Final answer:
The central element of the synaptonemal complex is made up of synaptonemal proteins, which facilitate the pairing of homologous chromosomes during prophase I of meiosis.
Step-by-step explanation:
In the process of meiosis, specifically during prophase I, homologous chromosomes are held together by a structure known as the synaptonemal complex. This complex facilitates the alignment and pairing (synapsis) of homologous chromosomes. The central element of the synaptonemal complex is made up of a group of proteins commonly referred to as synaptonemal proteins. These proteins are distinct from RecA, which is a bacterial protein with homologs involved in DNA repair and synapsis across different species, and cohesin proteins, which assist in the cohesion of the chromatids at the centromere. The central element is important as it not only aligns the chromosomes but also supports the process of crossing over or genetic recombination through structures called recombination nodules located along the complex.