Question

Pubis in the frog’s pelvic girdle is actually a
A) Calcified cartilage
B) Cartilaginous bone
C) Bone
D) None of the above

Answer 1

Hint:Pubis is initially hyaline, but because of the accumulation of calcium salts in the matrix, it later becomes this form.

Complete answer:
First we should know about the frog's pelvic girdle to answer this question. The pelvic girdle of the frog is found in the posterior part of the trunk. This offers protection for the hindlimbs. It is V-shaped and consists of two halves, each known as os-innominatum, and they are similar. Each os-innominatum consists of three bones that form the disc and the acetabulum, and those three bones are the pubis, ilium, and ischium.
Now, let us find the solution from the options-
Calcified cartilage is present in the older frog's pubis. It is a modified hyaline cartilage which, due to calcium deposition, is hard and non-elastic.
Sternum is composed of cartilage and bone in frogs and is only bound to the pectoral girdle. Thus, the options B and C are incorrect.

Thus, the correct answer is option (A) Calcified cartilage

Note: Ilium is considerably elongated and forms the majority of each os-innominatum. Pubis is considerably reduced. It is a triangular piece of calcified cartilage which forms a small portion of the acetabulum and the central part of the disc. Ischium is a broader, slightly oval bone and in the centre, both the ischia fuse and form one-third of the disc and acetabulum.