MMB (048) Normal and Abnormal Bone Growth

Question 1

Answer 1

Question 2

which is wooven and lamelar bone ?

Answer 2

Question 3

Answer 3

Question 4

Answer 4

Question 5

explain Intramembranous ossification in 4 points

Answer 5

Question 6

Bones formed by Intramembranous Ossification ?

Answer 6

Question 7

Bones formed by Endochondral Ossification ?

Answer 7

Question 8

Answer 8

Question 9

Answer 9

Question 10

Answer 10

Question 11

Answer 11

Question 12

Answer 12

Question 13

Answer 13

Question 14

Answer 14

Question 15

Answer 15

Question 16

Answer 16

Question 17

Answer 17

Question 18

• The most common disease of the growth plate and the major cause of dwarfism ?

Answer 18

Achondroplasia

Question 19

Inheritance of Achondroplasia ?

Answer 19

autosomal dominant

Question 20

Pathogenesis of Achondroplasia ?

Answer 20

-In normal development , FGFR3 has a negative regulatory effect on bone growth.

In achondroplasia, the mutated form of the receptor is constitutively active and this leads to severely shortened bones

Question 21

Fate of Homozygous infants with achondroplasia gene mutation ?

Answer 21

Homozygous infants normally die at birth or soon after from respiratory insufficiency due to a small chest cavity

Question 22

Answer 22

Question 23

Morphologic Features of Achondroplasia ?

Answer 23

Question 24

The genes that code for the α1 and α2 chains of type 1 collagen ?

Answer 24

COL1A1 and COL1A2

Question 25

Other organs rather than bone affected in Osteogenesis imperfecta ?

Answer 25

joints, eyes, skin and teeth are affected as well

Question 26

The spectrum of severity for Osteogenesis imperfecta ?

Answer 26

Question 27

Question 28

Question 29

Bone microscopy of Osteogenesis imperfect-a patient ; describe.

Answer 29

Question 30

Clinical picture of Cretinism ?

Answer 30

• Disproportionally short limbs • Large head due to delayed closure of fontanelles • Mental impairment

Question 31

Cause of cretinism ?

Answer 31

• Results from maternal iodine deficiency

Question 32

Question 33

Acromegaly – signs & symptoms ?

Answer 33

Question 34