This could make some diseases more dangerous as all the organisms would be affected. Also, there is an increased risk of genetic disease caused by recessive alleles. All the genes and their different alleles within a population is its gene pool.
Inbreeding can lead to the loss of alleles from the gene pool, making it more difficult to produce new varieties in the future. Selective breeding Selective breeding is the traditional method for improving crops and livestock, such as increasing disease resistance or milk yield. In many ways, technology reduces the amount of time we dedicate to basic activities like food production, and makes our lives easier and more enjoyable.
Everyone is familiar with how transportation has changed over time to be more efficient and safer Figure 1. Agriculture has also undergone tremendous changes, many of which have made food and fiber production more efficient and safer Figure 1.
There are negative aspects to having so few members of society involved in agriculture, but this serves to illustrate how technological developments have reduced the need for basic farm labor.
Figure 1: A timeline showing how human transportation systems have evolved. A timeline showing how human transportation systems have evolved, from primitive, slow, and inefficient vehicles, to modern, faster, and more efficient options. Corresponding advances in agricultural biotechnology are shown below, similarly illustrating how advances changed our ability to develop new agricultural crops. Wieczorek and Mark G. All rights reserved. Mutations Figure 2 are changes in the genetic makeup of a plant.
Mutations occur naturally and sometimes result in the development of new beneficial traits. In , plant breeders learned that they could make mutations happen faster with a process called mutagenesis. Radiation or chemicals are used to change the plant's DNA, the basic molecular system of all organisms' genetic material.
The goal is to cause changes in the sequence of the base pairs of DNA, which provide biochemical instructions for the development of plants. Resultant plants may possess new and desirable characteristics through this modification of their genetic material.
During this process, plant breeders must grow and evaluate each plant from each seed produced. Figure 2: The effects of genetic mutations in carrots. Induced mutation breeding was widely used in the United States during the 's, but today few varieties are produced using this technique.
As our understanding of genetics developed, so new technologies for plant variety development arose. Examples of these that are used today include genetic marker assisted breeding, where molecular markers associated with specific traits could be used to direct breeding programs, and genetic engineering. Some of the significant steps leading to the current state of the art are explained below. Many different tools are available for increasing and improving agricultural production.
These tools include methods to develop new varieties such as classical breeding and biotechnology. Traditional agricultural approaches are experiencing some resurgence today, with renewed interest in organic agriculture; an approach that does not embrace the use of genetically engineered crops.
The role that genetic engineering stands to play in sustainable agricultural development is an interesting topic for the future. American Association for the Advancement of Science. Annual meeting Land Grant Universities Can GM crops harm the environment?
McLintock, B. The origin and behavior of mutable loci in maize. Pray, L. Nature Education Knowledge 1 , Thorpe, T. History of plant tissue culture. Molecular Biotechnology 37 , — Watson, J. Recombinant DNA , 2nd ed. New York, NY: W. Opponents believe that GM will damage the clean, green image of New Zealand as well as damage the economy, and there are numerous ethical issues to consider.
What are the environmental risks of GM crops? Is it ethical to exploit animals for human benefit? This article will provide an outline of GM, its uses in medicine and agriculture, and will help explain the issues surrounding the GM debate in New Zealand.
GM provides a way of expressing desirable characteristics in an organism that otherwise would not display them. It is the insertion of a gene into an organism, altering the genetic makeup. This produces a transgenic organism, one that expresses a foreign gene. In animals, a gene is inserted into an embryo, modifying the genome to manufacture the product of this new gene.
In plants, a gene is injected into a single cell that is grown from a seed into a plant. This plant expresses the new gene in all its cells. The difference between GM and selective breeding. Rather, it is the conscious selection for desirable traits. For example, humans have always selected cows with the highest milk yield and bred from these to produce herds with good milk production. A chance mutant grape with no seeds was bred to produce seedless grapes now available in our shops and supermarkets.
Humans have selectively bred apples to create lots of different varieties. Image credit: Shutterstock. A diagram showing the effect of selectively breeding for height in plants. Image credit: Genome Research Limited.
Purebred dogs like the Labrador Retriever were originally established through many generations of inbreeding. Image credit: PetsNerd. The Labradoodle is a crossbred dog resulting from breeding a Labrador with a poodle. GMOs are organisms that have had their characteristics changed through the modification of their DNA.
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