The filiform apparatus is a characteristic feature of which of the following?

In angiosperms,the female gametophyte is also known as:

The three cells present at the chalazal end form $.....P......$,and the three cells present at the micropylar end form $.....Q.....$.
$\quad\quad\quad \quad \text { P } \quad\quad\quad \text { Q }$

An ovule is equivalent to:

The stalk of the ovule is called

What is the arrangement of nuclei in a typical mature embryo sac of an angiosperm?