Match List I and List II, and select the correct answer.
Only 1 is correct as the crossing over occurs in PROPHASE I stage of meiosis. Hence, Option D.
Which of the following is the correct sequence for a meiotic cell cycle?
S → G1 → G2 → M → S
G1 → S → G2 → M → G1
G2 → G1 → S → M → G2
G1 → G2 → S → M → G2
The regular sequence of G1, S, G2 (interphase) and M (mitotic) phase is called the cell cycle. A cell undergoing meiosis will first enter the G1 phase, followed by the S phase, then G2 phase and finally undergo meiosis. The cells which divide further re-enter the G1 phase and the cycle continues. The cells which do not divide do not proceed beyond the G1 phase but start differentiating by entering the G0 phase.
Crossing over may result in
Cross-like configurations when non-sister chromatids of a bivalent come in contact during the first meiotic division are
Chiasmata is the point of contact, the physical link, between two (non-sister) chromatids belonging to homologous chromosomes. At a given chiasma, an exchange of genetic material can occur between both chromatids, what is called a chromosomal crossover, but this is much more frequent during meiosis than mitosis.
Synapsis occurs in which of the following stages of meiosis?
Synapsis (also called syndesis) is the pairing of two homologous chromosomes that occurs during meiosis. It allows matching-up of homologous pairs prior to their segregation, and possible chromosomal crossover between them. Synapsis takes place during zygotene of Prophase I of Meiosis I. During zygotene stage, synapsis begins with a synaptonemal complex forming between homologous chromosomes. Homologous chromosomes pair up through the process of synapsis to form bivalents.
When synapsis is complete all along the chromosome, the cell is said to have entered a stage called
Synaptonemal complex is observed during cell division in
The formation of tetrad is a special characteristic of Prophase 1 of meiosis 1.
The homologous pair aligns with each other and gets ready for crossing over.
So, the correct option is 'Meiotic Prophase'.
During meiosis, crossover occurs between
Crossover is the exchange of genetic material that occurs between two homologous chromosomes (a set of one maternal and one paternal chromosome that pair up with each other inside a cell during meiosis) non-sister chromatids that results in recombinant chromosomes during sexual reproduction.
Meiosis results in
In meiosis, the daughter cells are not similar to the parent because of
In meiosis, daughter cells are different from parent cell due to the process of crossing over. Crossing over occurs between homologous chromosomes and chromosomal segments are exchanged between homologous chromosomes during crossing over which is the main cause of variation.
So, the correct answer is option A.