Question

Variegated coloration of leaves, first studied by K.Correns in 1909 is inherited only from the female parent. The genes coding for this trait are located in

• A. ER
• B. Nucleus
• C. Plastids
• D. Plasma membrane

Answer 1

The correct option is C Plastids

Total absence of plastid pigments causes a sector of a leaf or stem to have white patches. This condition is termed as variegation (Metrosideros). Variegation is produced when there is a cell mutation (cytological chimera), and all cells produced from that mutant mother cell lack the pigments, either because plastids are not present or the plastid cannot complete the manufacture of the pigment apparatus. White, therefore, is where colour is missing. The zones where chloroplasts are not present are zones where no photosynthesis will occur, hence a variegated leaf has a lowered potential to fix carbon dioxide into sugars, and as a consequence, a variegated plant also tends to grow more slowly. Variegated leaves occur rarely in nature but are extremely common among indoor and outdoor ornamentals, where they have been saved as horticultural oddities.