Question

Sexual reproduction promotes genetic variation. One way variation occurs is via the production of gametes during meiosis. Sexual organisms are the product of sperm and egg, receiving chromosomes from both parents. But what mechanisms are at work during meiosis to promote genetic variation? Review the prompt and select all that apply.

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Answer 1

Meiosis promotes genetic variation through processes such as crossing-over, independent assortment, and random fertilization, resulting in offspring with unique genetic combinations.

Step-by-step explanation:

During meiosis, several mechanisms contribute to the promotion of genetic variation in sexually reproducing organisms. Three main processes can be highlighted:

• Crossing-over happens during prophase I, where segments of DNA are swapped between homologous chromosomes, leading to a mix of parental traits in the offspring.
• Independent assortment of chromosomes during metaphase I ensures that each gamete gets a random mix of maternal and paternal chromosomes, contributing to unique genetic combinations.
• Random fertilization further shuffles the genetic deck when one sperm out of millions fertilizes an egg, each with different genetic backgrounds.

Together, these processes yield offspring with a genetic makeup that is a unique combination of both parents, accounting for the evolutionary success of sexual reproduction among eukaryotic organisms.

Answer 2

Answer: A, D,E

Explanation: A, D, E Crossing over - homologous chromosomes pair up with their non-identical twins and exchange regions of DNA. Random segregation - The distribution of chromosomes among four gametes. Independent assortment - The homologous chromosomes of a pair must go into separate gametes.