Final answer:
The structure at the tip of a stamen that contains pollen sacs is called the anther.
Step-by-step explanation:
The structure at the tip of a stamen that contains pollen sacs is called the anther. The anther is the part of the stamen that produces and holds the pollen grains. It consists of sac-like structures where meiosis occurs and pollen grains are formed. The anther is supported by a stalk-like filament.