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By the end of this section, you will be able to:
  • Explain the basic techniques used to manipulate genetic material
  • Explain molecular and reproductive cloning

Biotechnology is the use of artificial methods to modify the genetic material of living organisms or cells to produce novel compounds or to perform new functions. Biotechnology has been used for improving livestock and crops since the beginning of agriculture through selective breeding. Since the discovery of the structure of DNA in 1953, and particularly since the development of tools and methods to manipulate DNA in the 1970s, biotechnology has become synonymous with the manipulation of organisms’ DNA at the molecular level. The primary applications of this technology are in medicine (for the production of vaccines and antibiotics) and in agriculture (for the genetic modification of crops). Biotechnology also has many industrial applications, such as fermentation, the treatment of oil spills, and the production of biofuels, as well as many household applications such as the use of enzymes in laundry detergent.

Manipulating genetic material

To accomplish the applications described above, biotechnologists must be able to extract, manipulate, and analyze nucleic acids.

Review of nucleic acid structure

To understand the basic techniques used to work with nucleic acids, remember that nucleic acids are macromolecules made of nucleotides (a sugar, a phosphate, and a nitrogenous base). The phosphate groups on these molecules each have a net negative charge. An entire set of DNA molecules in the nucleus of eukaryotic organisms is called the genome. DNA has two complementary strands linked by hydrogen bonds between the paired bases.

Unlike DNA in eukaryotic cells, RNA molecules leave the nucleus. Messenger RNA (mRNA) is analyzed most frequently because it represents the protein-coding genes that are being expressed in the cell.

Isolation of nucleic acids

To study or manipulate nucleic acids, the DNA must first be extracted from cells. Various techniques are used to extract different types of DNA ( [link] ). Most nucleic acid extraction techniques involve steps to break open the cell, and then the use of enzymatic reactions to destroy all undesired macromolecules. Cells are broken open using a detergent solution containing buffering compounds. To prevent degradation and contamination, macromolecules such as proteins and RNA are inactivated using enzymes. The DNA is then brought out of solution using alcohol. The resulting DNA, because it is made up of long polymers, forms a gelatinous mass.

Four test tubes are illustrated, showing four steps in extracting DNA. In the first, cells are lysed using a detergent that disrupts the plasma membrane. In the second, cell contents are treated with protease to destroy protein, and RNase to destroy RNA. In the third, cell debris is pelleted in a centrifuge. The supernatant (liquid) containing the DNA is transferred to a clean tube. In the fourth test tube, the DNA is precipitated with ethanol. It forms viscous strands that can be spooled on a glass rod.
This diagram shows the basic method used for the extraction of DNA.

RNA is studied to understand gene expression patterns in cells. RNA is naturally very unstable because enzymes that break down RNA are commonly present in nature. Some are even secreted by our own skin and are very difficult to inactivate. Similar to DNA extraction, RNA extraction involves the use of various buffers and enzymes to inactivate other macromolecules and preserve only the RNA.

Questions & Answers

what makes golgi body in plants
Abdulkareem Reply
name the membrane of the plants
During organs transplantation, the organs cannot be taken from just anybody since the graft would be rejected sooner or later due to
Liter Reply
Non-MHC compatibility on the organ and an attack from the patient's immune system.
what makes golgi body in plants
what is integument system
Joy Reply
Cellular respiration
Lucy Reply
what are the characteristics of living things
Ruth Reply
Movement Respiration Nutrition/Feeding Irritability/Sensitivity Growth Excretion Reproduction Deat/Life span
What makes children from the same father and mother sometimes don't look alike?
identification of problems
Nana Reply
what happens in the process of raising the human arms
what is biology
Brandi Reply
first step in scientific method
In an investigation the pancreatic duct of a mammal was blocked.It was found that the blood sugar regulation remained normal while food digestion was impaired.Explain
Mac Reply
To begin with, obstruction of pancreatic duct will alter the blood sugar level as the juices responsible for glucose regulation will be rendered inconsequential. This will in turn affect the rate of digestion and absorbtion of digested food substances by the Villus .
characteristics of algae
Algae are eukaryotic organisms. Algae do not have roots and stems. Algae have chlorophyll and helps in carrying out photosynthesis.
Cell wall is the rigid layer enclosed by membranes of plants and prokayortic cell, it maintains the shape of the cell and serve as a protective barrier.
chizoba Reply
ECOLOGY: is a branch of biology that studies the interactions among organisms and their biophysical environment, which includes both biotic and abiotic components. 
via nutrient cycles and energy flows. For instance, the energy from the sun is captured by plants through photosynthesis. Photosynthesis is a biological process through which plants manufacture their own food with the aid of light from the sun and frc sources (e.g. cabon dioxide and water)
What is cell wall
Taiwo Reply
cell wall is the outemost rigid covering of the plants ,that provides protection to the plants.
what is integument system
The integument system is your skin and the largest system in the body.
what is protoplast?
The cytoplasm is inside of the cell, minus the nucleus. The protoplasm is the inside of the cell and the nucleus.
Out line of cell
what is ecology, ecosystem?
Nkeng Reply
what is digestive system
Lucky Reply
digestive system is the human syman system that icludes esopuges stomach o braking down of food in to useful substance to our body
definition of biology basics
Ritu Reply
the potential energy of a molecule can be inquired by their number of?
Jesus Reply
note on the structure of DNA
The chemical potential of a species in a mixture is defined as the rate of change of free energy of a thermodynamic system with respect to the change in the number of atoms or molecules of the species that are added to the system. 

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Source:  OpenStax, Concepts of biology. OpenStax CNX. Feb 29, 2016 Download for free at http://cnx.org/content/col11487/1.9
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