Persistent nucellus in the seed is known as

Choose correct sentence.

$(I)$ Nucleus of the functional megaspore divides meiotically to form two nuclei.

$(II)$ After $8$ nucleate stage, cell walls are laid down leading to organization of typical female gametophyte

$(III)$ The egg apparatus, consists of two synergids and one egg cell.

$(IV)$ Three cells are at the chalaza end are called antipodal cells.

If diploid chromosome number in a flowering plant is $12$, then which one of the following will have only $6$ chromosomes

Megaspores are produced from the megaspore mother cells after

The ovule in which the funicle, chalaza and micropyle lie in one vertical plane, is called