Final answer:
Cells must divide to support growth and repair, and creating identical daughter cells is crucial for maintaining genetic continuity. Chromosomes, which consist of genetic material, are duplicated during cell division to ensure both daughter cells carry the same genetic information. Chromosomes can be counted during cell division when they become visible under a microscope.
Step-by-step explanation:
Why New Cells Are Needed and the Importance of Identical Daughter Cells
Cells are fundamental to life and their replication is crucial for several reasons. Primarily, cells need to divide for growth and repair. For instance, our skin and gastrointestinal lining are areas where cells divide rapidly due to continuous wear and tear. Moreover, it's essential to make identical daughter cells to ensure genetic continuity; that is, every new cell must have the same DNA as its parent cell for the organism to function correctly. This is achieved during cell division, particularly through a process called mitosis, where replicated DNA is equally distributed to each daughter cell.
Chromosomes and Their Counting
Chromosomes are the carriers of genetic information within our cells. Each parent contributes 23 chromosomes, making the typical human cell contain 46 chromosomes. When a cell is ready to divide, DNA replication causes each chromosome to duplicate, creating pairs that then separate during mitosis to ensure both new daughter cells receive a complete set of genetic data. Chromosomes can often be counted during cell division under a microscope, where they are visibly condensed and easiest to distinguish.