Lumirhodopsin is stable only at temperature below :

Deficiency of Vitamin A causes :

The normal serum concentration of vitamin A in mg/100 ml is :

Retinol and retinal are interconverted requiring dehydrogenase or reductase in the presence of :

A poor source of Vitamin D is:

Retinoic acid participates in the synthesis of :

Richest source of Vitamin D is :

Retinal is reduced to retinol in intestinal mucosa by a specific retinaldehyde  reductase utilising :

The normal serum concentration of 24,25- dihydroxycholecalciferol in ng/ml is :

One manifestation of vitamin A deficiency is :

Fat soluble vitamins are :

β-Carotene, precursor of vitamin A, is
oxidatively cleaved by :

The international unit of vitamin A is
equivalent to the activity caused by :

Retinal is a component of :

An important function of vitamin A is :

On exposure to light rhodopsin forms :

Preformed Vitamin A is supplied by

The normal serum concentration of 1,25- dihydroxycholecalciferol in pg/ml is :

Vitamin D absorption is increased in:

Vitamins are :

Vitamin A or retinal is a :

Retinol is transported in blood bound to :

The normal serum concentration of 25-hydroxycholecalciferol in ng/ml is :

Carr-Price reaction is used to detect :

The most potent Vitamin D metabolite is :