1. Describe the processes of synapsis and crossing-over and explain when these processes occur within meiosis....

1. Describe the processes of synapsis and crossing-over and explain when these processes occur within meiosis.

2. Describe how chromosomal variation is an advantage to sexually reproducing organisms.

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Expert Solution

1: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 prophase I of meiosis.

Crossing over is the exchange of genes between two chromosomes, resulting in non-identical chromatids that comprise the genetic material of gametes. This process occurs during Prophase I of Meiosis, just prior to chromosome alignment and splitting of the cell.

2:In many animals, it is actually the only mode of reproduction. The genetic diversity of sexually-produced offspring is thought to give species a better chance of surviving in an unpredictable or changing environment. Scientists recognize some real disadvantages to sexual reproduction.

gladiator answered 1 year ago

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