NEET BIOLOGY

Detailed explanation-1: -Interphase is composed of G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth). At the end of interphase comes the mitotic phase, which is made up of mitosis and cytokinesis and leads to the formation of two daughter cells.

Detailed explanation-2: -Initially in G1 phase, the cell grows physically and increases the volume of both protein and organelles. In S phase, the cell copies its DNA to produce two sister chromatids and replicates its nucleosomes. Finally, G2 phase involves further cell growth and organisation of cellular contents.

Detailed explanation-3: -Phases of the Cell Cycle The cell cycle is a 4-stage process consisting of Gap 1 (G1), synthesis (S), Gap 2 (G2), and mitosis (M), which a cell undergoes as it grows and divides. After completing the cycle it either starts the process again from G1 or exits through G0.

Detailed explanation-4: -The correct order of phases of the cell cycle is G1 → S → G2 → M.

Detailed explanation-5: -By studying molecular events in cells, scientists have determined that interphase can be divided into 4 steps: Gap 0 (G0), Gap 1 (G1), S (synthesis) phase, Gap 2 (G2). Cyclin D is the first cyclin produced in the cell cycle, in response to extracellular signals (e.g. growth factors).