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.
Ripe mango. It should be noted that there are certain variety of mangoes (I've forgotten which particular species) remain green, even when ripe. Therefore, color is not always a tell-all indicator. The press and smell test typically is, if you don't know what type of mango you're buying.