SAMPLE QUESTION PAPER XII- BIOLOGY FROM JNV ...

SAMPLE QUESTION PAPER XII- BIOLOGY FROM JNV HAAMIRPUR [H.P.] Time: 3 Hrs

MM: 70

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. Section – A 1 2

The turkey usually produces females for several generations. How is this possible? In the following pedigree chart, find out the trait is autosomal dominant, autosomal recessive or sex linked. Give a reason for your answer.

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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? 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? Expand the following (i) PCR (ii) Bt State the use of: (i) Trichoderma with respect to organ transplant, and (ii) Nucleopolyhedrovirus with respect to pest management In plants, how is alien DNA introduced into the host cell? Cite an example of an inverted ecological pyramid. What kind of pyramid of energy would it have?

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5 6

7 8

Section – B 9 10

11 12

13 14

Among pea tendrils, Opuntia spines, lemon thorns and cucurbita tendrils, which ones are homologous structures and why? 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? What is allergy? Name the antibody responsible for it. Also mention two chemicals released from the mast cells during an allergic reaction. 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. 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. In the T.S. of a mature anther given below identify “A” and “B” and mention their function.

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Fill in the blanks in the different columns of the table given below. Disease Causative agent Medium of transfer Symptoms

Filariasis Waucheria A Lymphatic vessels of the lower limbs are affected

B Trichophyton Using towels of infected person Dry, scaly lesions on body

Common cold C Droplets from sneezing of infected persons Affect nose and respiratory passage, sore throat

Ascariasis Ascaris Through contaminated water, vegetables and fruits D

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17

18

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. Compare the grazing food chain and detritus food chain in the aspect of their (a) origin and (b) Energy status. 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 19

The events of the menstrual cycle are represented below. Answer the questions following the diagram. (i) State the levels of FSH, LH and Progesterone simply

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by mentioning high or low, around 13th and 14th day and 21st to 23 rd day (ii) In which of the above mentioned phases does the egg travel to the fallopian tube? (iii) Why is there no menstruation upon fertilization?

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23 24

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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? 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. (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. Draw a labeled diagram of immunoglobulin. 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. 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 -----------

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VI. --Nucleotide sequences with single base differences

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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. What are “flocs”? State their role in effluent treatment and their ultimate fate in sewage treatment tank.

Section – D 28

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(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. 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)....................→(iii) DNA is cut into fragments by restriction enzymes → (iv).................→ (v)................→ (vi).................→ (vii) Autoradiography. ................→ (viii).................→ (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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MARKING SCHEME SAMPLE QUESTION PAPER XII – BIOLOGY Section – A A1 A2 A3 A4 A5 A6

A7 A8

In a turkey, female gametes undergo development without fertilization. This phenomenon is called parthenogenesis. Autosomal dominant; defective trait in both male and female progeny /unaffected child did not pass down trait. Fallopian tube/oviduct; ZIFT/zygote intra fallopian transfer (a) 6, (b) 4 Polymerase chain reaction; Bacillus thuringiensis (No mark if specific name written with capital T) a: Trichoderma - Biocontrol agent of several plant pathogens/ produces Cyclosporin A which is used as an immunosuppressive agent in organ transplant patients b. Nucleopolyhedrovirus - Narrow spectrum insecticide The plant cells are bombarded with high velocity micro - particles of gold or tungsten coated with DNA in a method known as biolistics or gene gun. Sea/Forest/Large tree Upright

[1 Mark] [1/2+1/2] [1/2+1/2] [1/2+1/2] [1/2+1/2] [1/2+1/2]

[1 Mark] [1/2+1/2]

Section – B B9 B10

B11

B12

B13

B14 B15

B16

B17

B18

Pea tendrils and Opuntia spines are homologous as both are modified leaves, While lemon thorns and cucurbita tendrils are homologous as both are stem modifications. i. Disease characterized by uncontrolled division of cells is called cancer. It can be detected by- Biopsy (e.g. Pap smear test), DNA probes, Tumor markers, endoscopy, radiological techniques ii. Interferons are anti-viral proteins which are produced by virus infected cells and prepare the non-infected cells to resist the viral attack. The exaggerated response of the immune system to certain antigens present in the environment IgE Histamine and serotonin Male Partner: Vasectomy - a small part of the vas deferens is removed or tied up through a small incision in the scrotum. Female Partner: Tubectomy - a small part of the fallopian tube is removed or tied up through a small incision in the abdomen or through vagina. OR CuT release Cu ions, increases phagocytosis of sperms, suppresses sperm motility, and reduces fertilizing capacity. I. GEAC - Genetic Engineering Approval Committee II. Makes decisions regarding validity of GM research; Checks safety of introducing GM-organisms for public services. A - Sporogenous tissue; form microspores or pollen grains. B - Tapetum; nourishes the developing pollen grains. A. Injected into the blood of human with the saliva of culex and ades mosquitoes B. Ringworms C. Rhinovirus D. Abdominal pain, indigestion, anemia, weakness, vomiting, diarrhoea, enteritis, appendicitis, nervous disorders A. It produces 6-8 eggs instead of one egg which they normally yield per cycle B. It is either mated with an elite bull or artificially inseminated C. Fertilized eggs at 32 cell stage are recovered non - surgically D. Transferred to surrogate mothers A. Grazing food chain starts from producers while detritus food chain starts from organic matter B. Grazing food chain is the major media of energy flow in an ecosystem BOD test measures rate of uptake of O2 by microorganisms in a sample of water. Greater the BOD of water, more is pollution Sample ‘C’ is most polluted because it has highest BOD level among the three samples of water = 1

1+1 1/2 X2 +1

1/2 1/2 1/2 X 2 1+1

1/2 X 4 1 1/2 X 2 1/2 X 4 1/2 X 4

1/2 X 4

1+1

1+1

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Section – C C19

C20

C21

C22

i) FSH and LH : high and progesterone low; FSH and LH : Low and Progesterone high; (ii) Luteal phase (iii) uterine wall and blood vessels help maintain implanted embryo; i) Initiation (ii) mRNA codon = AUG (iii) The densely packed and dark stained / transcripitionally inactive chromatin is called as heterochromatin (a) Case of dominance where allele T is dominant over allele t that is both heterozygous and homozygous dominant expresses the dominant trait. (b) Case of incomplete dominance/ Co-dominance (c)1 : 2 : 1 (a) Allelic frequencies in a population are stable and constant from generation to generation. (b) Gene flow, genetic drift, mutation, genetic recombination, natural selection

1/2 +1/2 1 1 1+1+1

1+1+1

1+1+1

(c) a) b) c) C23

C24

C25

C26

C27

OR Certain larvae born with mutation; which conferred resistance to DDT; DDT sensitive larvae died; DDT resistant larvae completed life history and became adult mosquitoes; Natural selection caused greater reproduction of DDT resistant mosquitoes; which soon replaced DDT sensitive mosquitoes. Diagram Labeling

(i) production of insulin to cure Diabetes mellitus (ii) gene therapy for cure of ADA (iii) using Agrobacterium vectors to introduce nematode specific genes or RNAi (iv) Generating transgenic cow such as Rosie. Ethical standards required as genetically manipulated organisms may harm other organisms/results unpredictable. i. Intron ii. DNA finger printing iii. cuts specific nucleotide sequence iv. extrachromosomal DNA in bacteria/vector v. modified organisms/ organisms with foreign gene vi. SNP (a) Thermus aquaticus (b) It remains active during the high temperature induced denaturation (c) Very low concentration of a bacteria or virus can be detected by amplification of their nucleic acid by PCR (a) Masses of aerobic bacteria associated with fungal filaments (b) While growing they consume large amount of organic matter of the effluents reducing BOD (c) When effluent goes to settling tank and flocs are allowed to sediment for activated sludge, they get digested by anaerobic bacteria

1 1/2 X 4

1/2 X 4

1 1/2 x 6

1+1+1

1+1+1

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Section – D D 28

i. The functional megaspore develops into embryo sac ii. Nucleus undergoes mitotic division and the two cells move to the opposite poles iii. Two successive mitotic division - an eight nucleate embryo sac iv. Cell wall formation takes place after nuclear divisins v. Three cells group together at the micropylar end - egg apparatus with an egg cell and two synergids vi. Three cells group together at the Chalazal end - antipodal cells vii. The remaining two nuclei move to the centre - fuse to form secondary nucleus.

OR A Zygote B 2 celled stage Cleavage C 4 celled stage D Morula with vitelline membrane E Blastocyst with trophoblast and inner cell mass F Implantation f blastocys G In the endometrium within wall

D 29

D 30

i. Regulator gene, Promoter gene. Operator gene and structural gene 1. An inducible operon where Lactose is the inducer and it is the substrate for the enzyme B-galactosidase 2. Three structural genes (z, y, a) which transcribe the polycistronic mRNA 3. z codes for - galactosidase, y for permease and a for transacetylase 4. Near the structural genes is the promoter gene where RNA polymerase binds for transcription 5. An operator gene as a switch near the promoter where a repressor always binds. 6. Repressor protein coded by the i gene prevents the RNA polymerase from transcribing by binding to the operator 7. Lactose, an inducer inactivates the repressor and prevents it from binding to the operator. 8. Allows an access for the RNA polymerase to the promoter 9. Transcription takes place 10. The substrate lactose regulates the lac-operon. OR DNA finger printing ; (i)Extraction of DNA from the cells (ii) Amplification by polymerase chain reaction (iii) DNA is cut into fragments by restriction enzymes (iv) Separation of DNA fragments by gel electrophoresis (v) Southern blotting (vi) Hybridization using probe fragment (vii) Autoradiography (viii) Matching of DNA fragment photographs and interpretation. (a) It is a fine powder of recycled modified plastic. This mixture is mixed with bitumen used to lay roads Raw material - Plastic film waste (ii) Blends of polyblend & bitumen, when used to lay roads, enhance the bitumen’s water repellant properties and helps to increase road life. (b) Irreparable computers and other electronic goods are known as e-wastes Burried in landfills or incinerated = 1

2+ 1/2 X 6

2 +1/2 X 6

1/2 X 10

1 x5

1 1 1 1 1

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OR (a) The gradual and fairly predictable change in the species composition of a given area (b) During succession some species colonise an area & their populations become more numerous, whereas populations of other species decline and even disappear Primary Succession Secondary Succession

1 1 1 2

It occurs in an area which has been bare from the beginning. It occurs in an area which has been denuded recently.

Soil is absent at the time of beginning of primary succession. Soil is present in the area where secondary succession begins.

Takes a long time for completion. Takes less time for completion

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DESIGN OF THE QUESTION PAPER BIOLOGY-CLASS XII Hrs: 3 Hrs.

Max. Marks: 70

The weightage of the distribution of marks over different dimensions of the question paper shall be as follows: Weightage to content/subject units Units Content Marks 1 2 3 4 5

Reproduction Genetics and evolution Biology and Human Welfare Biotechnology and its applications Ecology and environment Total

14 18 14 10 14 70

Weightage to different form of questions S. No. Form of Questions Marks for each

No. of Questions

Total Marks

1 2 3 4 5

08 10 09 03 30

08 20 27 15 70

Very Short Answer (VSA) Short Answer (SA I) Short Answer (SA II) Long Answer (LA)

1 2 3 5 TOTAL

Scheme of Options 1. There will be no overall option. 2. Internal choices (either/or type) on a very selective basis has been provided. This choice has been given in one question of 2 marks, one question of 3 marks and all the three questions of 5 marks weightage. Weightage to difficulty level of questions. S.No. Estimated difficulty level

Percentage

1 2 3

15 70 15

Easy Average Difficult

About 20% weightage has been assigned to questions testing higher order thinking skills of learners.

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BLUE PRINT BIOLOGY CLASS XII S.No.

TYPES OF QUESTIONS→

VSA

SA I

SA II

LA

TOTAL

UNITS↓

1

Reproduction

2 (2)

4 (2)

3 (1)

5 (1)

14 (6)

2

Genetics and evolution

2 (2)

2 (1)

9 (3)

5 (1)

18 (7)

3

Biology and Human Welfare

1 (1)

10 (5)

3 (1)

----

14 (7)

4

Biotechnology and its applications

1 (1)

---

9 (3)

----

10 (4)

5

Ecology and environment

2 (2)

4 (2)

3 (1)

5 (1)

14 (6)

TOTAL

8 (8)

20 (10)

27 (9)

15 (3) 70 (30)

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