The shape of eyeball is
**Core Concept**
The eyeball is a complex, three-dimensional structure that maintains its shape due to the interaction of various anatomical components. The eyeball is characterized by its spherical shape, which allows it to refract light effectively and project clear images on the retina.
**Why the Correct Answer is Right**
The eyeball is shaped like an oblate spheroid, meaning that it is slightly flattened at the poles (top and bottom) and bulging at the equator (middle). This shape is maintained by the tension of the sclera, the tough, white, fibrous tissue that forms the outer layer of the eyeball. The sclera provides structural support and protection to the delicate inner structures of the eye.
**Why Each Wrong Option is Incorrect**
**Option A:** The eyeball is not a prolate spheroid, which would be elongated at the poles and flattened at the equator. This shape would not allow for proper light refraction and image formation.
**Option B:** The eyeball is not a cube, which would not provide the necessary curvature for light refraction and would not accommodate the complex anatomy of the eye.
**Option C:** The eyeball is not a cone, which would not allow for the necessary depth and curvature for proper vision.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the shape of the eyeball is crucial for maintaining proper vision and preventing conditions such as myopia (nearsightedness) and hyperopia (farsightedness), which can result from irregularities in the shape of the eyeball.
**Correct Answer: C. Ellipsoid**