Science & Technology GK Questions with Answers – Page 6

The Centre for DNA Fingerprinting and Diagnostics was established in 1995 as an autonomous institution of the Department of Biotechnology and works at Hyderabad on DNA fingerprinting services, diagnostics of genetic disorders and research in genomics.

In the Watson and Crick model the two strands are held together by hydrogen bonds between complementary bases: adenine pairs with thymine through two hydrogen bonds and guanine pairs with cytosine through three.

The polymerase chain reaction, invented by Kary Mullis in 1983, repeats three steps: the DNA is denatured near ninety-five degrees Celsius, short primers anneal at a lower temperature, and the strand is extended at about seventy-two degrees.

The Human Genome Project was launched in 1990 as an international public effort coordinated in the United States by the National Institutes of Health and the Department of Energy, with laboratories in several countries taking part.

Each nucleotide of DNA carries a phosphate group, and the phosphate backbone gives the whole molecule a net negative charge at the pH used in the laboratory.

Cas9 is an enzyme that breaks the sugar-phosphate backbone of both DNA strands at the point where its guide RNA has bound, provided a short adjacent signal called the PAM is present.

The two scientists showed that the bacterial CRISPR-Cas9 system could be directed by a designed guide RNA to cut any chosen sequence of DNA, which turned a microbial defence mechanism into a general tool for editing genomes, and they shared the Nobel Prize in Chemistry in 2020.

Working at the University of Leicester in 1984, Alec Jeffreys found that certain short sequences, the minisatellites or variable number tandem repeats, repeat a different number of times in different people, and that a pattern made from them identifies an individual.

The telescope sits near the second Lagrange point (L2), about 1.5 million km from Earth, and goes round the Sun along with the Earth.

Because the rotor carries permanent magnets instead of windings that must be energised, the motor is compact, light and highly efficient over a wide range of speeds, and it gives the strong torque from rest that makes electric cars quick off the mark.

A fuel cell is an electrochemical device, not an engine: hydrogen fed to the anode is split into protons and electrons, the protons cross a membrane, the electrons travel through the external circuit and do work, and at the cathode they recombine with oxygen from the air to form water.

The Battery Waste Management Rules, 2022 were notified under the Environment (Protection) Act and replaced the Batteries (Management and Handling) Rules of 2001.

The BMS is the electronic brain of the pack. It measures the voltage, current and temperature of individual cells or groups of cells, balances their charge so that no cell is overworked, estimates the state of charge and state of health that the dashboard displays, and disconnects the pack when…

The Geological Survey of India reported an inferred lithium resource in the Salal and Haimana area of that district, the first lithium find of real consequence in the country and a significant one because India had been importing virtually all its lithium and its cells.

The second phase shifted the emphasis from private cars to public and shared transport, concentrating its incentives on electric buses, two wheelers, three wheelers and commercial four wheelers, and tying them to conditions on battery type and on the share of parts made in India, while also funding charging stations.

The scheme for Faster Adoption and Manufacturing of Hybrid and Electric Vehicles is a demand and manufacturing support scheme, offering incentives that reduce the purchase price of eligible vehicles and funding charging infrastructure, and it sits with the ministry responsible for the automobile and capital goods industries.

When the driver lifts off or brakes, the electric motor is made to work backwards: the turning wheels drive it, it generates electricity, and that current is fed back into the pack.

LFP cells are prized for safety, long cycle life and the absence of cobalt, which makes them cheaper and less exposed to supply disruption; their weakness is a lower energy density, so a pack of the same range weighs more.

The layered structure of graphite can accept lithium ions between its sheets, a process called intercalation, and release them again without breaking down, which is what makes the cell rechargeable over hundreds of cycles.

Whittingham built the first working lithium cell in the 1970s, Goodenough found that a lithium cobalt oxide cathode could give a far higher voltage, and Yoshino replaced the dangerous metallic lithium anode with a carbon material, producing the safe, rechargeable cell that was commercialised in 1991.