define gymnosperms and give two examples of it
Gymnosperms are sporophyte, evergreen, perennial, seed-producing woody plants which may be monoecious or dioecious.
Examples: Cycas, Pinus
Differentiate between Cycas and Pinus.
Cycas | Pinus |
Dioecious i.e. male and female cone in different plant. | Monoecious i.e. male and female cone on same plant. |
Root is dimorphic with tap root and coralloid root. | Root is dimorphic with tap root and mycorhizal root. |
Microsporangium is grouped to form sori. | Sori is absent. |
Pollen tube act as haustorium as male gamete is motile. | Pollen tube act as pollen carrier as male gamete is non motile. |
Dehiscence of pollen grain occurs by pollen drop mechanism. | Dehiscence of pollen grains occurs by sulphur shower mechanism. |