How to judge whether seeds have endosperm or not

Observe the shape of seeds; Specific gravity of seeds, etc.

Observe the shape of seeds: seeds with endosperm are usually large, full in shape and smooth in surface. But the seeds without endosperm are small and the surface may be rough.

Specific gravity of seeds: the specific gravity of seeds with endosperm is larger, and the specific gravity of seeds without endosperm is smaller. You can test the specific gravity of seeds by floating and sinking method, put the seeds into water and observe their floating and sinking situation.