1. health and fitness
2. disease

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.
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?
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?
4
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.
1
15
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
16
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
2
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?
20
21
22
23
24
25
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
-----------
3
VI.
--Nucleotide sequences with single base differences
26
27
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
29
30
(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.
4
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
5
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
6
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
7
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
*****
8
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.
9
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)
10