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How does vitamin A support vision in animals?

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Isoprenoid Camphor, an isoprenoid compound classified as a terpenoid ketone, is used in incense and certain medicinal compounds. It is a natural substance obtained from the camphor laurel (*Cinnamomum camphora*), a species of evergreen.

Vitamin A is essential for vision in animals because it serves as the precursor to retinal, a critical component of light-sensitive pigments in the eye.12

In the retina, retinal combines with a protein called opsin to form visual pigments, such as rhodopsin. This process relies on the isoprenoid structure of vitamin A, which allows the molecule to exist in different shapes through cis-trans isomerism.134

When light strikes the retina, it triggers a process called photoisomerization, causing the retinal molecule to change shape. This structural shift induces a change in the opsin protein, which initiates a transduction process that converts light energy into electrical nerve signals, allowing the animal to perceive light.412

Because this cycle is continuous, the eye requires a steady supply of vitamin A to regenerate these pigments. A deficiency in vitamin A leads to low levels of 11-cis retinaldehyde, resulting in night blindness and an inability to adapt to low-light conditions.1453