Question

The skull of birds is
A. Monocondylic
B. Dicondylic
C. Amphicondylic
D. None of the above

Answer 1

Hint: Birds are a faction of warm-blooded vertebrates comprising the class Aves, defined by feathers, toothless beaked jaws, the laying of hard-headed eggs, a high metabolism rate, a four-chambered spirit, and a powerful yet portable skeleton.

Complete Answer:
Let us analyse the given options to find out the correct answer.
Option A: Birds possess only one occipital condyle also known as monocondylic and so can twirl their skulls upto 270 degrees. Bird skulls are monocondylic. Therefore, this is the correct option.
Monocondylic skull: The skull which comprises only a solitary occipital condyle. Eg. Skull of reptiles.

Option B: When the skull is connected to the body by two articulated condyles, it's understood as Dicondylic. These categories of skull have two occipital condyles which relate to Atlas (first vertebrae), accordingly known as Dicondylic skull. Human head is the best instance of a Dicondylic skull. Mammals and amphibians are dicondylic. Therefore, this is the incorrect answer.

Option C: Skulls can either be monocondylic or be dicondylic. Therefore, this is an incorrect option.

Hence the correct answer is option A.

Additional Information: The condyles are elliptical or reniform (kidney-shaped) in pattern, and their anterior extremities, authorized along and medialward, are closer jointly than their bottom, and encroach on the basilar fraction of the bone; the posterior extremities extend based to the degree of the inner of the foramen magnum.

Note: The occipital condyles are undersurface projections of the occipital bone in vertebrates, which process in manifestation with the improved facets of the atlas vertebra.