ISC Class 12 Specimen Paper 2020 for Biotechnology Paper 1

BIOTECHNOLOGY
PAPER 1
(THEORY)
(Maximum Marks: 70)
(Time allowed: Three hours)
(Candidates are allowed additional 15 minutes for only reading the paper.
They must NOT start writing during this time.)
Answer Question 1 (compulsory) from Part I and five questions from Part II.
The intended marks for questions or parts of questions are given in brackets [ ].
PART I (20 Marks)
Answer all questions.
Question 1
(a) Mention any one significant difference between each of the following: [5]
(i) Purines and pyrimidines.
(ii) Triploids and haploids.
(iii) Lac operon and Trp operon
(iv) Blunt end and sticky end.
(v) Genomics and proteomics.
(b) Answer the following questions: [5]
(i) Name the scientists who discovered the genetic code.
(ii) Name any two growth regulators used in a culture medium.
(iii) What are cell lines?
(iv) Name the vitamin present in golden rice.
(v) What is gynogenesis?
(c) Write the full form of each of the following: [5]
(i) ICMR
(ii) FBS
(iii) BAC
(iv) IEF
(v) PAGE

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(d) Explain briefly the following: [5]
(i) Polyadenylation
(ii) Reverse transcription
(iii) Edible vaccine
(iv) De differentiation
(v) Seedless crops

PART II (50 Marks)
Answer any five questions.

Question 2

(a) Briefly explain the structure of tRNA. Write its function in protein synthesis. [4]
(b) Write the use of the following instruments: [4]
(i) Centrifuge
(ii) LAF
(iii) T flask
(iv) Co2 incubator
(c) What is a DNA probe? [2]

Question 3

(a) Explain the process involved in the transcription of DNA to mRNA. [4]
(b) What are stem cells? Explain the various types of stem cells. [4]
(c) State the significance of Evan’s blue test. [2]

Question 4
(a) Explain the following methods of selection of recombinant cells: [4]
(i) Insertional inactivation.
(ii) Blue white colony
(b) Enumerate the steps involved in regenerating a plant from a single cell. [4]
(c) What is wobble effect? [2]
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Question 5
(a) Discuss the working of PCR technique in detail. [4]
(b) Explain the principle working and application of FACS. [4]
(c) Write two differences between Southern and Northern blotting techniques. [2]

Question 6
(a) Describe the procedure of sequencing of DNA by Sanger’s method. [4]
(b) Name and explain any two chemical methods used to synchronize suspension [4]
cultures.
(c) Name any two industrial enzymes and give their uses. [2]

Question 7
(a) Briefly explain the essential features of a vector. [4]
(b) What is the principle of cryopreservation? Mention the steps of cryopreservation. [4]
(c) What is the importance of pH and solidifying agents in cell cultures? [2]

Question 8

(a) Explain how rDNA technology has been used to create the following: [4]
(i) Tomatoes with delayed ripening.
(ii) Bt crops
(iii) Dolly sheep
(iv) Oil eating bacteria
(b) List the functions of the following bioinformatics tools: [4]
(i) GENSCAN
(ii) ENTREZ
(iii) FASTA
(iv) PIR
(c) Name any two media used in plant tissue culture. [2]
Question 9

(a) What are restriction enzymes? How do they work? What are the different types of [4]
restriction enzymes?

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(b) Draw a well labelled diagram of a bioreactor. [4]
(c) Differentiate between the following: [2]
(i) Local alignment and Global alignment.
(ii) EST and STS.

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