In this chapter, we will look at some of the techniques and areas of study so that you can make better decisions.
Discuss how the PCR may be used to analyze DNA.
Natural biological systems can be used to create a product or achieve other goals.
Genetic engineering allows scientists to modify the genomes of a variety of organisms, frombacteria to plants and animals, to either improve the characteristics of the organisms or make biotechnology products.
The research has allowed for the development of new techniques.
Scientists can use these techniques to clone genes and directly edit the genomes of organisms.
A is a person whose genome has been changed using a technology.
A is an example of a genetically modified animal that has had a gene from another animal inserted into it.
We need to look at some of the techniques that are used in the field of genetics before we look at genetically modified organisms.
cloning is the production of genetically identical copies of DNA, cells, or organisms through asexual means Plants are clones of one another when an underground stem or root sends up new shoots.
The members of a colony on a petri dish are clones because they all came from the same cell.
Twins are considered clones.
Each cell in an embryo becomes a complete individual.
Some of the different ways that the term cloning may be used in biology are explored in the Nature of Science feature.
They might want to know the difference between a normal and a mutated gene.
They could use the genes to modify organisms in a beneficial way.
rDNA will be introduced into a host cell.
A plasmid is a common one.
The ring is not part of the main chromosome and can be easily removed from a cell.
A human gene is being cloned.
The basic steps in the cloning of a humangene are shown in this figure.
Human and plasmid DNA are cleaved using a specific type of restriction enzyme.
There is a chance that the human DNA contains the insulin gene.
After a bacterium takes up the plasmid, genes can be cloned.
The product may be retrieved if the gene functions normally.
Two enzymes are needed to introduce foreign DNA into the sample.
Any viral DNA that enters the cell is cut up by hundreds of restriction enzymes that occur naturally inbacteria.
Scientists take advantage of the enzymes and use them to cut any piece of DNA at a specific site.
A piece of foreign DNA can be placed if its ends are close to those exposed by the restriction enzyme.
The "sticky ends" of the two DNA molecules can bind a piece of foreign DNA.
If both are cleaved by the same restriction enzyme, sticky ends can be used to insert foreign DNA.
There are specificlocations where the restriction enzymes cut the DNA.
Each restriction is capable of recognizing a specific sequence of nucleotides.
The "sticky ends" may be useful in the cloning of DNA.
The foreign piece of DNA is sealed with the DNA ligase.
The rDNA molecule has been prepared.
Once treated to make their cells more permeable, they may take up plasmids.
As the plasmid replicates, DNA is cloned.
It is a procedure used to determine the order of the nucleotides in a segment of the genome.
The foundation for the study of forensic biology and our understanding of our evolutionary history can be found in the information from DNA sequencing.
In the early 1970s, this technique was performed manually using dye-terminator substances or radioactive tracer elements attached to each of the four nucleotides during DNA replication, then deciphering the results from a pattern on a gel plate.
Modern-day sequencing involves attaching dyes to the nucleotides and detecting the different dyes via a laser in an automated segment are made, or replicated, using a procedure called the polymerase chain reaction.
A sequence of genes.
Researchers can determine the sequence of a segment of DNA using fluorescent dyes.
The development of the American biochemist Kary Mullis, who was awarded the 1993 Nobel Prize in Chemistry for his discovery, was one of the major changes in the field of molecular biology.
The pace of genetic engineering can be accelerated by the creation of many clones of a piece of DNA.
The process mimics DNA replication in the cell, except that it only makes copies of a targeted sequence.
There is a supply of nucleotides for the new DNA strands and a requirement for the use of DNA polymerase.