The plant hormone that promotes the formation of abscission layers and fruit ripening is: MCQ with Answer and Explanation

Explanation:
In the S (synthesis) phase of interphase, DNA is replicated. G2 is preparation for mitosis. Interphase is the longest. Cytokinesis follows telophase.

Explanation:
Chlorophyll, the primary photosynthetic pigment, is embedded in the thylakoid membranes within chloroplasts. These membranes contain photosystems I and II, where light-dependent reactions occur. The stroma of the chloroplast houses the Calvin cycle enzymes. Chlorophyll absorbs mainly blue and red light, reflecting green, giving leaves their color.

Explanation:
CFCs, used in refrigerants and aerosol propellants, release chlorine atoms when exposed to UV radiation in the stratosphere. A single chlorine atom can destroy thousands of ozone (O₃) molecules. This led to the formation of the 'ozone hole' over Antarctica. The Montreal Protocol (1987) successfully phased out CFCs, allowing the ozone layer to slowly recover.