Question

What accompanies chromosomal synapsis in the zygotene phase of prophase?

Answer 1

Synapsis:

1. The pairing of 2 homologous chromosomes which occurs during meiosis is called synapsis (also called syndesis).
2. It also enables matching of the homologous pairs and possible chromosomal crossover between them prior to their own segregation.
3. This process is said to be occurring during prophase I of meiosis.
4. Their ends are first attached to the nuclear envelope once the homologous chromosomes synapse.
5. Then, aided by the extranuclear cytoskeleton, such end-membrane complexes migrate until matching ends have been paired.
6. Then chromosome's intervening regions are said to be brought together and connected by a protein-RNA complex and referred to as the synaptonemal complex.
7. During meiosis, the autosomes undergo synapsis & are kept together by a protein complex called the synaptonemal complex along the entire length of chromosomes.
8. Sex chromosomes also often undergo synapsis, but only one end of each sex chromosome contains a synaptonemal protein complex which generally binds homologous chromosomes together.