Choose the odd one with respect to the flowering and fruiting pattern.

The terms $Xenia$ and $Metaxenia$ are related to:

Study the following statements.
$I$. Pollen grains of many species cause severe allergies and bronchial afflictions in some people,often leading to chronic respiratory disorders.
$II$. Pollen grains are rich in nutrients.
$III$. Carrot grass came into India as a contaminant with imported wheat.

The male and female reproductive organs of several pteridophytes and gymnosperms are comparable to floral structures of angiosperms. Make an attempt to compare the various reproductive parts of pteridophytes and gymnosperms with reproductive structures of angiosperms.

The zygote develops into an embryo through $.......$ and the primary endosperm cell develops into endosperm tissue through $.......$.

Synergids are helpful in . . . . . . .