Question

How does crossing over increase variation in a population?

Answer 1

Crossing over during meiosis, along with independent assortment and random fertilization, greatly increases genetic variation by creating recombinant chromosomes with unique combinations of maternal and paternal genes.

Step-by-step explanation:

How Crossing Over Increases Variation in a Population

Crossing over is a crucial mechanism in sexual reproduction that contributes to the genetic variation within a population. It occurs during prophase I of meiosis, when homologous chromosomes pair up and exchange parts of their DNA. This process results in recombinant chromosomes, which have a mix of maternal and paternal genes. Independent assortment and random fertilization also play significant roles in increasing genetic diversity. In independent assortment, the way chromosomes line up during meiosis is random, leading to different possible combinations of chromosomes in the gametes. During random fertilization, any sperm can fertilize any egg, further contributing to the variation in offspring.

Mutations can likewise introduce new genes into a population, but crossing over specifically leads to unique combinations of existing genes. Each genetic recombination event during crossing over contributes to the diversity of gene combinations in the haploid gamete cell, which will eventually combine with another gamete to form a genetically unique offspring.

In summary, crossing over, independent assortment, and random fertilization all increase the potential for genetic variation, making it possible for a single human couple to produce more than 64 trillion genetically unique children.

Answer 2

Crossing over or the recombination, is the process, which involve the exchange of chromosomal segment between the non-sister chromatids in the meosis.

It creates a new combination of genes in the gametes, which are not found in the parents and contribute to the genetic diversity of the population.

Due the this the chance of survival of the offspring increases under diverse environment.