What is the function of the centromere in a chromosome?

The centromere plays a crucial role in the structure and function of chromosomes during cell division. Specifically, it serves as the joining point for replicated chromatids. When a chromosome is replicated during the S phase of the cell cycle, it consists of two identical sister chromatids. The centromere is the region where these two chromatids are tightly attached to each other. This attachment is vital for the proper segregation of chromosomes during mitosis and meiosis.

During cell division, the centromere is recognized by the spindle fibers, which are part of the apparatus that pulls the chromatids apart. The fibrous proteins and structures at the centromere allow for the attachment of these spindle fibers, ensuring that each daughter cell receives the correct number of chromosomes. This function is essential for maintaining genetic stability across generations of cells. Thus, the centromere is central to both the structural integrity of the chromosome and its correct distribution to daughter cells during cell division.