During what phase does crossing-over occur? A. prophase I
B. metaphase I
C. anaphase I
D. telophase I
prophase dahhh
What differences would you see in a population of individuals whose chromosomes experience crossing over frequently with a population made up of individuals whose chromosomes dont?
Genetic variation, is crossing over you can have have a chance to mix genes, in cloning they don't crossover.Meiosis is crossing over, Mitosis is cloning.
The correct answer is A. prophase I.
To understand why crossing-over occurs during prophase I, let's break down the process of meiosis, the type of cell division that produces gametes (reproductive cells) in organisms.
During prophase I of meiosis, the homologous chromosomes pair up and form structures called tetrads. Within each tetrad, the chromosomes undergo a process called synapsis, where they physically align themselves next to each other.
It is during this stage that crossing-over occurs. Crossing-over is the exchange of genetic material between homologous chromosomes. Specifically, sections of DNA between nonsister chromatids are swapped, resulting in the exchange of genetic information between the maternal and paternal chromosomes.
Crossing-over is a significant event because it contributes to genetic variation. By shuffling genetic material, it creates new combinations of alleles on chromosomes, which can lead to offspring with different traits.
Therefore, the correct answer is A. prophase I.