NEET2016BotanyCell Cycle and Cell DivisionActual
Match the stages of meiosis of Column-I to their characteristic features in Column-II and select the correct option using the codes given below: Column-I Column–II a. Pachytene (i) The pairing of homologous chromosomes b. Metaphase I (ii) Terminalization of chiasmata c. Diakinesis (iii) Crossing-over takes place d. Zygotene (iv) Chromosomes align at the equatorial plate
Options
- A( array |l|l|l|l| a & b & c & d (iii) & (iv) & (ii) & (i) array )
- B( array |l|l|l|l| a & b & c & d (i) & (iv) & (ii) & (iii) array )
- C( array |l|l|l|l| a & b & c & d (ii) & (iv) & (iii) & (i) array )
- D( array |l|l|l|l| a & b & c & d (iv) & (iii) & (ii) & (i) array )
Correct answer
A. ( array |l|l|l|l| a & b & c & d (iii) & (iv) & (ii) & (i) array )
Step-by-step solution
Zygotene : Chromosomes start pairing together. This process is called synapsis. The paired chromosomes are called homologous chromosomes. The formation of synapsis is accompanied by the formation of the synaptonemal complex. The synaptonemal complex by a pair of homologous chromosomes is called a bivalent or a tetrad. Pachytene: Bivalent chromosomes clearly appear as tetrads, at this stage. Recombination nodules appear. These nodules are the sites at which crossing overtakes place between non-sister chromatids of t