(10pts.) why are angiosperms willing to give up pollen or nectar to insects?

Many flowers use colors to attract insects, sometimes helped by colored guiding marks. Some have ultraviolet marks that can be seen by insects but are invisible to human eyes. Flowers are often shaped to provide a landing platform for visiting insects or to force them to brush against anthers and stigmas. It only has very small petals but big bright red clusters of stamens.