Homologous chromosomes pair up and exchange segments of DNA.
Option A
<h3><u>Explanation:</u></h3>
Crossing over is an event of Prophase 1 of meiosis 1. It occurs in the zygotene phase of prophase 1. Here the homologous chromosome pairs get very close together and gets packed within protein coat. The enzymes randomly cut the DNA segments from both chromosomes at same loci and exchange them with each other. This results in the exchange of genes between the two chromosomes. This is how the variation comes to place between offsprings of the same individuals. The crossing over results to form X shaped intersections between homologous pair of chromosomes which is called as chaismata. This phase occurs in pachytene phase and is visible in diplotene phase when the protein coat dissolves.
Answer:
Greasy pig disease (Facial dermatitis/exudative epidermitis) Lice. Mange. Ringworm.
It destroys the quality of soil
it kills the useful micro organisms present in the soil
Answer:
1. Confusion
2. Financial issue
Explanation:
1. The reason I say this is that many of them are not really sure about what they want they want to do in their later future making them a little confused on what to do.
2. It is a common issue which has taken away so many bright minds away from their future in helping the world and their individual community to prosper in different ways.
If it is always expressed it is dominant, also dominant allele is a possible answer. If it is not expressed unless both alleles are the same, it is recessive.