Which is the source of turpentine oil?

What type of habitat characteristics do $Gymnosperms$ exhibit?

Select one of the following pairs of important features distinguishing $Gnetum$ from $Cycas$ and $Pinus$ and showing affinities with angiosperms.

Male gametes of cycads are

Which one of the following is the characteristic feature of gymnosperms?

The roots of $Sequoia$ are generally...