What does it generally indicate when a "Lucky Bamboo" plant turns
yellow on some parts (the top of a stem); it srated developing this
color change when I put it outside, but no in direct sunlight.

About tropical plants in general: When there are a few leaves (of
many) that seem to be turning yellow (I live in Florida), does this
indicate too much water or too much sun? The other day, this same leaf
was normal. It was recently transplanted into a larger pot.

Thanks,
Mark