Pronunciation: [ɹˈɛtɪnə͡lz] (IPA) 
The spelling of "retinals" is fairly straightforward once you understand the pronunciation. In IPA phonetic transcription, the word is spelled /ˈrɛtɪnəlz/. The first part, "retin," has a short "e" sound followed by a "t" and an "i" with a short "i" sound. The ending, "-als," has a long "a" sound followed by an "l" and an "s." "Retinals" refers to a class of molecules involved in vision, found in the retina of the eye.
Retinals, also referred to as retinaldehyde or retinal, are a group of organic compounds that belong to the family of retinoids. They are derived from Vitamin A and play a crucial role in various biological processes, particularly in vision and cellular growth and development.
In the context of vision, retinals are essential components of the visual pigments found in the retina of the eye. They are responsible for the absorption of light and the initiation of the visual signaling cascade. Specifically, retinals combine with specific proteins called opsins to form light-sensitive pigments known as rhodopsins or cone pigments, depending on their location in the retina. These pigments undergo a molecular change when exposed to light, enabling them to transmit signals to the brain.
Apart from their role in vision, retinals also participate in cellular growth and differentiation. They act as signaling molecules that regulate gene expression and cell proliferation. Retinals have been identified to be involved in processes such as embryonic development, tissue maintenance, and wound healing. Additionally, retinals are crucial for maintaining healthy skin, as they contribute to the production of collagen and promote skin cell formation.
Due to their biological significance, retinals have been studied extensively, and their therapeutic potential has been recognized in various fields, including ophthalmology, dermatology, and regenerative medicine. Researchers have developed synthetic retinals and derivatives for medical and cosmetic applications, aiming to treat visual impairments, skin disorders, and promote tissue regeneration.
