GK Questions with related facts|Kerala PSC GK question sand answers

 GK Questions with related facts|Kerala PSC GK question sand answers

1. The first genetically modified crop (GM crop) introduced in

India is

a) Antibiotic resistant tobacco b) Flavr savr tomato

c) Bt cotton d) Bt Brinjal

The correct answer is 'c'

In India, the first GM crop "Bt cotton'' was introduced in

2002 against the cotton bollworm which was major pest of

the crop. Till then the farmers have been using multiple

sprayings of chemical pesticide against this pest. Bt cotton

contains the 'cry' gene obtained from Bacillus thuringiensis

bacteria which can produce the insecticidal 'cry protein'. When

the bollworm feeds on Bt cotton plant, the cry protein enters

into the midgut and becomes endotoxin which binds to midgut epithelial cells and forms pores or holes in the cell membrane and ultimately kills the insect. Antibiotic resistant tobacco was the first GM crop plant in the world developed in

ANALYSE YOUR SCIENCE GK

1983. In 1992, China was the first country to approve commercialization of GM tobacco resistant to cucumber mosaic

virus. In 1994, the US also approved the first GM tomato,

''Flavr Savr'' for commercialization. There are certain questions about the biosafety of Bt Brinjal that delays the commercialization of that GM crop in India.

2. Most jewellery is made of 22 carat gold. What is the percentage of gold in it?

a) 90 % b) 92 %

c) 24% d) 22%

The Correct answer is 'b'

The purity of gold in alloy is measured in 'carats'. Pure

gold is 24 carat with no other metals. Therefore 22 carat

gold means that it contains 22 parts of gold and remaining

any other metals. Thus percentage of gold in 22 carat gold

alloy is 100 91 .7 %

24

22 × =

3. Name the nitrogen base that is not seen in DNA, the genetic

material of organisms

a) Adenine b) Thymine

c) Cytosine d) Uracil

The correct answer is 'd'

The Two nucleic acids seen in organisms are DNA (Deoxy

ribo nucleic acid) and RNA (Ribonucleic acid). The nucleic

acids are polymers of nucleotides. Each nucleotide consists of a phosphate group, a pentose sugar and one

nitrogen base. The nitrogen bases are of two types- Purines and Pyrimidines. Adenine (A) and Guanine (G) are

purines and where as Cytosine (C), Thymine (T) and Uracil

(U) are Pyrimidine bases. DNA is composed of several

nucleotides having phosphate group, deoxy ribose sugar

and the bases A, T, G and C. RNA, which is single stranded,

is a polymer of ribo nucleotides with phosphate group. ribose sugar and the bases A, G, C and U. Therefore

Thymine (T) is absent in RNA.

4. Which one of the following is a scalar quantity?

a) Displacement b) Density

c) Velocity d) Acceleration

The Correct answer is 'b'

Physical quantities can be divided into vector quantities

and scalar quantities. A physical quantity which has magnitude

and direction is called vector quantity. eg: Displacement, Velocity, Acceleration etc. The Physical quantity that can be described completely by its magnitude only is referred as scalar

quantity. eg: Mass, Volume, Density, Power etc.

5. Which of the antibiotics is a narrow spectrum one?

a) Penicillin G b) Ampicillin

c) Chloramphenicol d) Vancomycin

The Correct answer is 'a'

Antibiotics are chemical substances produced by microbes

for their safety, used for killing other attacking microbes.

Antibiotics are produced synthetically by man and used

against the disease causing microbes. Broad spectrum antibiotics will kill or inhibit a wide range of both gram positive

and gram negative bacteria. eg: Ampicillin, Chloramphenicol, Vancomycin etc. Narrow spectrum antibiotics are specific against a limited number of pathogens. Penicillin G is an

example which is used to test the patient's sensitivity of Penicillin, before its administration.