Which of the following is not a characteristic of mitosis?

Polytene chromosomes in salivary glands are formed as a result of:

Match the following:

Column-$I$	Column-$II$
$A$. $G_2$-phase	$1$. First phase of prophase-$I$
$B$. Anaphase	$2$. Proteins are synthesized in preparation for mitosis
$C$. Leptotene	$3$. Terminalisation of chiasmata
$D$. Diakinesis	$4$. Centromeres split and chromatids separate

In which type of cell division does spindle formation not occur?

The following events occur during the various phases of the cell cycle. Name the phase against each of the events.
$(a)$ Disintegration of nuclear membrane .........
$(b)$ Appearance of nucleolus
$(c)$ Division of centromere
$(d)$ Replication of $DNA$

$(1)$ Give scientific reason: Meiosis is called reductional division.
$(2)$ Give scientific reason: Mitosis is necessary for growth,development,and repair of the cell.