From agricultural farmers
DNA is a long molecule that consists of two strands of nucleotides twisted together in a long spiral called a double helix<span>. 1. Each </span>nucleotide<span> contains a sugar, a phosphate, and one of the four </span>bases<span>: (A = adenine, ___ = cytosine, ___ = guanine, or ___ = thymine). </span>2<span>.</span>
For veterinarians, the use of DNA technology is to diagnose,
prevent and treat diseases in animals.
Genetic engineering is also used when a certain animal produce a transgenic
animals and breeds from different species for therapeutic proteins, also called
as xenografting.
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The three domain system is wrong and will be corrected.
<u>Explanation:</u>
Carl Woes in 1977 classified the living beings into three domains: Archaea, Bacteria and Eukaryotas based on the 16s rRNA. But now with the advancement of technologies this classification has become a topic of debate and may need revision.
As Meta-genomics was introduced sequencing of DNA has become easy and it's easier now to analyze the chromosomes of an organism. Various new viruses and bacteria have been discovered (such as mimivirus) which do not fit into the classification system (requires the addition of new domains)..
Also, three domains of life is controversial as some scientists believe that Eukaryota evolved from the merge of prokaryotes and archaea (endosymbiosis). So, metagenomics and phylogenomics are revealing the diversity of organisms which are required to be placed in a true domain.
<u>For more information you can read these papers:</u>
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4008548/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5604501/
