ANALYSIS OF ‘RDT & TECHNIQUES’ FOR CSIR-NET EXAM (UNIT-13)

ANALYSIS OF   ‘RDT & TECHNIQUES’   FOR CSIR-NET EXAM

(CSIR-NET - UNIT 13) 

Dr. VINEET SHARMA

(For Grassroots Academy, Delhi)

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Dear students,

Table 1: Year wise Analyses
Year	Section B	Section C
June 2011	3	8
Dec 2011	4	9
June 2012	5	6
Dec 2012	3	6
June 2013	3	3
Dec 2013	3	9
June 2014	6	8
Dec 2014	6	4
June 2015	4	9
Dec 2015	7	7
June 2016	6	8
Dec 2016	4	5
June 2017	7	9
Dec 2017	6	14

As promised, please find this blog in continuation of our previous analyses about recent trends followed in CSIR-NET Exam. We understand the dilemma of the students at this crucial juncture, when the exam is at your doorstep and still much is left for revision. We at Grassroots Academy care about you and take responsibility to analyze trends in some of the key sections over the past couple of years.

One of the important portions in CSIR NET exam is UNIT 13. This domain constitutes RDT, Biophysical Methods, Microscopy, Biostatistics and other key techniques. At first glance, it seems to be a bulky and boring unit. To your surprise, this unit infact is the most rewarding unit in the entire syllabus. Every year an average 10-15 questions / year are asked, which is a significant portion (see Table 1). If you design your preparation systematically, then these questions can enrich you by atleast 35 - 50 marks.  

Furthermore, we performed topic wise analysis of questions. We found that based on one’s time invested and reward obtained, Unit 13 can be roughly divided into three major categories i.e.

a.       Recombinant DNA Technology.

b.      Principles and Techniques; Spectroscopy, Immuno-techniques and Microscopic Methods;

c.       Rest of the Unit 13.

1.   Recombinant DNA Technology: Principles and Techniques

In RDT section, conceptual questions are generally asked from vectors used in bacterial, plants and animal systems. In past, lot of questions have been asked from Plasmids, YACs and plant based vectors especially Agrobacterium tumefaciens (Ti Plasmid). Another important area is Restriction Enzymes and their use in restriction mapping. Basic knowledge of restriction sites and cleavage pattern is essentially required to attempt such questions. For this you may brush up your lecture notes. Some of the representative questions are

Q Which of the following statements about YACs is FALSE?

a)   YACs can carry DNA fragments of 1Mb                                  

b)   A single yeast may contain more than one YAC

c)   Rearrangements in YACs are rare because recombination is poor in yeast   

d)  YACs have to be transferred to bacteria for subsequent DNA manipulations

RDT techniques is another area, from which regularly questions have been asked. You may need not to cover entire techniques, rather focus on PCR, Sequencing methods and tools of polymorphism analysis (RAPD, RFLP, AFLP and SSR).  From 2011-2016, sum total of 18 questions were asked from these three methods. 

UNIT 13 Topics		Jun-11	Dec-11	Jun-12	Dec-12	Jun-13	Dec-13	Jun-14	Dec-14	Jun-15	Dec-15	Jun-16	Dec-16	Jun-17	Dec-17
Recombinant DNA Technology Principles & Methods	Plasmids, Viral Vectors, Cosmids, BAC, PAC, YAC	2	1	1	1	1		1		1	1				1
	Vectors of Plants and Animals	2	1					2		1			1	3	3
	Transformation & Expression Studies	1		1						1	1	2			1
	Restriction Enz& Mapping	1		2			1	2		1			1	1	1
Recombinant DNA Technology: Techniques	Polymerase Chain Reaction	1	1	1					1						1
	Sequencing Methods; Microarray &Bioinformatic Analysis	1	2	1		1	1	1			2	1
	Molecular Marker Analysis; RFLP, AFLP, RAPD, SSR		1					1				2
	Molecular Breeding & Transgenic& Gene Therapy	1									1			1
Histochemical &Immuno Techniques	ELISA, RIA, Western Blot, Chip, FISH & GISH		2	3	2		1		3	1	2	1	1	1	1
Spectroscopy	UV-Vis, NMR, CD, SPR	1		1	3	2	3	1	2	2	3	3	4	3	3
Microscopy	Light, TEM, SEM, FRAP, Cryo-methods	1	1		1		2	1		1	1	1	1		3
Chromatography	GPC, IEC, HIC, Affinity								1		1	1		2
Electrophoreis	SDS-PAGE, IEF, Hybridization		1		1		2	3		2			1	1
Statistics	Sampling Methods, Probability, Significance		1	1	1		1	2	1	2		2		2
Radiolabelling	Radioisotopes, Measurements, Imaging		1			1				1	1	1	1		1
Electrophysiolocial Methods	PET, MRI, CAT, EEG, ECG, Patch Clamp		1				1		2					1	4
Field Methods	Population estimation, patterns, remote sensing					1
Centrifugation	Rate zonal, Gradient, Ultra										1			1	1
Total Questions		11	13	11	9	6	12	14	10	13	14	14	10	16	20

2.   Immuno-techniques, Spectroscopy and Microscopic Methods

These three topics covered 38% of the total questions asked from UNIT 13 (2011-2017). At Grassroots, these topics were covered in detail supported by extensive illustrations and problem solving. As must be clear from above table, students must develop a good base in these topics. Some of the immunological methods like ELISA, RIA, Western Blot, FISH and GISH are very important from exam point of view.

Biophysical methods like UV-Vis, CD and NMR have been constantly trending in the recent exams. Many of these techniques are either covered along with the biomolecules or covered in classes pertaining to Techniques. Kindly revise the notes about the use of UV-spectroscopy in protein characterization and how CD spectroscopy can be used for the determination of helical conformation. Some of question asked in CSIR-NET exams are given below.

Q  Whichoneofthefollowingstatements regardingproteins is CORRECT?

a)      nàσ*transition requires less energy than nàπ*transition andcan be monitored by mass spectrometry.

b)      nàπ*transition requires more energy than π à  π*transition andcan be monitored by UV-Visspectroscopy.

c)      nàπ*transition requires less energythan n àσ*transition and can be monitored by CD spectroscopy.

d)      σà σ* transition requires less energy than nàπ*transition andcan be monitored by CD spectroscopy

Q   A polymer is synthesized from an achiral amino acid. Conformation of the polymer can be investigated by the following techniques.

A.  Fibre diffraction 

B.   Nuclear magnetic resonance spectroscopy

C.   Circular dichroism spectroscopy

D.  Differential scanning calorimetry

Choose the combination which would indicate that the polymer adopts a helical conformation

a)   A, C

b)   B, D

c)   A, B

d)   C, D

In microscopy, Fluorescent microscopic (FRAP) and Electron Microscopicmethods (TEM & SEM) are routinely asked. Please go through with basics of atleast these two topics.

3.   Rest of the contents of Unit 13.

Finally in rest of the Unit, you may pick up one or two sections, which are frequently covered. Atleast one question from statistical methods is commonly asked each year. This section demands more time for grasping the concepts. If Mathematics falls in your strong zone, then this section will be fruitful and may be given importance.

Student may revise their notes on electro-physiological methods. Important topics from this section are Patch clamp method, MRI, PET, EEG and ECG. Just brush up the concept and common applications of these methods.

In biochemical separation methods, Affinity chromatography is very important. In electrophoresis section, SDS-PAGE, Isoelectric focusing Hybridization methods should be covered. Representative question asked in past year is given below:

Q  Several fusion constructs were developed to purify heterologous protein in E. coli. The table below lists fusion partners and ligands.

	Partner		Ligand
i	Maltose binding protein	a	Specific monoclonal antibody
ii	Streptavidin	b	Nickel
iii	Glutathione-S-transferase	c	Glutathione
iv	Flag-tag	d	Amylose
v	6-Histidine tag	e	Biotin

Which one of the following is the correct match of the fusion partner with the ligand?

a)      i-b;   ii-d;   iii-c;   iv-a;   v-e

b)      i-d;   ii-b;   iii-e;    iv-c;   v-a

c)      i-d;   ii-e;   iii-c;    iv-a;  v-b

d)      i-c;   ii-d;   iii-a;    iv-b;   v-e

Final piece of advice at this moment is, do not rush for every topic given in CSIR-NET syllabus. Try to look for your strong areas and brush them up to the level of excellence, as this is high time to brush up the concepts rather than wiping out the syllabus.We hope this analyses will be helpful in designing your preparation. An investment of time on this area of the syllabus is well worth the effort.

All the very best for your Exams…. Keep visiting for more updates.....       

Regards

GRASSROOTS ACADEMY

www.grassrootsacademy.in