Biology For Class X - Chapter No. 8 - Biotechnology - Question Answers

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CHAPTER 8: BIOTECHNOLOGY
Questions Answers

By Mrs. Ayesha Arif
Vice Principal
(Jauhar Progressive School)
Q.1: Define biotechnology?
Ans: BIOTECHNOLOGY:
Introduction:
The term "Biotechnology" was used before the twentieth century for traditional activities such as making dairy products like cheese and curds, as well as bread, wine, beer, etc. In 1919, a Hungarian agriculture engineer called Karl Ereky coined the word Biotechnology.
Definitions:
There are several definitions for biotechnology.
1. Simple Definition is that:

"It is the commercialization of cell and molecular biology."

2. Classical Or Modern Biotechnology: According to the National Science Academy of United:

"Biotechnology is the controlled use of biological agents like cells or cellular components for beneficial use".

It covers both classical as well as modern biotechnology.

3. General Definition: Generally, biotechnology can be defined as:

"The use of living organisms, cells or cellular components  for the production of compounds or precise genetic improvement of living things for the benefit of man"

Old Biotechnology:
Even though biotechnology has been in practice for thousands of years  but credit goes to Indo Aryan civilizations, which first practised biotechnology in 5000 BC to produced fermented foods, medicines and to keep the environment clean.

Q.2: What is genetic engineering? Write down the role of genetic engineering in biotechnology OR
Why genetic engineering is considered as modern biotechnology. Explain?
Ans: GENETIC ENGINEERING:
Definition:
Genetic engineering is considered as modern biotechnology. It has been defined as:

"The artificial manipulation, modification, and recombination of DNA or other nucleic acid molecules in order to modify an organism or population of organisms. It refers to any process in which an organism’s genome is intentionally altered."

Explanation:
ROLE OF GENETIC ENGINEERING IN BIOTECHNOLOGY:
Genetic engineering play important role in biotechnology. Such as:
1. Cloning:
Genetic engineering does not encompass traditional breeding techniques because it requires manipulation of an organism’s genes through cloning or transformation via the addition of foreign DNA.
For example: a DNA fragment may be isolated from one organism spliced to other DNA fragments, and put into a bacterium or another organism. This process is called cloning because many identical copies can be made of the original DNA fragment.

2. Production Of insulin:
In 1970s, the scientists were able to alter the DNA of the organisms and in 1978 the first genetically engineered drug, human insulin was produced by bacteria.

3. Vitro Mutagenic Methods.
In another example of genetic engineering, a stretch of DNA, often an entire gene, may be isolated and its nucleotide sequence determined, or its nucleotide sequence may be altered by in vitro mutagenic methods.
There are several ways that DNA can be cut, spliced or otherwise altered. But engineered DNA by itself is a static molecule. To be anything more than the end of a laboratory exercise, the molecule must be integrated into a system of production; to have an impact on society at large; it must become a component of an industrial or otherwise useful process.

Basic: Objectives Of Genetic Engineering Activities
 The related activities in genetic engineering have two basic objectives:

1. To learn more about the ways nature works, and
2. To make use of this knowledge for practical purposes.

Benefits Of Fermentation In Genetic Engineering:
A useful genetic approach to increase the efficiency of production. The fermentation was useful in its production and genetic engineering promises to make the fermentation process economically competitive.

Q.3: What is HGP? Write down its objectives?
Ans: HGP Or Human Genome Project:
In 1990, The Human Genome Project was launched to map all the genes of the human cell. The complete draft of the human genome sequence was published in 2002.
OBJECTIVES:
It has following objectives:

• Determining the human DNA sequence.
• Understanding the function of the human genetic code
• Identifying all of the genes.
• Determining their functions Understanding how and when genes are turned on and off throughout the lifetime of an individual.

Q.4: What are the scope and importance of biotechnology?
Ans: Scope and importance of Biotechnology:
Biotechnology is controlled use of biological agents for beneficial use. It is integrated use of biochemistry, molecular biology, microbiology to achieve technological application of the capabilities of biological agents. Therefore, biotechnology has emerged as a science with immense potential for human health to environmental protection.
The following are the areas of the application of biotechnology:

1. Biotechnology in medicine:
In the field of medicine biotechnology has been extremely helpful in the production of large number of vaccines and antibodies. The major achievements include:

• Production of a monoclonal antibody, DNA, RNA probes for diagnosis of various diseases.
• Valuable drugs like insulin and interferon have been synthesized by bacteria for the treatment of human diseases.
• DNA fingerprinting is utilized for identification of parents and criminals.
• Development of recombinant vaccines like human hepatitis B etc. by genetically engineered microbes.
  

2. Biotechnology in Agriculture:
Biotechnology has been beneficial in the field of agriculture in the following ways:

• Plant cell, tissue, and organ culture are used for rapid and economic clonal multiplication of fruit and forest trees.
• They are also used for the production of virus-free genetic stocks and planting material as well as in the creation of novel genetic variations through somaclonal variation.
• Genetic engineering techniques are utilized to produce transgenic plants with desirable genes like disease resistance, herbicide resistance, an increased shelf life of fruits etc.
• Molecular breeding to hasten the process of crop improvement.

3. Biotechnology in Industry:
Biotechnology is helpful in industries as:

• Industrial biotechnology is an area with which biotechnology is initiated for large scale production of alcohol and of antibiotics by microorganisms.
• A variety of pharmaceutical drugs and chemicals like lactic acid, glycerine etc. are being produced by genetic engineering for better quality and quantity.
• Fermented foods like pickles and yogurt are produced
• Malted foods like powdered milk are being produced
• Dairy products and vitamins are produced.

4. Biotechnology in the environment:
Environmental problems like pollution control, depletion of natural resources for nonrenewable energy, conservation of biodiversity etc. are being dealt with using biotechnology. For example:

• Bacteria are being utilized:
  * for detoxification of industrial effluents.
  * in combats oil spills for treatment of sewage.
  * for biogas production.
• Bio-pesticides give an environmentally safer alternative to chemical pesticides for control of insects, pest and diseases.

Q.5: What is fermentation? Describe the types of fermentation?
Ans: FERMENTATION:
The classical biotechnology that emerged during the early twentieth century was basically a microbial-based fermentation process in which the principles of biochemical engineering have been applied to change it into an industrial process.
Definition: Fermentation is an alternative term for Anaerobic respiration. It can be defined as:

"Fermentation is the process by which living organism such as yeast or bacteria are employed to produce useful compounds or products."
Or
"An important way of making ATP without oxygen is called fermentation."

TYPES OF FERMENTATION:
There are two major types:

1. Lactic acid fermentation
2. Alcoholic fermentation

1. LACTIC ACID FERMENTATION:
In lactic acid fermentation,  pyruvic acid from glycolysis changes to lactic acid. In this process, NAD⁺ forms NADH. The NAD⁺ cycles back to allow glycolysis to continue so more ATP is made. Each cycle represents as carbon atom.
Cause:
This type of fermentation is carried out by the bacteria Streptococcus and Lactobacillus species.
Uses:

• With the help of bacteria, this fermentation is used for souring milk into yogurt and production of various types of cheese.
• It is also used by our own muscle cells when we work them hard and fast.

2. ALCOHOL FERMENTATION:
In alcoholic fermentation, pyruvic acid is converted to alcohol and carbon dioxide. It produces ethanol and NAD⁺ from NADH. The NAD⁺ allows glycolysis to continue making ATP.
Ethanol fermentation converts two pyruvate molecules, the products of glycolysis into two molecules of ethanol and two molecules of carbon dioxide.
Cause:
This type of fermentation is carried out by yeast Saccharomyces cerevisiae and some bacteria.
Uses:

• It is used to make bread, wine, and biofuels.
• It also causes the rising of dough in breads. The yeast produces carbon dioxide gas in the dough using alcoholic fermentation. The gas forms bubbles which makes the dough rise and expand. The bubbles leave small holes in the bread after baking which makes the bread light and fluffy.

Q.6: Why fermentation can be referred to as industrial biotechnology?
Ans: Fermentation or Industrial Biotechnology:
Fermentation can be referred to as industrial biotechnology because it refers to the growth of microorganisms forming on food under either aerobic or anaerobic conditions. The industrial microorganisms are grown under controlled conditions with the aim of optimizing the growth of organism for the production of targeted microbial products such as food (cheese, yogurt, fermented pickles and sausages, soy sauce), beverages (beers, wines) and spirit.

Q.7: Write down the applications of fermentation?
Ans: APPLICATIONS OF FERMENTATION:

• Fermentation changes the chemical environment of a food.
• Fermentation is an important process in the preparation of food for human consumption. 
• Many plants undergo a fermentation process in order to produce the final products.
• Pre-sterilized (pasteurized) materials assembled into packages and aseptically filled (Aseptic packaging) for grocery shelf.
• Fermentation helps preserve the food and lower the need of refrigerator.

APPLICATION IN THE FOOD INDUSTRY
Fermentation as a food preservative technique:
Fermented foods are foods that have been prepared in a way so that the bacteria naturally found within them starts to ferment.
Lacto-fermentation, is a chemical process in which bacteria and other microorganisms break down starch and sugars within the foods, possibly making them easier to digest, and resulting in a product that is filled with helpful organisms and enzymes. This process of fermentation is a natural preservative, which means that fermented foods can last a long time.

Q.8: Write down products of fermentation?
Ans: PRODUCTS OF FERMENTATION:
Food products:
Foods that undergo fermentation are:

• Dairy products: Yogurt, cheese
• Cereal products: bread ,cakes
• Fruit and vegetable products: flavorings , candy, fruit juice, silage
• Beverages: beer, wine, cider
• Pickling:involves fermentation that are frequently pickled include beans, onions, cauliflower, cucumber, tomatoes cabbage.
• Microbial cells:
  * Yeast cells used in the baking industry.
  * Single-cell protein used as food material.

Non Food Products:
Non-food items that undergo fermentation include: 

• Laundry detergents
• Cellulose:
  * It is also used to produce bio-surfactant, polymers production such as bacterial cellulose production.
• Compost
• Chemicals
• Transformation products
  * Biofuels production (biodiesels, bioethanol, butanol, biohydrogen, bioplastic etc).
  * Bioremediation products involving microbes or their isolated enzymes for soils and waste water treatments (Wastewater, aromatics, toxic dyes etc.)

Medicine Products:

• Antibiotics
• Insulin
• Monoclonal antibodies
• Vaccines
• Medicines to dissolve tumors and to clot blood
• r DNA products:
  * Growth hormones
  * Interferon
• Enzymes:
  * Bacterial: amylase, protease, lipase.
  * Fungal: amylase, protease, pectinase.
• Metabolites:
  * Primary metabolites are proteins, vitamins, lipids, carbohydrates.
  * Secondary metabolites are enzymes, antimicrobial compounds, growth promoters.

Q.8: What is fermentor and its advantages?
Ans: FERMENTOR:
Definition:
In general term, as its name suggests:

"Fermentors are containers used to grow bacteria and fungi on large scale."

The general idea behind:

"The fermentor is to provide a stable and optimal environment for microorganisms to reproduce and interact with substrate for required product."

Advantages Of Fermentor:

1. Controlled Environment: For each biotechnological process, the environment provide to the organisms must be monitored and controlled. Such controlled environment is provided by fermentors.
2. Optimize Growth Of Organisms: A fermentor optimizes growth of organisms by controlling many factors like nutrients, oxygen, growth inhibitors pH and temperature.
3. Production in Bulk: A fermentor may hold several thousand liters of growth medium. So, fermentors allow the production of material in bulk quantities.
4. Production of Medicines: Massive amounts of medicines, insulin, human growth hormone and others protein are being produced in fermentors and thus production proves much inexpensive.
5. Minimized Wastage Of Materials: Wastage of materials in handling is minimized by fermentors. They can be installed with ease and take up very little space.

Q.9: What is genetic engineering? Write down its uses?
Ans: GENETIC ENGINEERING:
Genetic engineering is the cornerstone of modern biotechnology. It is based on scientific tools, developed in recent decades.
Uses:
It enable the researchers to:

• Identify the gene that produces the protein of interest.
• Cut the DNA sequence that contains the gene from a sample of DNA.
• Place the gene into a vector, such as a plasmid or a bacteriophage.
• Use the vector to carry the gene into the DNA of the host cells, such as escherichia coli (E coli) or mammalian cells grown in culture.
• Induce the cells to activate the gene and produce the desired protein.
• Extract and purify the protein for therapeutic use.

Q.10: Describe genetic engineering tools?
Ans: GENETIC ENGINEERING TOOLS
To manipulate cells and DNA, scientists use tools that are borrowed from nature. These include:

• Restriction enzymes:
  These naturally occurring enzymes are used as a defense by bacteria to cut up DNA from viruses. There are hundreds of specific restriction enzymes that researchers use like scissors to snip specific genes from DNA.
  
  
• DNA Ligase:
  This enzyme is used in nature to repair broken DNA. It can also be used to paste new genes into DNA.
  
  
• DNA vector:
  In molecular cloning, a vector is a DNA molecule used as a vehicle to artificially carry foreign genetic material into another cell, where it can be replicated. They include:
  a) Plasmids:
  They are mostly circular units of DNA. They can be engineered to carry genes of interest.
  b) Bacteriophages (also known as phages):
  These are viruses that can enter or infect bacteria. Bacteriophage can be engineered to carry recombinant DNA.
  
  
• Recombinant DNA technology:
  When segments of DNA are cut and pasted together to form new sequences, the result is known as recombinant DNA. When recombinant DNA is inserted into cells, the cells use this modified blueprint and their own cellular machinery to make the protein encoded by a recombinant DNA.
  
  
• Transgenic Cells:
  Cells that have recombinant DNA are known as Genetically Modified Organism (GMO) or transgenic cells. The GMO contains genes of interest and manufactures the desired products.

Q.11: Describe the major achievements of genetic engineering?
Ans: MAJOR ACHIEVEMENTS OF GENETIC ENGINEERING:
Genetic engineering means making changes to DNA in order to change the way living things work. So many things have been made through genetic engineering such as; Vaccines, Monoclonal antibodies, Gene therapy, Interferons, Interleukins, Recombinant human proteins, Human growth hormones, Clotting factors and Erythropoietins.

1. Vaccine against foot and mouth disease:
   The creation of new synthetic vaccine for foot and mouth diseases (a highly contagious viral disease that infects cattle, sheep, and other animals.) is strange and impressive achievement. The trick was to carve up the virus genome to make a DNA copy that codes only for the three capsid proteins.
   
   
2. Vaccine against coccidiosis:
   Coccidiosis is a disease of both invertebrates and vertebrates caused by parasitic protozoa which invade the epithelial cells lining the alimentary tract and the cells of associated glands. A vaccine made against coccidiosis by using avian protein to immunize chicken against avian coccidia.
   
   
3. Treatment of Trypanosomiasis:
   Sleeping sickness (trypanosomiasis) is caused by a parasite called Trypanosoma brucei. The availability of a genetic transformation made possible the treatment of this disease.
   
   
4. Genetic therapy:
   Molecular biology has introduced in modern medicine a new way to cure diseases, namely genetic therapy, direct intervention in the genetic makeup of an individual. Gene therapy can be somatic or germ line. It is being used to treat genetic disorders of the blood (e.g. thalassaemia).
   
   
5. Cloning Humans:
   In the second half of the 20th century, as dramatic advances were taking place in genetic knowledge, as well as in the genetic technology. Some proposals suggested that persons of great intellectual or artistic achievement or of great virtue be cloned.
   
   
6. Herbicides: Genetically modified (GM) foods possess specific traits such as tolerance to herbicides or resistance to insects or viruses.
   
   
7. Insect Killing Bacteria: Adding a gene from insect-killing bacteria to cotton so that insects, eat cotton will be poisoned!
   
   
8. Treatment Of Lung disease: Genetic engineering also includes insertion of human genes into sheep so that they secrete alpha-1 antitrypsin in their milk - a useful substance in treating some cases of lung disease.
   
   
9. Human insulin:
   By inserting a gene for human insulin into an E. coli bacterium, the E. coli will make a lots of insulin, which scientists and doctors can collect and use.
   
   
10. Cancer treatment: Scientists have found a gene called p-53 which normally keeps cells under control and works best to suppress cancer cells.
    

Q.12:What is single cell protein? Write down its uses?
Ans: Introduction:
When there were shortage in proteins and vitamins in the diet, the Germans produced yeast and a moulds (Geotrichum candidum) in some quantity for food, this led to the idea to produce edible proteins on a large scale by means of microorganisms.

Single-cell protein:
Single-Cell Protein (SCP) is a term coined at Massachusetts Institute of Technology by Prof. C. L. Wilson (1966) and represents microbial cells (primary) grown in mass culture harvested for use as protein sources in food or animal feeds.
Definition:

“The isolated protein or the total cell material from microorganisms like bacteria, yeast, filamentous fungi and algae contains carbohydrates, lipids, nucleic acid, mineral salts and vitamins, used as food or feed is called single-cell protein (SCP).”

Production OF SCP:

• Carbon substrates: Major substrates used in commercial SCP production are alcohol, n-alkanes, molasses, sulphite, liquor and whey.
• Substitute for protein-rich food: SCP is a protein is a protein extracted from cultured algae, yeasts, or bacteria and used as a substitute for protein rich food, especially in animal feeds or as dietary supplement.
• 60-80% dry cell weight: Many types of animal feeds contain single cell protein. 60-80% dry cell weight; contains nucleic acid, fats, CHO, vitamins, and minerals rich in essential amino acids (Lys-Met).
• Microbes: can be used to ferment some of the vast amount of waste materials, such as:
  * Straws
  * Wood and wood processing wastes
  * Food cannery and food processing wastes
  * Residues from alcohol production
  * From human and animal excreta

Q.13: Give reason?
(i) Did you ever run a race and notice that your muscles feel tired and sore afterwards. why?
Ans: This is because our muscle cells used lactic acid fermentation for energy. This causes lactic acid to build up in the muscles. It is the buildup of lactic acid that makes the muscles feel tired and sore.

(ii) Why small holes are formed in the sliced of bread?
Ans: The small holes are formed in the sliced of bread by bubbles of carbon dioxide gas. The gas was produced by alcoholic fermentation carried out by yeast.


Source: Special Thanks To Sir Syed Arif Ali