It depends on what kind of plant it is. Some need light, but some don't need a lot. But if they don't have light, then they won't be able to make food, so they won't be able to grow. Because the electromagnetic energy (the sun) turns into chemical energy (the plant growing).
they begin to die, for example if you dont get enough air what will happen to you?
you get rabies
you will feel cold and you wont have enough energy
because if we dont i will die lol :)
you die.
You are supposed to assume/expect that nothing happens, or the norm happens. E.g. if you are testing if plants grow more in light, you assume they dont, then see if that expectation is consistent with the result.
you get a range of symptons
they die
the answer is that i dont know you fool
your blood cells will be weak and you will be sick.
some die and some dont it depends
if you dont get enough vitamin A your eyes will start to hurt and poor night vision.