Final answer:
The lens of the human eye is suspended by the ciliary body and zonule fibers which allow it to focus light accurately on the retina. The lens is only supported around its edges to prevent distortion, ensuring clear vision. The vascular tunic, including the choroid and ciliary body, provides support and blood supply to the eye's structural components.
Step-by-step explanation:
How is the Lens Suspended in the Eye?
The lens of the human eye is precisely supported to enable clear vision. It is suspended within the eye by a structure known as the ciliary body, which is attached to the lens by delicate suspensory ligaments, also called zonule fibers. Since light must pass through the lens without distortion, it is critical that the lens is supported only around its edges, akin to the frames of eyeglasses. The ciliary body and zonule fibers work together to allow the lens to change shape, adjusting its focal length to focus light onto the retina, regardless of whether the light source is near or far. Gravity's effect is mitigated by the delicate and equilibrated support given to the lens, preventing it from sagging and thus maintaining the clarity and sharpness of images.
Furthermore, the eye is structured with three layers of tissue commonly known as the fibrous tunic, the vascular tunic, and the neural tunic or retina. The vascular tunic, including the choroid and ciliary body, provides blood supply and supports the lens structurally. In response to light, the iris adjusts the size of the pupil to regulate the amount of light entering the eye. This complex system ensures that light is effectively sensed and focused on the retina for proper vision.