Write brief note on the following: (a) Synaptonemal complex. (b) Metaphase plate.

Explanation

(a) Synaptonemal complex. It is an electron microscopic ladder like filamentous complex of nucleoproteins. Itis formed between the homologous chromosomes during zygotene and helps in their synapsis. It extends upto pachytene and starts disappearing after crossing over and helps in desynapsis of homologous chromosomes.
(ii)Metaphase plate . The plate aligment of chromosomes at the equator of spindle during metaphase of cell division is called metaphase plate . In mitosis chromosomes arranged at equator in one metaphase plate while in meiosis bivalents arranged at equator in two metaphase plates .