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Homework Help: Science: Biology: Breeding New Organisms
by Leo Galleguillos
During the early 1500s, there were many different Indian tribes including the Palouse and Nez Percé. These two Indian tribes conducted some of the first genetic engineering. They noticed that some of their horses were covered with beautiful skin colors, but at the same time weak and tough to train. They also noticed some of their other horses were strong and easy to train, but were covered with ugly colors.
The Palouse and Nez Percé tried to create a breed of horses that was both colorful and strong. To do this, they bred colorful-weak horses with ugly-strong horses. While half of the results were ugly-weak horses, the other half were colorful-strong. The Palouse and Nez Percé continued to breed only the colorful-strong horses, and the new breed of horses is now called the appaloosa.
The breeding of the appaloosa is a great example of selective breeding. Selective breeding, by definition, is the process in which individual organisms with desired characteristics are chosen to form a new generation. Now only has selective breeding created some of the favorite horses, but has also created the good-looking dogs and cats.
The breeding of the appaloosa is also a great example of hybridization. Hybridization, by definition, is the breeding of organisms with different characteristics.
After selective breeding or hybridization is complete, most scientists conduct inbreeding. Inbreeding, by definition, is the continued breeding of closely related individuals. For example, inbreeding could be conducted on two good-looking poodles to produce more good-looking poodles.
Unfortunately, inbreeding comes with a big set of problems: mutations. A mutation, by definition, is an inheritable change in genetic information. Mutations occur in dogs fairly often. Some dogs are born blind, while others have joint deformities.
There are four different types of mutations. Chromosomal mutations, by definition, are mutations that affect the number or structure of chromosomes in a cell. A gene mutation, by definition, is a mutation that affects only an individual gene. A point mutation, by definition, is a mutation that affects a specific nucleotide of a gene. A frameshift mutation, by definition, is a mutation in which one nucleotide has been added or deleted from the genes nucleotide sequence, resulting in shifting of the nucleotides.
Homework Help: Science: Biology
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