Which agent is responsible for pollination in $Cycas$?

When is the endosperm formed in gymnosperms?

$Ephedrine$ is obtained from..........

Which one constitutes the dominant vegetation in colder regions?

Consider the following statements regarding gymnosperms and choose the correct option.
$I.$ In gymnosperms,the male and female gametophytes have an independent existence.
$II.$ The multicellular female gametophyte is retained within the megasporangium.
$III.$ The gymnosperms are heterosporous.
Of these statements:

The phloem of gymnosperms and angiosperms differs due to the presence or absence of . . . . . . .