What is mitosis primarily responsible for?

Mitosis is a fundamental process in the cell cycle where a single cell divides to produce two genetically identical daughter cells. This process is crucial for growth, development, and repair in multicellular organisms. The primary responsibility of mitosis is the division of body cells, which allows organisms to grow, replace damaged cells, and maintain tissue health. Through mitosis, each daughter cell receives a complete set of chromosomes, preserving genetic continuity across generations of cells.

In contrast, the other choices focus on different biological functions: energy production, cell respiration, and photosynthesis are not related to the process of cell division. Energy production typically occurs in cellular respiration, which involves breaking down glucose molecules, while photosynthesis is a process in plants that converts light energy into chemical energy. Mitosis, therefore, specifically addresses the mechanism of cellular reproduction and regeneration rather than these metabolic processes.