Retinol Youth Renewal Eye Serum | Eye Treatment | Murad

An eye is a sensory organ that allows an organism to perceive visual information. It detects light and converts it into electro-chemical impulses in neurons (neurones). It is part of an organism's visual system.

In higher organisms, the eye is a complex optical system that collects light from the surrounding environment, regulates its intensity through a diaphragm, focuses it through an adjustable assembly of lenses to form an image, converts this image into a set of electrical signals, and transmits these signals to the brain through neural pathways that connect the eye via the optic nerve to the visual cortex and other areas of the brain.

Eyes with resolving power have come in ten fundamentally different forms, classified into compound eyes and non-compound eyes. Compound eyes are made up of multiple small visual units, and are common on insects and crustaceans. Non-compound eyes have a single lens and focus light onto the retina to form a single image. This type of eye is common in mammals, including humans.

The simplest eyes are pit eyes. They are eye-spots which may be set into a pit to reduce the angle of light that enters and affects the eye-spot, to allow the organism to deduce the angle of incoming light.

Eyes enable several photo response functions that are independent of vision. In an organism that has more complex eyes, retinal photosensitive ganglion cells send signals along the retinohypothalamic tract to the suprachiasmatic nuclei to effect circadian adjustment and to the pretectal area to control the pupillary light reflex.

Murad or Mourad (Arabic: مراد) is an Arabic name. It is also common in Armenian, Azerbaijani, Bengali, Turkish, Persian, and Berber as a male given name or surname and is commonly used throughout the Muslim world and Middle East.

Retinol, also called vitamin A₁, is a fat-soluble vitamin in the vitamin A family that is found in food and used as a dietary supplement. Retinol or other forms of vitamin A are needed for vision, cellular development, maintenance of skin and mucous membranes, immune function and reproductive development. Dietary sources include fish, dairy products, and meat. As a supplement it is used to treat and prevent vitamin A deficiency, especially that which results in xerophthalmia. It is taken by mouth or by injection into a muscle. As an ingredient in skin-care products, it is used to reduce wrinkles and other effects of skin aging.

Retinol at normal doses is well tolerated. High doses may cause enlargement of the liver, dry skin, and hypervitaminosis A. High doses during pregnancy may harm the fetus. The body converts retinol to retinal and retinoic acid, through which it acts.

Retinol was discovered in 1909, isolated in 1931, and first made in 1947. It is on the World Health Organization's List of Essential Medicines. Retinol is available as a generic medication and over the counter. In 2021, vitamin A was the 298th most commonly prescribed medication in the United States, with more than 500,000 prescriptions.

Treatment may refer to:

• "Treatment" (song), a 2012 song by Labrinth
• Film treatment, a prose telling of a story intended to be turned into a screenplay
• Medical treatment also known as "therapy"
• Sewage treatment
• Surface treatment or surface finishing
• Water treatment
• Treatment group in design of experiments

Youth is the time of life when one is young. The word, youth, can also mean the time between childhood and adulthood (maturity), but it can also refer to one's peak, in terms of health or the period of life known as being a young adult. Youth is also defined as "the appearance, freshness, vigor, spirit, etc., characteristic of one, who is young". Its definitions of a specific age range varies, as youth is not defined chronologically as a stage that can be tied to specific age ranges; nor can its end point be linked to specific activities, such as taking unpaid work, or having sexual relations.

Youth is an experience that may shape an individual's level of dependency, which can be marked in various ways according to different cultural perspectives. Personal experience is marked by an individual's cultural norms or traditions, while a youth's level of dependency means the extent to which they still rely on their family emotionally and economically.