Abscission layer is the layer of cutinized parenchyma cells that develops in the abscission zone. The abscission zone form across the base of the plant part, where the break eventually occurs. During the photosyntesis chlorophyll using sunlight produces sugar and storches which are used as food by plant. And sugar accumulate in leaves.
For air masses to form fronts, they must collide with each other. B.
The answer is 4Fe+3O2→2Fe2O3
