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A normal chromosome and its homolog carrying an inversion are given. The dot (•) represents the centromere.Normal: A B C • D E F G H I JInversion: a b c • d g f e h i jWhat type of inversion is present and what is the name of the structure that will form during synapsis?

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Answer:

Paracentric Inversion

Step-by-step explanation:

Some of the mutations that occur in chromosomes involve inversions. These imply a structural change that affect the genes´ order in the chromosome.

In the inversion, the chromosome suffers two ruptures, and then it is reconstituted. The problem is that this reconstitution occurs inverted. These two ruptures might occur in the same chromosomic arm, or it might involve the centromere. The first case is known as paracentric inversion while the second case is called pericentric inversion. Note: The exposed example is a product of paracentric inversion, as the centromere is located between C and D genes, and the inversion involves E, F, and G genes.

During meiosis, when homologous chromosomes mate, and a structure known as inversion loop is formed. The chiasms within them make a place to inviable gametes. The crossover event inside the loop produces create a bridge between the two homologous chromosomes, and the fragment without centromemer is lost. After that, the bride breaks, and the two homologous chromosomes segregates. The final result is two viable gametes identical to the ones of the progenitors, and two inviable gametes, result of inversion.

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