Question

Typical vertebra of human is:
A. Amphiplatyan
B. Amphicoelous
C. Procoelous
D. None of these

Answer 1

The humans come under the class vertebra. All vertebrates constitute Amphiplatyan type of vertebra on the basis of type of centrum i.e. basic structure present in their body.

Complete answer:
All vertebrates possess backbone/ vertebral column, extending from skull to posterior end of trunk. It consists of several small rings like segmented bony pieces called vertebrae. All vertebrae have same basic structure as:

Bony centrum- facing anterior to vertebral column.
Vertebral arch- Joining all posterior extensions from the vertebral body.
Vertebral foramen- through which the spinal cord passes.
Transverse process- lateral projection of body.
Spinous process- Single posterior projection from the body.
Superior and inferior articular process- Lateral to vertebral foramen and allow vertebrae to form joint with adjacent vertebrae.
Type of vertebrae can be of different types depending on the basis of types of centrum present. These can be categorized as:
Procoelous: Centrum is concave in front and convex behind. E.g. - Frog.
Opisthocoelous: Centrum is convex in front and concave behind. E.g. - Salamandra.
Amphicoelous: Centrum is concave on both ends. E.g. - Sharks.
Heterocoelous Anterior face is convex from above downward and concave from side to side. E.g.-vertebrae of modern birds.
Acoelous- Centrum is convex on both ends. E.g. - Frog’s 9th vertebrae.
Platycoelous: Centrum is flat at front and concave at hind end. E.g. - Some mammals.
Amphiplatyan: Centrum is flat on both ends. E.g. - All vertebrates in man.

Thus the correct answer is Amphiplatyan i.e. option A.

Note:
The skeletal system consists of a framework of bones and a few cartilages. Our human body is formed by 26 serially arranged units of vertebral column placed dorsally with Amphiplatyan type of vertebral arrangement.