Question

Dicondylic skull with 10 pairs of cranial nerves occur in
A. Pisces
B. Amphibia
C. Reptilia
D. Mammalia

Answer 1

Hint: Dicondylic means the presence of two of the occipital condyle bones in the base of the skull and the cranial nerves means that they arise directly from the brain only.

Complete Answer:
- We know that Pisces, amphibia, reptile, Mammalia and birds all come under chordates having some similarities and some of the dissimilarities present in them.
- Pisces do not have a Dicondylic skull.
- Amphibians have a Dicondylic skull with the presence of the 10 cranial nerves.
- Reptilia do not have Dicondylic skulls, they have a monocondylic skull making it a wrong option.
- We know that mammalians have Dicondylic skulls with the presence of the 12 cranial nerves. It fulfills the one criterion only hence marking it a wrong option.

So, the correct option is B as they fulfill both the criteria of having a Dicondylic skull as well as have the presence of 10 cranial nerves.

Note: The cranial nerves are the nerves that directly arise from the brain. These two condyle bones help the skull to get a connection with the first vertebra of the vertebral column.