It is possible to produce algae based biofuels, but what is/are the likely limitation(s) of developing countries in promoting this industry? 1. Production of algae based biofuels is possible in seas only and not on continents. 2. Setting up and engineering the algae based biofuel production requires high level of expertise/technology until the construction is completed. 3. Economically viable production necessitates the setting up of large scale facilities which may raise ecological and social concerns. Select the correct answer using the code given below.
- A.1 and 2 only
- B.2 and 3 only
- C.3 only
- D.1, 2 and 3
Correct answer
Explanation
The correct answer is B, 2 and 3 only. The real hurdles are the high technology needed to build algae plants and the very large scale they need to pay off; algae can be grown on land.
Algal biofuel, a third-generation biofuel, comes from microalgae rich in oils that can be turned into biodiesel or jet fuel. Algae grow fast and do not need farmland, but cultivating them in open raceway ponds or closed photobioreactors, harvesting them and extracting oil require advanced engineering and costly skills. To be cheap, plants must cover large areas and use much water, carbon dioxide and nutrients, which can raise land, water and local livelihood concerns.
A is wrong because statement 1 is false: algae are commonly grown on land in ponds, tanks, photobioreactors and even wastewater.
C is wrong because it leaves out the true statement 2.
D is wrong because it includes the false statement 1.
Exam tip: first generation = food crops, second = crop waste, third = algae.
Practice Questions
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- A.fertilization of egg in vitro by the donor sperm
- B.genetic modification of sperm producing cells
- C.development of stem cells into functional embryos
- D.prevention of mitochondrial diseases in offspring
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1. It can be integrated into any electronic device.
2. Online authentication using iris is possible.
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- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
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Read the full explanation →The main detector planned for the India-based Neutrino Observatory in Theni district is
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- B.a 50,000-tonne magnetised Iron CALorimeter
- C.a liquid argon time projection chamber
- D.a superconducting tokamak
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Read the full explanation →LIGO-India, the third detector of the LIGO network, is being set up at which place?
- A.Aundha, Hingoli district, Maharashtra
- B.Hanle, Ladakh
- C.Pottipuram, Theni district, Tamil Nadu
- D.Khodad, Pune district, Maharashtra
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Read the full explanation →Gravitational waves, first detected by LIGO in September 2015, had been predicted a century earlier by whom?
- A.Isaac Newton
- B.Albert Einstein
- C.Niels Bohr
- D.Stephen Hawking
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