In the absence of lactose, the repressor protein encoded by the I gene binds to the lac operator and prevents transcription. Binding of allolactose to the repressor causes it to leave the operator. This enables RNA polymerase to transcribe the three genes of the operon.
A tough-skinned tropical fruit, the mango features a sweet, orange- to red-color flesh inside when ripe. Kensington pride, Kent, Palmer and sensation are only a few of the many varieties of mango available through groceries and markets.
Mango develops small, white or pink flowers that consist of 5 petals. Individual flowers are part of branched inflorescence. Flowers of mango are pollinated by wind or by insects such as different types of flies, moths and butterflies. Mango develops egg- or kidney-shaped fruit covered with smooth skin. Size of the fruit and color of the skin depends on the variety. Most commercially available mango varieties have reddish-green skin. Edible part of the fruit consists of orange flesh that surrounds large seed, located centrally. Mango tree starts to produce fruit after four years.