Explain why a topographic map has a key.

The reason would be to make it easier to understand. if it did not have a key how would people know what the symbols meant?

Exocytosis occurs when a vesicle is produced by the Golgi bodies that completely encloses a particle inside the cell. The particle-laden vesicle moves to the plasma membrane, fuses with it, then expels its contents outside the cell.

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ha e a great day.