Biology Sample Question Paper : www.nvsrochd.gov.in Navodaya Vidyalaya Samiti

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SAMPLE QUESTION PAPER XII- BIOLOGY
FROM JNV HAAMIRPUR [H.P.]

General Instructions:
(i) All questions are compulsory.
(ii) This question paper consists of four Sections A, B, C and D. Section A contains 8 questions of one mark each, Section B is of 10 questions of two marks each, Section C is of 9 questions of three marks each and
Section D is of 3 questions of five marks each.
(iii) There is no overall choice. However, an internal choice has been provided in one question of 2 marks, one question of 3 marks and all the three questions of 5 marks weightage. A student has to attempt only one of the alternatives in such questions.
(iv) Wherever necessary, the diagrams drawn should be neat and properly labelled.

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Section – A :
1 The turkey usually produces females for several generations. How is this possible?
3 After successful in-vitro fertilization, the fertilized egg begins to divide. Where is this egg transferred before it reaches the 8-cell stage and what is this technique named?
4 The gene I that controls the ABO blood grouping in human beings has three alleles IA, IB and i.
(a) How many different genotypes are likely to be present in the human population?
(b) Also, how many phenotypes are possibly present?
5 Expand the following (i) PCR (ii) Bt
6 State the use of:
(i) Trichoderma with respect to organ transplant, and
(ii) Nucleopolyhedrovirus with respect to pest management
7 In plants, how is alien DNA introduced into the host cell?
8 Cite an example of an inverted ecological pyramid. What kind of pyramid of energy would it have?

Section – B :
9 Among pea tendrils, Opuntia spines, lemon thorns and cucurbita tendrils, which ones are homologous structures and why?
10 i. In which disease is there an uncontrolled division of cells resulting in the formation of tumours? How this disease is detected?
ii. How do interferons help in controlling the disease?
11 What is allergy? Name the antibody responsible for it. Also mention two chemicals released from the mast cells during an allergic reaction.
12 Fed up of a large family, a couple wanted to adopt a terminal method of contraception. Describe the process conducted by the doctor in either of the cases (male / female partner)
OR
A mother of a one year old daughter wanted to space her second child. Her doctor suggested CuT. Explain its contraceptive actions.
13 You have developed a GM organism. Which government organisation will you approach to obtain clearance for its mass production? Why is such a body necessary? Give two reasons.
15 Fill in the blanks in the different columns of the table given below.
A Disease Causative agent
Medium of transfer Symptoms
Filariasis
Waucheria
B Lymphatic vessels of the lower limbs are affected
C Trichophyton
Using towels of infected person
Dry, scaly lesions on body Common cold
D Droplets from sneezing of infected persons
Affect nose and respiratory passage, sore throat Ascariasis Ascaris Through contaminated water, vegetables and fruits

16 Following are the steps in MOET programmme for herd improvement in which a cow has been administered hormones with FSH like activity. Arrange steps A to D in their correct sequence.
A - Transferred to a surrogate mother.
B - It is either mated with an elite bull or artificially inseminated.
C - Fertilized eggs at 32 cell stage are recovered non-surgically.
D - It produces 6-8 eggs instead of one egg which they normally yield per cycle.
17 Compare the grazing food chain and detritus food chain in the aspect of their
(a) origin and
(b) Energy status.
18 What is measured in BOD test? BOD level of three samples of water labelled as A, B and C are 30 mg /l, 10 mg /l
and 500 mg /l respectively. Which sample of water is most polluted?

Section – C :
20 A tRNA is charged with amino acid methionine
(i) Name the process involved in the attachment
(ii) Point out the mRNA codon and anticodon on tRNA for this amino acid.
(iii) What is heterochromatin?
21 A true breeding tall plant is crossed with a true breeding dwarf plant. F1 progeny is 100% tall and F2 has tall : dwarf in the ratio 3:1
(i) Explain why F1 shows only one type of parental phenotype;
(ii) Name the patterns of inheritance in which the ratio deviates from above.
(iii) Also mention the deviated phenotypic ratio.
22 (a) State Hardy Weinberg principle. Name any two factors which affect it.
(b) Draw a graph to show that natural selection leads to directional change.
OR
In the 1950s, there were hardly any mosquitoes in Delhi. The use of the pesticide DDT on standing water killed their larvae. It is believed that now there are mosquitoes because they evolved DDT resistance through the
interaction of mutation and Natural Selection. Point wise, state in a sequence how that could have happened.
23 Draw a labeled diagram of immunoglobulin.
24 With an example, explain how biotechnology has been applied in each of the following:
(i) In curing Diabetes mellitus
(ii) In curing SCID
(iii) In raising pest resistant plants
(iv) In producing more nutritionally balanced milk.
Do you think it is ethical to manipulate organisms for human benefits? Justify your answer. 25 Few gaps have been left in the following table showing certain terms and their meanings. Fill up the gaps.
TERMS
MEANINGS
I.
---
Non coding sequence in eukaryotic DNA
II.
---
Technique used in solving paternity disputes
III.
Restriction endonuclease
-----------
IV.
Plasmid
-----------
V.
Transgenesics
-----------
VI.
---
Nucleotide sequences with single base differences
26 Explain with reference to PCR
(a) A specific enzyme helps in amplification in PCR. Name the bacterium from which it is isolated and state how its thermo stable nature is helpful.
(b) Explain its use in molecular diagnosis.
27 What are “flocs”? State their role in effluent treatment and their ultimate fate in sewage treatment tank.

Section – D :
28 (a) Draw the embryo sac of a flowering plant and label
central cell
Chalazal end of the embryo sac
Synergids.
(b) Name the cell that develops into the embryo sac and explain how this cell leads to the formation of Embryo
sac. Also mention the role played by the various cells of the embryo sac.
OR
Show diagrammatically the stages of embryonic development from zygote up to implantation in humans. 29 Name the genes that constitute an operon. How does lac operon get switched on in the presence of lactose?
OR
With the advent of rDNA technology a powerful tool is available to identify a criminal or to the real parents. Name this technique. Write the missing steps in the procedure given below. There of three
steps are mentioned in the flow chart: Extraction of DNA from the cells - (ii)....................H(iii)
DNA is cut into fragments by restriction enzymes H (iv).................H (v)................H
(vi).................H (vii) Autoradiography. ................H (viii).................H
30 (a) On seeing the bad state of roads in your locality, as a student, you have recommended to the Municipal Corporation to use polyblend.
(i) What is polyblend? Point out its raw material?
(ii) How will it be advantageous?
(b) What are e-wastes? Explain the method of their disposal.
OR
(a) What is meant by ecological succession? How does it occur? Explain.
(b) Differentiate between Primary and Secondary succession.

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What are flocs and state their role in affluent treatment and their ultimate fate in sewage treatment tank?