G1, S and G2 — DNA replication to 4n, organelle synthesis, growth, and centriole prep for spindle formation.

Chromosomes condense, the nuclear envelope breaks down, centrioles reach the poles, then chromatid pairs align on the equator.

Centromeres split, spindles pull identical chromatids apart, nuclear envelopes reform, and a cell plate partitions plant daughters.

Index = (cells in mitosis ÷ total) × 100; stains make chromosomes and spindles visible so phases can be counted.

Measure, convert units (mm oµm), divide image by actual size, and round to two significant figures.

Crossing over, independent assortment, linked genes, and non-disjunction in anaphase II causing abnormal zygote ploidy.

Tube and generative nuclei, then zygote (2n) plus triploid endosperm (3n) — the dual fusion unique to flowering plants.

DNA methylation silences tumour suppressors like RB; Paclitaxel blocks spindle shortening and slows tumour growth.

Cross vs self-pollination trade-offs, and why mismatched hybrid chromosomes cannot pair in meiosis.