PSEB 12th Model Test Paper 2023 Biology

SampleQuestionPaper
10+2Biology
Note:

1. Question paper has four partsA,B,C, Dwith total17 questions.

2. Section-A has question number 1 having 28 parts of 1 mark each. 16 questions are MCQ
type,6 fillin theblanks and 6 are True/false.

3. Section-B has questions number 2 to 11-total 10 short answer type questions of 2 marks
each. Question4,6,9,10 haveinternalchoice.

4. Section-C has questions number 12 to 15 – total 4 questions of 3 marks each. Question 14
and 15 have internal choice.

5. Section-D has question 16 and question 17 -total 2 questions of 5 marks each. Both
questions have100% internal choice.

SectionA
Q1)
Eachquestioncarriesonemark

I. Asexual reproduction in Penicillium occurs through the formationof
A. Conidia
B. Gemmules
C. Rhizome
D. Offset
II. Thefemale gametophyte of a typical dicot atthetime of fertilisation is
A. 8 – celled
B. 7 – celled
C. 6 – celled
D. 5 – celled
III. Doublefertilization isfusion of
A. Twoeggs
B. Twoeggs and polar nuclei
C. One malegametewith egg and other with synergid
D. One malegametewith egg and other with secondary nucleus
IV. Oral contraceptives are used by females tocheck
A. Implantation
B. Fertilization

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C. Ovulation
D. Entryof sperm
V. SickleCell anaemia is caused due to
A. Protozoa
B. Virus
C. Bacteria
D. is agenetic disorder
VI. Which blood group is universal donor
A. A
B. AB
C. B
D. O
VII. In E. coli the Lac Operon getswitched on when
A. Lactoseis presentand it bindstorepressor
B. Repressorbinds to operator
C. RNApolymerasebindstooperator
D. Lactoseis absent
VIII. Thebonesof forelimbs of whale,bat,cheeah and man aresimilarin structure,because
A. One organismhas given risetoanother
B. they sharea common ancestor
C. they performthesamefunction.
D. thehave biochemical similarities.
IX. Which of thefollowing is hallucinogen?
A. LSD
B. Heroin
C. Cocaine
D. Morphine
X. Thetechniqueof obtaining largenumberof plantletsby tissue culturemethod is
called :
A. Organ culture
B. Micro-propagation
C. Macro-propagation
D. Plantlet culture
XI. If BOD of samplewater isvery high,thesample is
A. highly polluted
B. less polluted
C. not polluted
D. Potable
XII. Which of the following drug was firstproduced by sacrificing animals but is now
produced by rDNA technology?
A. Pencillin
B. Insulin
C. Paracetamol
D. Bttoxin
XIII. Theprincipleof competitive exclusion wasstated by
A. G. F. Gause

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B. G.J. Mendel
C. Charles Darwin
D. Watson and Crick
XIV. Which of the following is ex-situ modeof conservation of biodiversity?
A. NationalPark
B. Sacred grooves
C. Cryopreservation
D. Biospherereserve
XV. Chlorofluorocarbon are responsiblefor:
A. Acid rain
B. Ozone layerdepletion
C. Global warming
D. Thermalinversion
XVI. Which oneof thefollowing isnota greenhousegas?
A. Methane
B. CO2
C. Chlorofluorocarbon
D. Hydrogen
WriteTrueorFalse
XVII. Androgensareproduced by Leydig cells.
XVIII. AIDS spread duetoinfected blood,needles and syringes.
XIX. Insulin consistsof 4 short polypeptidechains named aschainA,chain B,Chain Cand
chain D
XX. Rearing and breeding of fishes forfood is called pisciculture.
XXI. Thehistorical convention onbiological diversity (TheEarth Summit) was held in Rio de
Janerioin 1992.
XXII. Plants arecalled producers becausethey fixatmospheric carbon dioxide.
Fillintheblanks
XXIII. Haemophilia and Colour blindness are… … … … ..linked disorders.
XXIV. Asequenceof threenitrogen bases thatcodeforan amino acid is called… … … … ..
XXV. Whenhostis exposed to antigens,antibodies areproduced in the host body. This type
of immunity iscalled … … … ...Immunity
XXVI. TheResidue left afterMethaneproduction fromcattledung is used as … … … … … ..
XXVII. Largescaleproduction of biotechnologicalproducts involves useof… … … … … ..
XXVIII. Dead plant partsand animal remains arecalled … … … … … … … .
SectionB
Eachquestioncarries2marks.
Q2) Draw alabelled diagramforstructure of ovum.
Q3) Writea note on tubectomy.
OR
Expand
GIFT
IVF
Q4) Whatis codominance? Give anexample.
OR
Defineand design a test cross

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Q5) Enlisttwoessential roles of ribosomeduring translation
Q6) What are homologous organs? Givean example.
Q7) What measures would you taketopreventwater borne diseases.
Q8) What are methanogens? Giveoneexample.
Q9) What are ‘ molecular scissors’ ? Givean example.
OR
Discuss theethicalissues related to biodiversity.
Q10) What are cry proteins? Name the organism that produces it.
Q11) Defineparasitism. Givean example.
OR
Namethree important levels of biodiversity.

SectionC

Q12) Discussthenatureof genetic code.
Q13) “ Convergent evolution leads toanalogous organs” Explain with example.
Q14) Name the causing agent of pneumonia. Alsowritedown its symptoms and
modes of transmission.
OR
Expand MOET. How is it carried out?
Q15) In recombinantDNAtechnology,vectors areused to transfera geneof interest
in the host cells. Mention any threefeatures of vectors that aremost suitable for this
purpose.
OR
What is genetherapy? Illustrate using the exampleof adenosine deaminase
deficiency.
SectionD

Q16) Define pollination. Writeany threecharacteristics of wind pollinated flowers.
OR
Observe the given diagram and answer the following questions.

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A. What does this diagram depict? 1
B. Label theparts Aand B. 1X2=2
C. Which oneof thesperms would reach theovum earlier? 1
D. Name the specific region inthefemale reproductive systemwhere the event
represented in thediagramtakes place. 1
Q17) Observe the phosphorouscycle given belowand answerthefollowing
questions

Fill in the blanks
Thenatural reservoir of phosphorous is… … … … … .,which contain
phosphorous in theformof phosphates. 2

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Thephosphorous from rocks is dissolved fromrocks insoilsolution bythe
processof … … … ? 2
Whetherthefollowing statement os trueor false?
Thephosphorous is returned to atmosphereby the respiratoryactivitiesof
consumers. 1

OR
Why does ozoneholeformoverAntarctica? How will enhanced ultraviolet
radiation affectus?

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