Top-shaped multiciliate male gametes, and the mature seed which bears only one embryo with two cotyledons,…
Top-shaped multiciliate male gametes, and the mature seed which bears only one embryo with two cotyledons, are characterised features of:
cycads
conifers
polypetalous angiosperms
gamopetalous angiosperms.
Solution
Cycads are the gymnosperm having largest top shaped multiciliate male gametes. Conifers have sperm that do not have flagella, but instead are conveyed to the egg via a pollen tube. It is important to note that the seeds of gymnosperms are not enclosed in their final state upon the cone.