Matric Notes Biology Class 10th Ch 17 Bio-Technology Extra Short and Long Questions

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Q1: What is biotechnology?

Ans: Biotechnology: The using of living organisms and their product for the welfare of human beings, other animals and crops is known as biotechnology.

Explanation: Biotechnology is being used sine prehistoric times. When man started to plant their own crops and to breed their own animals, they usually started biotechnology. They discovered the conversion of fruit juices into alcohol by fermentation. They also discovered the conversion of milk into cheese and yogurt. When the soft and spongy bread was made by the first maker then they were acting as biotechnologist.

Q2: What do you know about fermentation and its types?

Ans: Fermentation: Fermentation is the chemical conversion of sugar solutions into ethanol and lactic acid in the absence of oxygen.

Bacteria and yeast: Fermentation is done with the help of microscope such as bacteria and yeast. These microorganisms obtained energy during fermentation.

Zymology: The science of fermentation is known as zymology.

Fermentation products: Various fermentation products are: Yogurt, pickle, etc.

Types of fermentation: Fermentation as a type of cellular respiration:

a. Alcoholic fermentation by yeast cells: Alcoholic fermentation is two-step process.

Process:

1st step: In this fermentation, the glucose molecule is first broken down into two molecules of pyruvic acid. This step is called glycolysis.

2nd step: In the next step, pyruvic acid is further broken down into carbon dioxide and ethanol.

Example: This fermentation occurs in yeast (Saccharomyces cerevisiae). Scientist use this process to produce alcohol during the making of alcoholic products, ethanol fuel and bread.

b. Lactic acid fermentation by bacteria: Lactic acid is also takes place in two steps:

Process:

1st step: The first step is similar to alcoholic fermentation. The glucose molecule is broken down into two molecule of pyruvic acid.

2nd step: In the second step, hydrogen is added to pyruvic acid (reduction), which changes it to lactic acid.

Example: This fermentation occurs in bacteria e.g.:

✓ Lactobacillus
✓ Streptococcus

Lactic acid fermentation done by bacteria is used to turn milk into yogurt.

Q3:What do you know about some fermentation products.

Ans: There are the following fermentation product:

Alcohol: Alcohol is made as a result of fermentation of a natural source of sugar with a catalyst, which is usually yeast. During fermentation, the carbohydrates(starch and sugar) are the main source which are converted into CO2 and ethyl alcohol. Alcohol is widely used in medicines.

Soy sauce: It is made by fermentation of soyabean by fungi.

Chocolate: When cacao beans undergoes the process of fermentation then chocolate is produced.

Many chemical products: Many chemical products are produced through the fermentation process e.g formic acid , glycerol and acrylic acid etc.

Q4: What are the types of fermentation?

Ans: Fermentation: Fermentation is the chemical conversion of sugar solutions into ethanol and lactic acid in the absence of oxygen. It is an anaerobic process in which energy can be released from glucose.

Types of fermentation: There are two types of fermentation.

➢ Batch fermentation
➢ Continues fermentation

➢ Batch fermentation: In this process, the tank of fermenter is filled with the raw material to be fermented. The temperature and pH for the microbial fermentation is properly adjusted, and nutritive supplements are added. All the material are stem sterilized, the pure culture of microorganism is added to fermenter from a separate vessel. Fermentation proceeds and after the proper time contents of fermenter are taken out. Fermenter is cleaned and the process is repeated. Thus, fermentation is a discontinues process divided into batches.

➢ Continues fermentation: In this process, the substrate is added to fermenter continuously at a fixed rate. This maintain the microorganisms in growth phase. Fermentation products are taken out continuously.

The design and arrangement for the continues fermentation are more complex.

Q5: What are the advantages of the fermenter?

Ans: Advantages of the fermenter: There are the following advantages of the fermenter:

• Fermenter have an auto control system so environmental changes cannot harm microbial growth.
• Separation of product is easy and safe.
• Inoculation of microbes is easy.
• Wastage of material in handling is minimized by fermenter.
• They can be installed with ease and take up very little space.
• Single fermenter can be used for production of a wide range of products.
• Fermenter enable the production of medical product, such as penicillin, insulin, erythromycin, streptomycin, griseofulvin (Antifungal antibiotic) and hundreds of others product from microbes.

Q6: What is genetic engineering? Write its advantages and disadvantages.

Ans: Genetic engineering: Genetic engineering is that are of biotechnology which includes DNA alteration, artificial manipulation and transfer of genetic material from one organisms into another organisms.

Recombinant DNA technology: In genetic engineering the genes of different organisms are combined together which is known as recombinant DNA technology. The recombinant DNA technology is a technology where the selected DNA of an organisms is introduced with the DNA of another organisms.

Advantages:

✓ Several important species such as carrot, cabbage, citrus and potatoes can be grown from single cell.
✓ When a gene is introduced into a cell a clone of that cell can produce countless altered progeny.
✓ Genes can be duplicated countless times to produce large quantities.

Disadvantages: Most plant characteristic are polygenic and controlled by many genes such as growth rate, size of edible parts etc. So, it is very difficult to clone five or more genes which control a characters.

Q7: What are various objectives or goals of genetic engineering?

Ans: Main objective of genetic engineering:

The main objective of genetic engineering are:

• Identify and isolate genes that cause disease, with a view to repair or eradicate them so that their harmful effects are negated.
• Find remedies and therapies to treat non-genetic diseases.
• Develop more sophisticated and effective medicines through genetic engineering for example bio-engineered insulin and human growth hormones (somatotropin).
• Genetically modified organisms (GMOs) are produced to enhance the food production. Genetically modified crops and cattle produce more food in lesser time. They are made disease resistant so that loses due to pathogens can be reduced.
• Plants are genetically modified to get substances which they do not produce naturally such as antibiotic, certain protein, hormones, etc.

Q8: What are the basic tools required for genetic engineering?

Ans: Basic tools of genetic engineering: The following two enzymes which are used in genetic engineering are known as basic tools required for genetic engineering.

➢ Restriction endonuclease
➢ DNA ligase

➢ Restriction endonuclease: Restriction endonuclease was discovered in 1970. They are used in cutting DNA at a specific site, so they are called molecular scissors.

➢ DNA ligase: DNA ligase was discovered in 1966. It is used to join DNA fragments and are called a paste molecule.

Q9: What are the basic techniques of genetic engineering?

Ans: Basic techniques of genetic engineering: Basic techniques of genetic engineering are as follows:

➢ Isolation of gene of interest: The gene (DNA) of donor organisms or gene of interest is identified. It is then isolated from the chromosomes of the donor by using restriction endonucleases.

➢ Making recombinant DNA: The gene of interest is attached to a suitable vector (cloning vector), to carry the gene to the host organism.

Vector: The most common vector used in the genetic engineering is plasmids. It is extra chromosomal circular DNA of Escherichia coli. Bacteriophage (viruses that can enters bacteria) are also used as vector.

Process: The DNA of the vector is cut into fragments by the restriction endonuclease. Using the enzyme DNA ligase, the DNA fragments of the donor and vector are joined together. As a result recombinant DNA is obtained.

➢ Gene cloning: The recombinant DNA is introduced into the host bacterial cells. The host cell is treated with the enzyme so that their cell wall becomes permeable for the recombinant DNA. Each colony is grown separately to get a number of colonies having identical copies of recombinant DNA. This is called DNA cloning.

As a result of the transfer of the donor’s genes into the bacteria, the bacteria are genetically modified. The start preparing the product by using the donor’s gene.

Q10: What are the achievements of genetic engineering in curing animal disease?

Ans: Achievements in curing animal disease:

Human insulin: Human insulin was the first genetic engineering product. In 1982, the human gene for insulin was inserted into bacterium. Since then, the modified bacteria are providing large amounts of human insulin.

Vaccine against hepatitis B: Vaccine against hepatitis B virus has been produced from yeast through genetic modification.

Interferon (anti-virus protein): Interferon (anti-virus protein) is made in genetically modified bacteria.

Vaccine against Foot and mouth diseases: Vaccine against Foot and mouth diseases are being developed for foot and mouth disease, a highly contagious viral diseases that infects cattle, sheep, and other animals.

Vaccine against Coccidiosis: Vaccine against Coccidiosis ( a parasitic disease of the intestinal tract of animals). This vaccines kills protozoan that causes caccidiosis.

Treatment of Trypanosomiasis: Treatment of Trypanosomiasis ( sleeping sickness) may be possible through use of biotechnological techniques. Trypanosomiasis is a parasitic infection transmitted by a fly in humans and other animals. Genetic engineers are doing research to develop such proteins which can kill the parasites of these disease.

Gene therapy: Gene therapy enables the treatment of genetic disorders. Through this technique genetic engineers treat genetic disorders by introducing a gene into the patient cell. It is being used to treat genetic disorders of the blood (e.g. thalassaemia).

Animal cloning: Animal cloning has become possible due to biotechnology. Genetic engineers have successively cloned mice, sheep , cows and others mammals. The basic idea behind cloning of animals is to transfer the readymade DNA into the egg and create identical organism. In this method, the genetic information from a cell of the animals to be cloned is transfer to an egg whose nucleus has been removed. Then the egg with the new genetic material is stimulated to divide and make a multicellular embryo. When this embryo is sufficiently developed , it is implanted into the uterus of a female host, who acts as its surrogate mothers. The rest of the developing of the embryo happens just like a normal organisms. When the development is complete the new animals is the exact cloned of the parent whose nucleus was used.

Example: Dolly the sheep was cloned using this process by the Roslin Institute in Scotland in 1977.

Q11: What are the drawbacks of using single cell protein?

Ans: Drawbacks of using single cell protein: There are the following drawbacks of using single cell protein:

✓ The high nucleic acid content ( 4 to 6% in algae and 6 to 10% in yeast of SCP) can cause health problem like uric acid formation, kidney stones and rheumatism in human beings.
✓ Toxic or carcinogens (cancer causing) substances absorbed from microbial growth substrate may be present.
✓ The slow digestion of microbial cell in the digestive tract may cause vomiting, indigestion and allergic reaction.
✓ High cost of production will also be a deciding factor in determining the ultimate place SCP in the human or animal diet.