Science and Technology (Part-II)

Total Questions: 50

1. The American multinational company, Monsanto, has produced an insect-resistant cotton variety that is undergoing field trials in India. A toxic gene from which one of the following bacteria has been transferred to this transgenic cotton? [2001]

Correct Answer: (b) Bacillus thuringiensis
Solution:Bacillus thuringiensis (Bt) is an insecticide with unusual properties that make it useful for pest control in certain situation. Br is a naturally occurring bacterium common in soils throughout the world. Several strains can infect and kill insects.
• Bacillus thuringiensis was discovered in 1901 by a Japanese biologist, Shigetane Ishiwatari.
• BT cotton has been genetically modified (GM) by inserting one or more genes from Bacillus thuringiensis, (a common soil bacterium) making them transgenic plants.
• The insertion of Bt. thuringiensis genes causes cotton plant cells to produce crystal insecticidal proteins known as Cryproteins.
• These insecticidal proteins are effective in killing some of the most damaging cotton caterpillar pests, such as tobacco budworm and bollworm larvae.
• Bollgard I: In 1996, Bollgard cotton (a trademark of Monsanto) was the first Bt cotton to be marketed in the United States. The original Bollgard cotton produces a toxin called Cry 1Ac, which has excellent activity against tobacco budworms and pink bollworm.
• Bollgard II: It was introduced in 2003, representing the next generation of Bt cotton. It contains a second gene from the Bt bacteria which encodes the production of Cry 2Ab.

2. With reference to the latest developments in stem cell research, consider the following statements : [2002]

1. The only source of human stem cells are the embryos at blastocyst stage.

2. The stem cells can be derived without caisining destruction to blastocysts.

3. The stem cells can regenerate themselves in vitro virtually forever.

4. Indian research centres also created a few cell lines which can be developed into many types of tissues.

Which of these statements are correct?

Correct Answer: (d) 3 and 4
Solution:Stem cells are a class of undifferentiated cells, that are able to differentiate into specialized cell types.

Sources are:

(i) Embryo formed during the blastocyst phase of embryological development.

(ii) Adult tissue (adulstem cells).

3. Which one of the following is the landmark performance of Dr. V. Mohan Reddy, an Indian, born doctor working in U.S.A. during February, 2005? [2005]

Correct Answer: (b) Successful open heart procedure called arterial switch performed on an infant.
Solution:

Dr. V. Mohan Reddy in February 2005 performed successful open heart surgery of premature baby of 700 gms.
• CABG is one of the most common Trusted Source types of open heart surgery. The coronary arteries supply the heart with blood. If the arteries become blocked or narrowed due to heart disease, a person may be at risk of a heart attack. The operation involves taking a healthy blood vessel from another part of the body and using it to bypass the blocked arteries.
• Another open heart procedure involves repairing or replacing a malfunctioning heart valve. Heart valves control the flow of blood in and out of the heart. When valves do not open and close as they should, it can put extra strainTrusted Source on the heart to pump more blood, which can result in heart failure. Valve repair involves strengthening the existing valves. Replacement involves removing them and implanting a mechanical valve, or one that comes from another human or animal.

4. Which one of the following Union Ministries is implementing the Biodiesel Mission (as Nodal Ministry)? [2008]

Correct Answer: (d) Ministry of Rural Development
Solution:

The Committee on Development of Bio-fuels set-up by the Planning Commission in July, 2002, in its report of April, 2003, recommended launching of the National Commission on Bio-diesel. Ministry of Rural development was designated as the Nodal Ministry for this Mission.
• Biofuels are renewable energy sources made from organic materials such as plants, algae, and animal waste.
• They can be converted into liquid fuels like ethanol, biodiesel, and biogas for use in transportation, heating, and electricity generation.
• Biofuels are considered eco-friendly alternatives to fossil fuels, reducing greenhouse gas emissions.
Types of Biofuels
• Ethanol: A type of alcohol made from fermented plant sugars, commonly used as a gasoline substitute or additive.
• Biodiesel: Derived from vegetable oils, animal fats, or algae, biodiesel can replace or blend with conventional diesel fuel.
• Biogas: Produced from the anaerobic digestion of organic materials, such as agricultural waste and landfill trash, used for heating or electricity generation.
• Bioethanol: Similar to ethanol, made from crops like corn or sugarcane, often used as a renewable fuel for vehicles.
• Algal Biofuels: Derived from algae, they have high energy yields and are seen as a promising alternative for transportation fuels.
• Biobutanol: A high-energy biofuel produced from plant sugars and biomass, considered a potential substitute for gasoline.
• Wood and Pellet Fuels: Solid biofuels made from wood, agricultural residues, or compressed sawdust, commonly used for heating and cooking.

5. In the context of alternative sources of energy, ethanol as a viable bio-fuel can be obtained from : [2008]

Correct Answer: (c) Sugarcane
Solution:Sugarcane ethanol is an alcohol-based fuel produced by the fermentation of sugarcane juice and molasses. Because it is a clean, affordable and low-carbon biofuel, sugarcane ethanol has emerged as a leading renewable fuel for the transportation sector.
• Biofuels are renewable energy sources made from organic materials such as plants, algae, and animal waste.
• They can be converted into liquid fuels like ethanol, biodiesel, and biogas for use in transportation, heating, and electricity generation.
• Biofuels are considered eco-friendly alternatives to fossil fuels, reducing greenhouse gas emissions.
Types of Biofuels
• Ethanol: A type of alcohol made from fermented plant sugars, commonly used as a gasoline substitute or additive.
• Biodiesel: Derived from vegetable oils, animal fats, or algae, biodiesel can replace or blend with conventional diesel fuel.
• Biogas: Produced from the anaerobic digestion of organic materials, such as agricultural waste and landfill trash, used for heating or electricity generation.
• Bioethanol: Similar to ethanol, made from crops like corn or sugarcane, often used as a renewable fuel for vehicles.
• Algal Biofuels: Derived from algae, they have high energy yields and are seen as a promising alternative for transportation fuels.
• Biobutanol: A high-energy biofuel produced from plant sugars and biomass, considered a potential substitute for gasoline.
• Wood and Pellet Fuels: Solid biofuels made from wood, agricultural residues, or compressed sawdust, commonly used for heating and cooking.

6. In the context of CO₂ emission and Global Warming, what is the name of a market driven device under the UNFCC that allows developing countries to get funds/ incentives from the developed countries to adopt better technologies that reduce greenhouse gas emissions? [2009]

Correct Answer: (c) Clean Development Mechanism
Solution:

• Article 12 of the Kyoto Protocol essentially defines the Clean Development Mechanism (CDM).
• The CDM permits the public and private sectors in high-income countries the chance to buy carbon credits from offset projects in low- or middle-income countries because it is the largest regulatory project-based mechanism.
• Such initiatives can generate saleable certified emission reduction (CER) credits, which are used to count toward achieving Kyoto commitments and are each equal to one tonne of CO2.
• It is the first worldwide environmental investment and credit program of its kind, offering CERs, a standardized mechanism for offsetting emissions.
• Many regard the mechanism as a trailblazer. It is the first global environmental investment and credit scheme of its kind, offering CERs as a standardised emissions offset instrument.
• For example, a CDM project activity could include rural electrification using solar panels or the installation of more energy-efficient boilers.

7. With reference to the treatment of cancerous tumours, a tool called cyberknife has been making the news. In this context, which one of the following statements is not correct? [2010]

Correct Answer: (d) It can map the spread of tumour in the body.
Solution:The statement "It can map the spread of the tumour in the body" is not correct. Cyber Knife is a robotic image-guided system that delivers an extremely precise dose of radiation with the capability of achieving sub-millimetre accuracy. However, it is not used to map the spread of the tumour in the body. Instead, other imaging techniques such as MRI, CT scan, or PET scan are used for the same.

8. Genetically modified "golden rice" has been engineered to meet human nutritional requirements. Which one of the following statements best qualifies golden rice? [2010]

Correct Answer: (b) Its grains contain pro-vitamin A which upon ingestion is converted to vitamin A in the human body.
Solution:

About Golden Rice:

  • It is a new type of rice that contains beta carotene (provitamin A, a plant pigment that the body converts into vitamin A as needed). This compound is what gives this grain its yellow-orange or golden color.
  • It is developed through genetic engineering.
  • While ordinary rice does produce beta carotene, it is not found in the grain. Thus, scientists used genetic engineering to add the compound to the grain – a minor tweak that improved the grain’s nutritive value.
  • The beta carotene in Golden Rice, which was made possible by the addition of two new enzymes, is identical to the beta-carotene found in green leafy and yellow-colored vegetables, orange-colored fruit, and even in many vitamin supplements and food ingredients.
  • Like ordinary rice, Golden Rice does not require any special cultivation practices, and generally has the same yield and agronomic performance.
  • This rice is expected to cost and taste the same as regular rice, its beta carotene content makes it a valuable asset in the battle against Vitamin A deficiency (VAD).
  • Vitamin A is an essential micronutrient for growth, development, and keeping the body’s visual and immune systems healthy.
  • VAD weakens the body’s resistance to diseases and infections, causes blindness, and may even result in death if left untreated.

9. Recently, "oil zapper" was in the news. What is it ? [2011-1]

Correct Answer: (a) It is an eco-friendly technology for the remediation of oily sludge and oil spills
Solution:
  • Oil Zapper is an innovative bioremediation technology aimed at alleviating the environmental threat of oil spills in aquatic and terrestrial ecosystems.
  • Against the backdrop of growing urgency for cleanup, Oil Zapper utilizes a consortium of so-called Application-Selected bacterial strains that are capable of degradation of different fractions of crude oil and oily sludge.
  • The technology is targeted at providing a sustainable and efficient manner for site restoration that is minimising ecological damage and fostering environmental recovery.
    Effectiveness of Oil Zapper

The Oil Zapper works by a unique mixture of four bacterial strains. These bacterial strains get chosen due to their ability to degrade different fractions of crude oil, including.

  • Aliphatic Hydrocarbons: Straight or branched-chain hydrocarbons are abundant in crude oil. These bacteria degrade these compounds into less harmful ones.
  • Aromatic Hydrocarbons: These compounds with complex ring structures are often more difficult to degrade. The bacterial strains used in Oil Zapper have enzymes that break down these compounds.
  • Asphaltenes: These heavy fractions of crude oil are rather stable and resistant to degradation. The bacterial consortium includes strains which can modify and degrade asphaltenes into less polymerized intermediates towards biodegradation.
  • NSO Compounds: Compounds with nitrogen, sulfur, and oxygen are also found in crude oil and oily sludge. The bacterial strains degrade these compounds causing accumulation of toxic substances in the environment.

10. A genetically engineered form of brinjal, known as the Bt-brinjal, has been developed. The objective of this is : [2011 -1]

Correct Answer: (a) to make it pest-resistant.
Solution:

The brinjal is highly susceptible to pest attacks, of which the fruit and shoot borers cause the most damage in terms of yield. Primarily, it is to address this pest that the genetically modified (GM)Bt brinjal has been developed by Mahyco Monsanto Biotech. It is a joint venture between Maharashtra Hybrid Seed Company and the US seed giant Monsanto.
This brinjal contains the Bacillus thuringiensis (Bt) gene, which is said to provide resistance to lepidopteran insects such as the brinjal fruit and shoot borer (FSB) Leucinodes orbonalis and the fruit borer Helicoverpa armigera. Bt Brinjal has not been approved for commercial cultivation in India