The size of animal and plant increases by:

🧠 Explanation:

Growth involves the division and enlargement of cells, allowing organisms to develop from smaller forms into mature sizes. In plants, growth occurs mainly in specific regions called meristems, where new cells are produced continuously. Animals grow by cell division and differentiation, leading to an increase in body size and complexity. This biological process is regulated by genetic factors, nutrition, and environmental conditions. Growth enables living organisms to reach their full functional capabilities, reproduce, and adapt to their surroundings throughout their life cycles.