Question

In synapsis, two homologous chromosomes are connected at________
A. Centromeres
B. Chromomeres
C. Telomeres
D. None of the above

Answer 1

Synapsis is the pairing process of two homologous chromosomes that occur during meiosis, before segregation, for the formation of chromosomal crossover between them. The synapsis occurs during prophase-I in meiosis-I. The ends of the synapsed chromosome are attached to the nuclear envelope.

Complete answer:

Option B: Chromomeres- The two homologous chromosomes contain the same gene in the same region with their chromosomal arms, such homologous chromosomes are attached to the chromomeres. The chromosomes are protein and RNA complex, which is known as synaptonemal complex also called ribo-nucelo protein. Which hold the two homologous chromosomes end to end region. During synapsis, the homologous chromosome does not appear smooth due to the present of granule, which is local coiling continuous DNA.

Option A: Centromere- The centromere is the DNA sequence, which attached the pair of sister chromatids, at the time of mitosis, the spindle fibre attaches with the centromere through kinetochore. The main function of the centromere is to provide a foundation for the kinetochore assemblage, which is necessary for chromosomal segregation process.

Option C: Telomeres- It is the cap of each end of DNA strand which protects the chromosomes from erosion during the replication process and in each replication process telomeres get shortened due to Okazaki fragment. Telomeres are the repetitive region of the nucleotide sequence. The telomeres protect themselves by a complex protein called shelterin and by RNA, which is decoded by the telomeric DNA (TERRA).

Hence, the correct answer is option (A).

Note: Chromosomes are the genetic material, which is passed on the next generation, through gametes formation and then fertilization. Formation of gametes is complex in the process of cell division, which occurs in the meiosis phase of the cell cycle in which one cell gives rise to two-four daughter cells with a reduced number of chromosomes.