WORKSHEET - Delhi Directorate of Education · Identify each part in a flowering plant and write whether it is haploid (n) or diploid (2n) (5) ... of cell division occurs during these

1 [XII – Biology]

Name ________________________ Roll No. _______

WORKSHEET

1. Potato tuber is considered as a stem. Give two reasons. (1)

2. Rearrange the following events of sexual reproduction in the sequencein which they occur in a flowering plant:embryogenesis, fertilisation, gametogenesis, pollination. (1)

3. Give the scientific name of a plant which came to India as a contaminantwith imported wheat and causes pollen allergy. (1)

4. What do the ovary and ovule of a flower develop into after fertilisation?(1)

5. Honey bees produce their young ones only by sexual reproduction. Despiteof this, in a colony of bees we find both haploid and diploid individuals.Name the haploid and diploid individuals in the colony. (1)

6. Study the relationship between first two words and suggest a suitableword for fourth place.(i) Birds : oviparous : Primates : .................................(ii) Chlamydomonas : Zoospores :: Penicillium : .................................(iii) Ginger : Rhizome : Agave : .................................(iv) Male lower : Stamens : Female flower : ................................. (2)

7. Fill the blank spaces a, b, c, and d given in the following table. (2)

Organism Organ Gamete

a Testes Spermatozoa

Human female b Ovum

Plant (Angiosperm) c Pollen grains

Plant (pteridophytes) Antheridium d

[XII – Biology] 2

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8. Distinguish between gametogenesis and embryogenesis. (3)

9. Define : (a) zoospore, (b) zygospore and (c) zygote (3)

10. (A) Explain why meiosis and gametogenesis are always interlinked?(2)

(B) Define external fertilization. Mention its disadvantages. (3)

3 [XII – Biology]

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WORKSHEET

1. Note the relationship between the first two words and suggest a suitableword. (5)

(a) Root system : Stock :: Shoot system : ......................

(b) Asexual reproduction :: Uniparental :: Bisexual reproduction :.......................

(c) Chlamydomonas : Zoospore :: Penicillin : ........................

(d) Eyes : Potato :: ......................... : Ginger

(e) Leaf bud of Bryophyllum :: Offset : ......................

2. If the chromosome numbers in the gametes of Apple and maize are 17and 10, respectively, what will be the numbers in meiocytes of theseorganism? (2)

3. Choose the correct answer : (3)

(a) Bulbils are employed for multiplication of :

(i) Bryophyllum (ii) Crocus

(iii) Agave (iv) Strawberry

(b) A plant flowered once in 12 years in the month of September –October 2006. Its mass flowering transformed large tracks of hillyareas in Kerala, Karnataka and Tamil Nadu into blue stretches. Thename of the plant is :

(i) Bamboo species (ii) Strobilanthus kurthiana

(iii) Aloevera (iv) Agave

(c) The cause of “Terror of Bengal” was due to enormous vegetativegrowth of :

[XII – Biology] 4

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(i) Bryophyllum (ii) Water hyacinth

(iii) Hydrilla (iv) Ceratophyllum

4. Identify each part in a flowering plant and write whether it is haploid (n)or diploid (2n) (5)

(a) Ovary (b) Pollen

(c) Zygote (d) Egg

(e) Anther

5 [XII – Biology]

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WORKSHEET

1. Offspring formed by asexual method of reproduction are referred to asclones, why? (1)

2. Both cotyledons and nucellus perform a common function, what is that? (1)

3. In case of polyembryony, if an embryo develops from the synergid andanother from the nucellus which is haploid and which diploid? (1)

4. What is the function of the two male gametes produced by each pollengrain in angiosperm? (1)

5. Outer envelop of pollen grain made of a highly resistant substance. Whatis that substance? At which particular point the substance is not present?

(1)

6. Why does the zygote begin to divide only after the division of Primaryedosperm cell (PEC)? (2)

7. Among the animal, insects particularly bees are the dominant pollinatingagents. List any four characteristic features of the insect pollinated flower.

(2)

8. Continued self pollination lead to inbreeding depression. List three devices,which flowering plant have developed to discourage self pollination? (3)

9. Differentiate between microsporogenesis and megasporogenesis. What typeof cell division occurs during these events. Name the structure formed atthe end of these two events. (3)

10. Draw the embryo sac of a flowering plants and label : (5)

(a) (i) Central Cell (ii) Chalazal end (iii) Synergids

(b) Name the cell that develops into embryo sac and explain how thiscell leads to formation of embryo sac.

(c) Mention the role played by various cells of embryo sac.

(d) Give the role of filiform apparatus.

[XII – Biology] 6

Name ________________________ Roll No. _______

WORKSHEET

1. Complete the following flow chart : (1)

Pollen mother cell Pollen tetrad Pollen grain

Vegetative cell

.........................

2. Indicate the stage where meiosis occurs is the given flow chart :– (1)

Megaspore mother cell (1) Megaspores (2) Embryo sac (3)Egg

3. In the T-S of a mature anther given below, identify ‘a’ and ‘b’ and mentiontheir function. (2)

ab

4. If the diploid number of chromosomes of an angiospermic plant is 20, whatwould be the number in embryo and endosperm? (2)

5. (i) Pollination by bat is called..............................

(ii) Pollination by birds is called.......................... (2)

7 [XII – Biology]

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6. Choose the correct option :

(a) Ubisch bodies are found in :

(i) Endothecium (ii) Middle layers

(iii) Tapetum (iv) Sporogenous tissue (1)

(b) Germ pore is the region where the exine is

(i) Thin (ii) Absent

(iii) Uniform (iv) Thick (1)

(c) The outermost layer of maize endosperm is called

(i) Perisperm (ii) Aleurone

(iii) Tapetum (iv) Endothecium (1)

7. In the given figure, label the part which is protective in function and thatwhich is responsible for producing new plant. (4)

[XII – Biology] 8

Name ________________________ Roll No. _______

WORKSHEET

1. Given below are the events in human reproduction, Write them in correctorder :

Insemination, gametogenesis, fertilisation, parturition, gestation, implantation(1)

2. Both vaccine and colostrum produce immunity. Name type of immunityproduced by these. (1)

3. What is the significance of ampullary–isthmic junction in the femalereproductive tract. (1)

4. Mention the importance of LH surge during menstrual cycle. (1)

5. In ovary which structure transforms as corpus luteum and name thehormone secreted by corpus luteum? (1)

6. Why doctors recommend breast feeding during initial period of infant growth?(2)

7. Give a schematic labelled diagram to represent oogenesis (withoutdescriptions) (2)

8. T.S. of mammalian testis revealing seminiferous tubules show differenttypes of cell.

(i) Name the two types of cells of germinal epithelium.

(ii) Name of cells scattered in connective tissue and lying betweenseminiferous.

Differentiate between them on the basis of their functions. (3)

9. What is foetal ejection reflex? Explain how it leads to parturition? (3)

10. Draw a neat diagram of the female reproductive system and label the partsassociated with the following (a) production of gamete, (b) site of fertilisation(c) site of implantation and, (d) birth canal.

9 [XII – Biology]

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WORKSHEET

1. Female reproductive organs and associated functions are given below inColumn A and Column B. Fill in the blank boxes. (2)

Column A Column B

Ovaries Ovulation

Oviduct A

B Pregnancy

Vagina Birth

2. Study the figure and answer the questions. (5)

Inner Cell Mass

a

(a) Name the stage of human embryo the figure represents

(b) Identify ‘a’ and give its function

(c) Mention the fate of the inner cell mass after implantation in theuterus

(d) Where are stem cells located in this embryo.

3. What is the number of chromosomes in the following cells of a humanmale?

(i) Spermatogonial cells (ii) Sertoli cells

(ii) Spermatids (iv) Primary spermatocyte

[XII – Biology] 10

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4. Complete :

(1) Estrogen : Graffian follicle :: Progesterone : ......................

(2) Sertoli cells : Testes :: Leydig cells : .......................

(3) Male : Vasectomy :: Female : .........................

(4) Fertilisation : Fallopian Tube :: Implantation : ........................

11 [XII – Biology]

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WORKSHEET

1. Name the oral contraceptive developed by CDRI, Lucknow. (1)

2. Give technical name of female used to bring up in vitro fertilized egg tomaturity. (1)

3. Males in whom testes fail to descend to the scrotum are generally infertile.Why? (1)

4. Mention two advantages of lactational amenorrhea as a contraceptivemethod. (1)

5. Give the term for rapid population growth. (1)

6. Copper ions-releasing IUDs are more efficient than non-medicated methods.Why? (2)

7. Comment on the essential features required for an ideal contraceptive.(2)

8. Brief explain IVF and ET. What are the conditions in which these methodsare advised? (3)

9. Differentiate between Vasectomy and Tubectomy. (3)

10. Briefly explain the various reproductive technologies to assist an infertilecouple to have children. (5)


Name ________________________ Roll No. _______

WORKSHEET

1. Give the full form of MTP (1)

2. Explain the term GIFT (1)

3. Differentiate between tubectomy and vasectomy (2)

4. Briefly outline the reasons for human population explosion (2)

5. Describe chemical methods of birth control. (2)

6. Explain the Zygote Intra Fallopian Transfer technique (ZIFT). How is IntraUterine Transfer technique (IUT) different from it? (2)

7. What are STDs? Name some STDs. How can they be prevented? (3)

8. How can zero population growth be achieved. (3)

9. Write a short note on test tube baby. (3)

10. Cu-T prevents pregnancy by preventing :–

(a) Fertilization (b) Ovulation

(c) Implantation of Fertilized egg (d) None of the above. (1)


Name ________________________ Roll No. _______

WORKSHEET

1. A haemophilic man marries a normal homozygous woman. What is theprobability that their daughter will be haemophilic? (1)

2. A test is performed to know whether the given plant is homozygous dominantor heterozygous. Name the test and phenotypic ratio of this test for amonohybrid cross. (1)

3. Name the disorder with the following chromosome complement. (1)

I. 22 pairs of autosomes + XXY

II. 22 pairs of autosomes + 21st chromosome + XY.

4. In our society a woman is often blamed for not bearing male child. Do youthink it is right? Justify. (1)

5. Discuss the genetic basis of wrinkled phenotype of pea seed. (1)

6. Can a child have blood group O if his parents have blood group ‘A’ and ‘B’.Explain (2)

7. What is Down’s syndrome? Give its symptoms and cause. (2)

8. With the help of an example differentiate between incomplete dominanceand codominance. (3)

9. In Mendel’s breeding experiment on garden pea, the offspring of F2generation are obtained in the ratio of 25% pure yellow pod, 50% hybridgreen pods and 25% green pods State (i) which pod colour is dominant(ii) The Phenotypes of the individuals of F1 generation, (iii) Workout thecross. (3)

10. (a) In humans, males are heterogametic and females are homogametic.Explain. Are there any examples where males are homogametic and femalesheterogametic?

(b) Also describes as to, who determines the sex of an unborn child?Mention whether temperature has a role in sex determination. (5)


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WORKSHEET

1. What do you understand by terms allele and genotype? (1)

2. Aa Bb was crossed with aa bb. What would be the phenotypic ratio ofProgeny? Mention the term to denote this kind of cross. (1)

3. How many genes are responsible for

(i) ABO system of blood group

(ii) Skin colour in human (2)

4. Name the type of inheritance in which genotypic ratio is the same as thephenotypic ratio. Also give the ratio. (2)

5. What is crossing over? In which stage of cell division it taken place?(2)

6. What are liked genes? How can a pair of liked genes be identified?(2)

7. Explain the sex determination mechanism in humans. How is it different inbirds? (3)

8. A woman with blood group O married a man with AB group show thepossible blood groups of progeny list the alleles involved in this inheritance.

(3)

9. State and explain Mandel’s Law of independent assortment. (4)


Name ________________________ Roll No. _______

WORKSHEET

1. Name the factors for RNA polymerase enzyme which recognises the startand termination signals on DNA for transcription process in Bacteria.

(1)

2. During translation what role is preformed by t RNA? (1)

3. RNA viruses mutate and evolve faster than other viruses. Why? (1)

4. Mention the dual functions of AUG. (1)

5. Write the segment of RNA transcribed from the given DNA. (1)

3’. A T G C A G T A C G T C G T A - 5’ - Template Strand

5’ . T A C G T C A T G C A G C A T - 3’ - Coding Strand

6. Complete the blanks a, b, c and d on the basis of Frederick GriffithExperiment. (2)

S Strain inject into mice (a)

R Strain inject into mice (b)

S Strain (heat killed) inject into mice (c)

S Strain (heat killed) + R strain (live) inject into mice (d)

7. State the 4 criteria which a molecule must fulfill to act as a genetic material.(2)

8. Explain the process of splicing, capping and tailing which occur duringtranscription in Eukaryotes. (3)

9. Give any six features of the human genome. (3)

10. ‘There is a paternity dispute for a child’. Which technique can solve theproblem. Discuss the principle involved. (5)


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WORKSHEET

(A) Give one word for the following :–

(i) Positively charged basic proteins found in Nucleosome....................

(ii) Enzyme used in DNA Replication............................

(iii) Size of haploid Human Genome............................

(iv) Proof of DNA to be the genetic material given by............................

(v) The strand in DNA which transcribes the RNA............................

(vi) Loosely packed chromatin in a Nucleus............................

(vii) Enzyme which join DNA fragments............................

(viii) Coding sequence present in a mature RNA............................

(ix) Process of making DNA from RNA............................

(x) Site where DNA Replication begins............................

(B) Fill in the crossword using the clues given below :

6

37

102

11

8

5

9

41


Name ________________________ Roll No. _______

Across Down

1. DNA double helical structure 3. Enzyme involved in Transcriptiongiven by

5. Semi-conservative mode of 7. Site where the enzyme binds toDNA Replication given by start transcription.

2. Removal of Introns from RNA 8. Purine absent in DNA

6. Alec Jeffrey developed the 10. Factor necessary for Transcriptiontechnique to begin in prokaryots.

9. Change in the base pair 11. Lac operon is switched on in theSequence of DNA presence of inducer

4. Process of making polypeptidefrom RNA

(c) Label the Diagrams :–

(i)

1.

2.

3.

Nucleosome

(ii)

3´

5´

5´

3´

1.3.

Template Strand

4.

2.


Name ________________________ Roll No. _______

1. ________________________________________________________

2. ________________________________________________________

3. ________________________________________________________

4. ________________________________________________________

Name the Diagram – _______________________________________

Read the following passages and answers the questions :

(i) “Griffith observed that when heat killed S – Strain bacteria and line R –strain bacteria were mixed and injected into the mice, the mice died”.

(a) What is the name of the experiment which Griffith performed?

___________________________________________________

(b) Why did the mice died?

___________________________________________________

(ii) “For initiation, the ribosomes bind to the mRNA at the start coden, theribosomes proceeds to the elongation phase, the complexes composed ofamino acid linked to tRNA sequentially bind to the appropriate codon inmRNA by forming complementary base pair with tRNA. At the end releasefactor bind to tRNA and steps the process.”

(a) Which process is explained in the above stanza?

___________________________________________________

(b) What is the end product of this process?

___________________________________________________

(iii) “In the first step DNA is isolated and then digested by Restrictionendonuclease. The fragments are separated by electrophorosis and arethen transferred to nitrocellulose membrane where they are hybridisedusing VNTR probe which are visualized by Autoradiography.”

(a) Name the above mentioned process?

___________________________________________________

(b) Write two applications of this process?

___________________________________________________


Name ________________________ Roll No. _______

WORKSHEET

1. In a certain population, the frequency of three genotypes is as follows:Genotypes : BB, Bb, bb frequency : 22%, 62%, 16% (1)

2. Among the five factors that are known to affect Hardy – Weinbergequilibrium, three factors are gene flow, genetic drift and geneticrecombination. What are the other two factors. (1)

3. What is founder effect? (1)

4. Who among the Dryopithecus and Ramapithecus was more man-like?(1)

5. What is the most important pre-condition for adaptive radiation? (1)

6. It is said : “survival of the fittest”, does it mean that (2)

(a) those which are fit only survive, or

(b) those that survive are called fit?

Comment.

7. We are told that evolution is a continuing phenomenon for all living things.Are humans also evolving? Justify your answer. (2)

8. Distinguish between convergent and divergent evolution giving one exampleof each. (3)

9. Industrial Melanism in peppered moth is an excellent example of Naturalselection. Justify the statement. (3)

10. How do Darwin and Hugo de Vries after regarding Mechanism of Evolution?(5)


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WORKSHEET

1. Fill in the blanks. (1)

(a) The systematic study of fossils is called_______________

(b) _______________proposed that life comes from pre-existing life.

(c) _______________is the ancestor of modern amphibian.

(d) _______________is single step large mutation.

(e) Archaeoptryx is connecting link between _______________ and_______________

(f) Charles Darwin visited_______________islands.

2. Note the relationship between the first two words and suggest a suitableword for the fourth place.

(i) Flipper of whole : Wing of bird :: thorn of : ___________Bougainvillea

3. In a certain population, the frequency of three genotypes is as follows:(2)

Genotype BB Bb bb

Frequency 22% 62% 16%

What is the likely frequency of B and b alleles.

4. Name the five factors which affect Hardy Weinberg principle (5)


Name ________________________ Roll No. _______

WORKSHEET

1. The immune system of a person is suppressed. In the ELISA test, he wasfound positive to a pathogen.

a. Name the disease the patient is suffering from.

b. What is the causative organism? 1

2. What are interferons? 1

3. Breast fed babies are more immune to disease than the bottle fed babies.Why? 1

4. Name the pathogen which causes malignant malaria. 1

5. Which microorganism is used to produce hepatitis B Vaccine? 1

6. Where are B-cells and T-cells formed? How do they differ from each other?1

7. What is the role of histamine in inflammatory response? Name few drugswhich reduce the symptoms of allergy. 2

8. What are Cannabinoids? From which plant Cannabinoids are obtained?Which part of the body is affected by consuming these substances? 3

9. What is cancer? How is a cancer cell different from the normal cell? Howdo normal cells attain cancerous nature? 3

10. Represent schematically the life cycle of a malarial parasite. 5

OR

In your locality, if a person is addicted to alcohol, what kind of behaviouralchanges do you observe in that person? Suggest measures to over comethe problem.


Name ________________________ Roll No. _______

WORKSHEET

1. Write the names of Casual organisms of the following :–

(a) Typhoid (b) Pneumonia

(c) Elephantiasis (d) Amoebiasis (1)

2. Expand the following :–

(a) AIDS (b) ELISA

3. “Madhav suffered from measles at the age of 10 years. There are rarechances of his getting injected with the same disease for the rest of hislife”. Give reason for the statement.

4. When does a human body elicit an anamnestic response?

5. Name the diagnostic test which confirms typhoid.

6. Name the two major groups of cells required to attain specific immunity.

7. Which microorganism is used to produce hepatitis B vaccine?

8. “You have heard of many incidences of chickengunya in our country”.Name the vector of this disease.

9. Lymph nodes are secondary lymphoid organs. Describe the role of lymphnodes in our immune response.

10. What is source of :–

(a) Cocaine (b) Cannabinoids

11. In the given figure, structure of an antibody molecule is shown. Observeit and give the answer of the following questions :


Name ________________________ Roll No. _______

s-ss-s

s-s

s-s s-s

s-s

s-ss-s

s-s

ss

ss

C

B

A

s-s

(a) Label the parts A, B and C.

(b) Which cells produce these chemicals?

(c) State the function of these molecules.

12. In the given flow diagram, the replication of retrovirus in a host cell isshown. Examine it answer the following questions :

Retro virus

Viral RNA introduced into host cell

(1)

Viral genetue material in nucleus of the cell

Viral DNA incorporates into host genome

(2)

New viruses are produced.

Virus infects normal cells.

Reversetranscription


Name ________________________ Roll No. _______

(a) Why is virus called retrovirus?

(b) Fill in (1) and (2).

(c) Can infected cell survive while viruses are being replicated andreleased by host cell?

13. Kiran participated in a group discussion in her school on “The ill effects ofTobacco on Human Health”. In the evening, she goes with her family fordinner and insists on sitting in the “Non-Smoking Area” to which her father(a heavy smoker) objects.

(a) In this situation, who wins your support – Kiran’s concern for heath& environment or her father’s objection? Justify giving two reasons.

(b) Suggest any three effective propaganda compaigns for anti-tobaccoawareness.


Name ________________________ Roll No. _______

WORKSHEET

1. In animal husbandry, if two closely related animals are mated for a fewgenerations, it results in loss of fertility and vigour. Why is this so? 1

2. Name a man-made cereal? Trace how it was developed and where is itused? 1

3. A person who is allergic to pulses was advised to take capsule of Spirulinadaily. Give the reasons for the advice. 1

4. What is aquaculture? Give example of an animal that can be multiplied byaquaculture. 1

5. Name two fungal diseases of Crop plants. 1

6. A new breed of sheep was developed in Punjab by crossing two differentbreeds of Sheep. Name the two breeds which were crossed and the newbreed developed. 2

7. Differentiate between inbreeding and outbreeding in animals. 2

8. How is somatic hybrid different from a hybrid?

9. “Give me a living cell of any plant and I will give you a thousand plant ofthe same type” Is this only a slogan or is it scientifically possible? Writeyour comments and justify them. 3

10. You are a Botanist working in the area of plant breeding. Describe thevarious steps that you will undertake to release a new variety.


Name ________________________ Roll No. _______

WORKSHEET

1. Choose the correct option :

(i) Mule is produced by

(a) Selection (b) Inbreeding

(c) Interspecific hybridisation (d) Cross-breeding

(ii) Which is correctly matched?

(a) Apiculture – Honeybee (b) Pisciculture–Silk moth

(c) Sericulture – Fish (d) Aquaculture-Mosquitoes

(iii) The new varieties of plants are produced by :

(a) Selection and hybridisation (b) Mutation and selection

(c) Introduction and mutation (d) Selection and introduction

2. Fill in the blanks

(a) The crossing of F1 hybrid with either of the parents is knownas________________

(b) An organised mass of parenchymatous cells produced in a cultureis called________________

(c) For process of hybridisation, selfing of parents is done to reducethe________________

3. To which process of hybridisation, selfing of parents is done to reducethe_______________

(i) Crop plants (a) _____________

(ii) Fish production (b) _____________


Name ________________________ Roll No. _______

4. Study the flow chart given below : (2)

Cow is administered with FSH Hormone

(1)

6-8 eggs per cycle are produced

Artificially inseminated

Fertilised eggs at 8-32 cells are recovered

(2)

Identify (1) and (2)


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WORKSHEET

1. Why does ‘Swiss cheese’ have big holes? 1

2. Give any two microbes that are useful in biotechnology. 1

3. What is the source organism for EcoRI, restriction endonuclease?

4. An antibiotic called. Wonder Drug was used to treat the wounded soldiersof America during World War-II, Name the drug and the scientist whodiscovered it. 1

5. Name the plant whose sap is used in making Todday.. Mention the processinvolved in it. 1

6. Why are flows important in biological treatment of waste water? 2

7. How has the bacterium Bacillus thuringiensis helped us in controllingcaterpillars of inset pests? 2

8. What roles do enzymes play in detergents that we use for washing clothes?Are these enzymes produced from some unique microorganisms?

9. What is biochemical oxygen demand (BOD) test? At what stage of Sewagetreatment this test is performed? BOD level of three samples of waterlabelled as A, B and C are 30 mg/L, 10 mg/L and 500 mg/L respectively.Which sample of water is most polluted? 3

10. How does primary sludge differ from activated sludge? What type of changesin the sludge are carried out in anaerobic sludge digester? Give thecomposition of biogas produced in the sewage treatment plant. 5


Name ________________________ Roll No. _______

WORKSHEET

1. Complete the table : (2)

S.No. Molecule Source organism Use

(i) ____a____ Trichoderma polysparum Immuno suppressiveagent

(ii) Statin ____b____ Blood cholesterollowering agents

2. Identify a, b, c, d in the table (4)

S.No. Organic acid Microbe Type of microbe

(i) Citric acid ____a____ Fungi(ii) ____b____ Acetobactor aceti Bacteria(iii) Butyric acid Clostridium butylicum ____c____(iv) Lactic acid ____d____ Bacteria

3. Complete the table : (3)

S.No. Enzyme Uses

(i) a In detergent formulations(ii) Pectinases & Protease b(iii) c Clot buster

4. Name two free living nitrogen fixing microbes (1)


Name ________________________ Roll No. _______

WORKSHEET

1. A restriction enzyme digests DNA into fragments. Name the techniqueused to check the progression of this enzyme and separate DNA fragments.

1

2. Name two commonly used vectors in genetic engineering. 1

3. A linear DNA fragment and a plasmid has three restriction sites for EcoRI.How many fragments will be produced from linear DNA and plasmidrespectively? 1

4. What is the significance of adding proteases at the time of isolation ofgenetic material (DNA)? 1

5. While doing a PCR, ‘denaturation’ step is missed. What will be its effect onthe process?

6. A recombinant DNA molecule was created by ligating a gene to a plasmidvector. By mistake, an exonuclease was added to the tube containing therecombinant DNA. How does this affect the next step in the experiment i.e.bacterial transformation? 2

7. What would happen when once grows a recombinant bacterium in bio-reactor but forget to add antibiotic to the medium in which the recombinantis growing? 2

8. How will you obtain purified DNA from a cell? 3

9. A selectable marker is used in the section of recombinants on the basisof their ability to produce colour in presence of chromogenic substrate.

(a) Mention the name of mechanism involved.

(b) Which enyme is involved in production of colour?

(c) How is it advantageous over using antibiotic resistant gene as aselectable marker?


Name ________________________ Roll No. _______

10. The development of bio-reactors is required to produce large quantities ofproducts. 5

(a) Give optimum growth conditions used in bio-reactors.

(b) Draw a well labelled diagram of simple stirred tank bio-reactor.

(c) How does a simple stirred tank. Bio-reactor differ from spargedstirred tank bio-reactor?


Name ________________________ Roll No. _______

WORKSHEET

1. The technique used in making copies of a specific segment of DNA involves.(1)

(i) Ligase chain reaction (ii) Transcription

(iii) Polymerase chain reaction (iv) Translation

2. Name the first plasmid used as vector (1)

3. ____________are non coding sequences in eukaryotic DNA (1)

4. ____________technique is used in solving paternity disputes (1)

5. Give reason :– (2)

“To act as a vector, DNA molecule should bear origin of replication (Ori).

6. For producing a recombinant protein in large scale, which vector wouldyou choose – a low number or high copy number? Why? (2)

7. Identify (A) and (B) illustration in the following : (2)

G T T A A G–5´3´5´–G –3´

A

B

Plasmid


Name ________________________ Roll No. _______

WORKSHEET

1. Name two pest resistant plants produced by using recombinant DNAtechnology. 1

2. Name the technique based on the principle of antigen-antibody interactionused in detection of a virus (HIV). 1

3. Expand GMO. How is it different from a hybrid? 1

4. Name the first transgenic cow. Which gene was introduced in this cow? 15. For which variety of Indian rice, the patent was filed by a USA Company?

1

6. When a foreign DNA is introduced into an organism, how is it maintainedin the host and how is it transferred to the progency of the organism?

2

7. What are the two methods for correcting ADA deficiency in a child? 2

8. Some multinational companies and other organisations are usingbioresources for commercial benefits, without proper authentication andcompensation to concerned authorities.

(a) Give the term for this unauthorised act.

(b) Suggest any two ways to get rid of this. 3

9. A bacterium Bacillus thuringiensis produces a toxic protein named. cryprotein. That is lethal to certain insects but not to bacterium.

(a) Why this toxin does not skill the bacteria?

(b) What type of changes occur in the gut of insects on coming thisprotein?

(c) How man has exploited this protein for his benefit? 3

10. Highlight five areas where biotechnology has influenced our lives.


Name ________________________ Roll No. _______

WORKSHEET

1. Fill in the blanks

(a) Plants, bacteria, fungi and animals whose genes have been alteredby manipulation are called___________

(b) ___________toxin is produced by bacterium Bacillus thuringiensis.

(c) In GM plants, genetic modifications enchances___________valueof food.

(d) In insulin, chain A and B are linked by___________bridges

(e) ___________therapy is a collection of methods that allow correctionof a gene defect that has been diagnosed in child/embryo

(f) ___________mice are being used to test the safety of polio vaccine.

(g) Source of cry gene is___________

(h) ___________ was first transgenic cow

(i) ___________ is a circular extra-chromosomal DNA moleculepresent in the bacterial cell.

2. What is GEAC and what are its objectives? (3)

3. Expand GMO. How is it different from hybrid? (3)


Name ________________________ Roll No. _______

WORKSHEET

1. Fresh water animals are unable to survive for long in sea water. Give tworeason. 1

2. Define diapause. Which organisms exhibit it?

3. An organism has to overcome stressful condition for a limited period oftime. Which strategies can it adopt to do so? 1

4. Write what do phytophagous insects feed on? 1

5. What is commensalism? 1

6. Why do all the fresh water organisms have contractile vacuoles whereasmajority of marine organisms lack them? 2

7. Define heliophytes and sciophytes. Name a plant from your locality that iseither heliophyte or sciophyte. 2

8. How will you measure population density in following cases? 3

(i) Fish in a lake

(ii) tiger census in a national park

(iii) Single huge banyan tree with large canopy.

9. Species facing competition might evolve mechanism that promotescoexistence rather than exclusion. Justify this statement in light of Gausescompetitive exclusion principle, citing suitable examples. 3

10. Give one example for each of the following: 5

(i) Eurythermal plant species________________

(ii) A hot water spring organism______________

(iii) An organism seen in deep ocean trenches__________


Name ________________________ Roll No. _______

(iv) An organism seen in compost pit________________

(v) A parasitic angiosperm _______________

(vi) A stenothermal plant species____________

(vii) Soil organism____________

(viii) A benthic animal________________

(ix) Antifreeze compound seen in antarctic fish___________

(x) An organism which can conform


Name ________________________ Roll No. _______

WORKSHEET

1. What is meant by carrying capacity of the environment.

2. Between amphibians and birds, which will be able to cope with globalwarming? Why?

3. Species that tolerate wide range of salinity are called__________

4. What would be the growth rate pattern when the resources are unlimited?

5. What does sigmoid curve of a population indicate?

6. Complete the table

Species A Species B Name of Interaction

+ + Mutualism– – ---------------+ – ---------------+ 0 ---------------– 0 ---------------

7. Which plant/flower shows phenomena of “sexual deceit”?


Name ________________________ Roll No. _______

WORKSHEET

1. Arrange the following as observed in vertical stratification of a forest:1

2. Name an omnivore which occurs in both grazing food chain and thedecomposer food chain. 1

3. Who are generally the pioneer in a Xerarch succession and in a Hydrarchsuccession? 1

4. Which metabolic process causes a reduction in the Gross PrimaryProductivity? 1

5. What does the base tier of the ecological pyramid represent? 1

6. Differentiate between primary succession and secondary succession. Whichone occurs faster? 2

7. What is effect on decomposition rate if: 2

(a) Detritus is rich in lignin and chitin

(b) Detritus is rich is nitrogen and sugars

8. Name any four ecosystem services. Who gave the price tags on nature’slife support services? Which is the most important ecosystem serviceprovider? 3

9. What is an incomplete ecosystem? Explain with the help of suitable example.3

10. The biodiversity increase when one moves from the pioneer to the climaxstage. What could be the explanation?


Name ________________________ Roll No. _______

WORKSHEET

1. In an ecosystem dominated by trees, the pyramid (of number) is_______type(1)

2. Energy flow is an ecosystem is____________ (1)

3. A simplified model of phosphorous cycling in a terrestrial ecosystem isgiven below. Identify a, b, c, d

Consumer

Detritus

(d)Rock

Minerals

(c)

Rock Minerals

uptake run off

Litter fall

4. Fill in the missing stages in the given primary hydrastic succession (2)

Phyto plarkton A B C

Submergedfree floating

DForest stage


Name ________________________ Roll No. _______

WORKSHEET

1. What characteristics make a community stable? 1

2. What does ‘Red’ indicate in the IUCN Red list (2004)? 1

3. Define gene pool. 1

4. What is the reason for genetic variation shown by medicinal plant Rauwolfiavomitoria?

5. Explain co-extinction with a suitable example 1

6. Define cryopreservation. Why is it useful in conserving biodiversity? 2

7. Which region is considered as the one with highest biodiversity on earth?What is the name given to such region/forests? 2

8. Hot spots are the regions of exceptionally high biodiversity. But they havebecome regions of accidental habitat loss too. Name the three hot spotsof our country. Why are they called. Hot spot.? 3

9. Discuss one example, based on your day-to-day observations, showinghow loss of one species may lead to the extinction of another. 3

10. How can you, as an individual, prevent the loss of biodiversity? 5


Name ________________________ Roll No. _______

WORKSHEET

1. Fill in the blanks :–

(a) IUCN stands for________________

(b) First Earth summit was held at _________ and aimed at__________

2. Name the unlabelled areas ‘a’ and ‘b’ of the pie charts given belowrepresenting the biodiversity of invertibrate and vertebrate respectivelyshowing thin proportionate number of species of major terms.

Biodiversity of invertebrates

b Other animal groups

a

Crustaceans

Biodiversity of vertebrates

Mammals

Birds

Reptilesa

b

3. What is cryopreservation? (2)

4. What is Red data book? (2)


Name ________________________ Roll No. _______

WORKSHEET

1. Jhum cultivation has been in practice from earlier days, but its consideredmore problematic these days. Why? 1

2. A radiation causes ageing of skin, skin cancer, and inflammation of corneacalled snow blindness. It also damages DNA. Name the radiation.

1

3. What is the noise level that can cause permanent impairment of hearingability of human beings? 1

4. Use of lead-free petrol or diesel is recommended to reduce the pollutantemitted by automobiles. Why? 1

5. List any two adverse effects of particulate matter on human health. 1

6. Mention any two examples of plants used as wind breakers in the agriculturalfields. 2

7. Name an industry which can cause both air and thermal pollution and aswell as eutrophication. 2

8. Deforestation is creating a lot of problems in the environment. List theconsequences of deforestation. 3

9. Write a short note on electronic waste. List the various sources ofe-wastes and the problems associated with its disposal. 5.


Name ________________________ Roll No. _______

WORKSHEET

1. The figure given below shows the relative contribution of four greenhousegases to global warming.

B

C

D

A

(i) Identify A and C

(ii) Why are these 4 gases called as greenhouse gases? (2)

2. It is common practice to plant tree and shrubs near the boundary walls ofbuilding. What purpose do they serve? (2)

3. Suppose sewage water is disposed off in the river. Show its effect on BODand dissolved oxygen. (2)

4. What is difference between bad Ozone and good Ozone? (2)

Submitted by :

1. Alka Panwar (Lect. Biology)

2. B.C. Tiwari (Lect. Biology)

RPVV, Gandhi Nagar, New Delhi

3. Sita Ram Jangid (Lect. Biology)

GBSSS, Bindapur, Delhi

4. Sonia Gautam (Lect. Biology)

SKV, Gokal Puri

5. Hima Sood (Lect. Biology)

S.K. Kailash Enclave, Delhi

CLASS - XII

WORKSHEET - Delhi Directorate of Education · Identify each part in a flowering plant and write whether it is haploid (n) or diploid (2n) (5) ... of cell division occurs during these

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