Recombination occurs when two molecules of DNA exchange pieces of their genetic material with each other. One of the most notable examples of recombination takes place during meiosis (specifically, during prophase I), when homologous chromosomes line up in pairs and swap segments of DNA.
What is the exchange of chromosome segments between homologous chromosomes?
The tight pairing of the homologous chromosomes is called synapsis. In synapsis, the genes on the chromatids of the homologous chromosomes are precisely aligned with each other. An exchange of chromosome segments between non-sister homologous chromatids occurs and is called crossing over.
What involves a physical exchange of DNA segments between homologous chromosomes multiple choice question?
Crossing over occurs between prophase I and metaphase I and is the process where two homologous non-sister chromatids pair up with each other and exchange different segments of genetic material to form two recombinant chromosome sister chromatids.
What is the process by which homologous chromosomes exchange segments of DNA?
Explanation: During prophase I, homologous chromosomes pair with each other and exchange genetic material in a process called chromosomal crossover. The exchange occurs in segments over a small region of homology (similarity in sequence, ie., the same alleles).
Is the exchange of DNA between homologous chromosomes?
Recombination is the exchange of genetic material between homologous chromosomes. Recombination is the exchange of genetic material between homologous chromosomes.
What is the physical exchange of DNA segments between maternal and paternal homologous chromosomes?
An exchange of chromosome segments between non-sister homologous chromatids occurs and is called crossing over. … The chromosomes that have a mixture of maternal and paternal sequence are called recombinant and the chromosomes that are completely paternal or maternal are called non-recombinant.
When homologous segments of DNA are exchanged between Nonsister chromatids of a homologous chromosome pair during synapsis <UNK> occurs?
In synapsis, the genes on the chromatids of the homologous chromosomes are aligned precisely with each other (Figure 1). The synaptonemal complex supports the exchange of chromosomal segments between non-sister homologous chromatids, a process called crossing over.
What is the definition of metaphase 1?
Metaphase I is the second stage in meiosis I. … At metaphase I, the homologous chromosomes move to the center of the cell and orient themselves along an equatorial plane, forming the so-called metaphase plate.
During which phase of meiosis do homologous chromosomes exchange segments quizlet?
During which phase of meiosis do homologous chromosomes exchange segments? Exchange of chromosome segments occurs during prophase I (meiosis I).
What is crossing over class 12th?
Crossing over is a process where there is exchange of genetic material or the segments during sexual reproduction between the non-sister chromatids of the homologous chromosomes. … It is one of the final phases of the genetic recombination.
What holds homologous chromosomes together?
1: Synapsis holds pairs of homologous chromosomes together: Early in prophase I, homologous chromosomes come together to form a synapse. The chromosomes are bound tightly together and in perfect alignment by a protein lattice called a synaptonemal complex and by cohesin proteins at the centromere.
What happens during crossing over quizlet?
Crossing over occurs during prophase I of meiosis I. It involves the switching of genes between homologues non-sister chromatids which allows the mixture of maternal and paternal genetic material with new, recombinant chromosomes. … Compare Meiosis II to mitosis.