haha.. not mocking you but if you did do reading then you should know what flowering is.
Ok, so vegging is when the plant grows fan leaves and just gets taller and bushier but doesn't produce bud. Usually the veg light cycle is 24/0, 20/4, 18/6 sometimes 16/8 (ex. 24 hours lights on and 0 hours lights off). Flowering is when the plant starts to produce flowers or bud. Its nearing the end of its life cycle and produces the bud to make seeds for offspring and these buds as everyone knows are the amazing gifts of god that we smoke
. Flowering light cycle is generally 12/12
but yeah, if youre in veg then you have a nitogen deficiency but in flowering when the plant is trying to produce buds, it kills off the lower fan leaves and they'll turn yellow and eventually die