The embryo is formed from ........ .

The root cap is covered by an undifferentiated sheath called $P$,and the shoot apex is enclosed in a hollow foliar structure called $Q$.
$\quad\quad\quad P \quad \quad Q$

The apical cell of the $2$-celled pro-embryo in angiosperms undergoes . . . . . . division to form $8$-celled octant pro-embryo.

In angiosperms,the embryo is developed at . . . . . . of the embryo sac.

The tips of the radicle are formed with the help of which cells in a developing embryo?

Scutellum is a