Spindle-shaped male gametes are found in:

Which organisms died and became coal deposits?

Xylem vessels and phloem companion cells are generally absent in

Independent alternation of generations is found in .......

If a sporangium is derived from a single cell,it is called:

In some of the pteridophytes and gymnosperms,the sporophylls aggregate at the apices of the main stem or its branches to form definite compact structures. These compact structures are called: