by flowers
The flower's sweet nectar attracts bees to pollinate it. Bees gather nectar and make it into honey.
Flowers make nectar and as far as I know it can't be made artificially.
Whenever they can collect nectar. This depends on the weather; air temperature; availability of nectar-bearing flowers and, indeed, whether those flowers have nectar (they won't, for instance, in a drought).
It doesn't. Bees make honey from nectar. Pollen is used to feed the bee larvae.
Yes, they do.
Nectar
Because they don't need animals to polinate. If they make nectar or have bright colours and strong scents, it will be an animal-polinated flower. So they don't need to make nectar or have bright colour
To make honey.
the parts of a flower that make nectar
They have a secrete enzyme in there mouth that when they they collect nectar and mix it with the enzyme it makes honey.
the chloroplasts make food (nectar) in their leaves
All bees collect nectar for their own consumption. Only the honey bee collects sufficient to make enough honey for us to harvest.