Hi wii man, Good to see you back!
With the coconut, its the whole thing that is the seed, it actually holds the world record for the largest seed (coco de mer) or the double coconut!
You may have seen these plants on sale in garden centres and even super markets these days. they have huge spear shaped leaves which is the seed leaf, they can be grown indoors for a few years, when they get too big you can donate them to your local Chinese take-away. Good Luck Tbird+