Chapter 7, Problem 1DYB

_____ 1. Which bone is formed from intramembranous bone growth?

1. a. femur
2. b. rib
3. c. os coxae (hip bone)
4. d. frontal bone

Summary Introduction

Introduction:

The process of formation and development of bone inside the mesenchyme is called intramembranous ossification. The mesenchyme has an abundance of ground tissue and mesenchymal cells.

Answer to Problem 1DYB

Correct answer:

The intramembranous ossification leads to the growth of frontal bone. Therefore, option d . is correct.

Explanation of Solution

Reason for the correct statement:

The intramembranous ossification got initiated with the thickening and condensation of the mesenchyme along with a good supply of blood through capillaries. The formation of ossification centers starts in the dense regions of mesenchyme during the development. The spongy and compact bones are formed in layers forming the flat bones. The frontal bone is one of the flat bones of the skull. Hence, the frontal bone is developed from “intramembranous ossification”.

Option d. is given as “frontal bone”.

Hence, option d. is correct.

Reasons for incorrect statements:

Option a. is given as “femur”.

The process, by which most of the bones are produced by hyaline cartilage, is called “endochondral ossification”. The formation and development of femur bone occur by the process of endochondral ossification. Hence, option a. is incorrect.

Option b. is given as “rib”.

The formation and development of rib bone occur by the process of endochondral ossification. Hence, option b. is incorrect.

Option c. is given as “os coxae (hip bone)”.

The formation and development of hip bone occur by the process of endochondral ossification. Hence, option c. is incorrect.

Hence, options a., b., and c. are incorrect.

Conclusion

The flat bones are formed by intramembranous ossification. The frontal bone of skull is one of the flat bones.