

Question 19

Intramembranous ossification

Answer 19

1. In center of ossification, osteoprogenitor cells develop into osteoblasts.
2. Osteoblasts secrete organic matrix called OSTEOID.
3. The secretion stops and it develops into Osteocytes.
4. Calcium and other mineral salts are deposited to calcify the bone.
5. After calcification, bone matrix develops into Trabeculae – fuse with one another to create spongy bone.
6. Spaces between trabeculae fill with vascularised connective tissue is differentiated into RBM.
7. Mesenchyme condenses and develops into the PERIOSTEUM.
8. Superficial layers of the spongy bone remains at the center.

Question 20

hyaline cartilage that covers the epiphysis

Answer 20

acticular cartilage

Question 21

• type of dense connective tissue that can withstand considerable tension
• no canals, no Haversian system, avascular
• semi-opaque

Answer 21

Cartilage

Question 22

most common, glossy, weakest cartilage

Answer 22

Hyaline

Question 23

strongest, serves as cushion to some joints with limited motion

Answer 23

Fibrous

Question 24

with elastic fibers/some which has some firmness

Answer 24

Elastic