Question

Which of the following statements regarding: crossing-over is incorrect?
A. Crossing-over disrupts the linkage between genes on the same chromosome.
B. Crossing-over disrupts the linkage between genes on different chromosomes.
C. Crossing-over produces new genetic combinations.
D. Crossing-over produces non-parental chromosomes.

Answer 1

Hint: Crossing across results in changes. It is a crucial stage in the prophase of meiotic cell division. Genetic material is exchanged as a result. There is a crossing over between two chromatids that are not sisters. Crossing over results in recombination.

Complete Step by Step Answer:
Meiosis, a unique form of cell division, typically takes place in gamete cells. Haploid Zygote production is accomplished through reduction division. This indicates that the number of chromosomes in the subsequent daughter cells is reduced to half that of the original set. When these haploid chromosomes from two separate parents combine to form a zygote, a normal set of chromosomes is once again restored. The zygote that emerges exhibits variances in its phenotypic traits. Crossing over is to blame for this.
Crossing over takes place during the pachytene of the prophase of meiosis and is a crucial step. A pair of homologous chromosomes are involved. The chromosomes have four chromatids at this point. Sister chromatids are chromatids that are part of one chromosome. Non-sister chromatids are those that are located separately on a different chromosome that is a homologous chromosome. These chromatid strands that are not sisters cross each other. Genetic material is transferred from one chromatid to another during crossing over. This alters the genetic composition of the gametes that arise. Gametes are now distinct from the parents who are carrying them. The recombination of genetic material is another name for this. As a result of the mixing of two diverse genetic makeups, when gametes from two separate parents fuse, they generate additional variants.
Therefore, the answer is B. Crossing-over disrupts the linkage between genes on different chromosomes.






Note: Linked genes are split apart by crossing across. The frequency of crossing over ranges from 0 to 50%, however it might be higher than 50%. Additionally, crossing over ensures that both parental and recombinant types will exist in equal amounts in a test cross.