UPSC Prelims 2014 · GS Paper I
Question 72: Science and Technology
Consider the following techniques/phenomena :
- 1.Budding and grafting in fruit plants
- 2.Cytoplasmic male sterility
- 3.Gene silencing
Which of the above is/are used to create transgenic crops?
AnswerUPSC’s answer is (b).
Transgenic crops carry a gene put in from another organism. Cytoplasmic male sterility is used with genetic engineering (for example the barnase system) to produce male-sterile lines for hybrid seed, and gene silencing (RNA interference) is used to switch off an unwanted gene in a transgenic plant. Budding and grafting are only methods of vegetative propagation by joining plant parts, and they do not transfer genes.
- 1. Budding and grafting join plant parts and do not transfer genes.
- 2. Male sterility is engineered into plants for hybrid seed production.
- 3. Gene silencing switches off a gene in transgenic plants.
Why each option is right or wrong
- (a) Wrong. Budding and grafting are vegetative propagation and do not create transgenics.
- (b) Right. Male sterility and gene silencing are used in transgenic crops.
- (c) Wrong. Budding and grafting do not transfer genes.
- (d) Wrong. Statements 2 and 3 are used in making transgenic crops.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2014, General Studies Paper I, Series A. The paper on upsc.gov.in.