VIKASH EDUCATIONAL INSTITUTIONS VIKASH RESIDENTIAL …odishavikash.com/VRS_Bargarh/HA/SUMMER...

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VIKASH EDUCATIONAL INSTITUTIONS

VIKASH RESIDENTIAL SCHOOL, BARGARH SUMMER VACATION ASSIGNMENT FOR CLASS-XII

1. REPRODUCTION IN ORGANISMS

ONE MARK QUESTIONS:

1. Name the phase all organisms have to pass through before they can reproduce sexually.

2. . Name an organism where cell divisionin itself is a mode of reproduction.

3. Name the vegetative propagules in following

a) Agave b) Bryophyllum

4. How many chromosomes do drones of Honeybee posses ? Name the type of cell division

involved in the production of sperms by them.

5. A male honeybee has 16 chromosomes where as its female has 32 chromosome. Give one

reason.

6. Banana is a true fruit as well as a parthenocarpic fruit, Give reason.

7. Why is banana considered a good example of parthenocarpic?

TWO MARKS QUESTIONS:

8. The cell division involved in gamete formation is not of the same type in different

organisms. Justify.

9. Why do moss plants produce very large number of male gametes? Provide one reason.

What are these gametes called?

10. A single pea plant in your kitchen garden produces pods with viable seeds but the

individual papaya plant does not. Explain.

THREE MARK QUESTION:

11. a) State the type of gametes shown in the diagram.

b) Identify the process taking place and the resultant structure.

c) Name an organism that reproduces in this manner.

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12. Distinguish between asexual and sexual reproduction. Why is vegetative reproduction also

considered as a type of asexual reproduction? How will an organism be benefitted, if it

reproduces through spores?

2. SEXUAL REPRODUCTION IN FLOWERING PLANT

ONE MARK QUESTIONS:

1. State the purpose for carrying emasculation in breeding experiments.

2. An anther with malfunctioning tapetum often fails to produce viable male gametophytes.

Give one reason.


3. State one advantage and one disadvantage of cleistogamy.

4. In angiosperms, zygote is diploid while primary endosperm cell is triploid. Explain.

5. Gynaceum of a flower may be apocarpous or syncarpous . explain with the help of an

example each.

6. During an excavation assignment, scientists collected pollen grains of a plant preserved

in deeper layers of soil. Analyse the properties of pollen grains which help in the

fossilization.


7. Explain the function of each of the following:

a) Coleorhiza

b) Umbillical cord

c) Germ pore

8. Make a list of any three outbreeding devices that flowering plants have developed and

explain how they help to encourage cross-pollination.

9. Why are angiosperm anthers called dithecous? Describe the structure of its

microsporangium.

10. State what is apomixis. Comment on its significance. How can it be commercially used ?

11. . A non biology person is quite shocked to know that apple is a false fruit, mango is a true

fruit and banana is a seedless fruit. As a biology student how would you satisfy this

person ?

12. Describe the development of endosperm after double fertilization in an angiosperm.

Why does endosperm development preceeds that of zygote?

13. Name the organic material exine of the pollen grain is made up of. How is this

material advantageous to pollen grain?

Still it is observed that it does not form a continuous layer around the pollen grain.

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Give reason.

How are ‘pollen banks’ useful?

14. A) How are Parthenocarpic fruits produced by some plants and apomictic seeds by

some others? Explain.

b) When do farmers prefer using apomictic seeds?

15. Draw and label the enlarged view of microsporangium. State the function of its innermost

layer.

16. Trace the development of a megaspore mother cell into a fully developed embryo sac.

17. Draw a diagram of a mature embryo sac of an angiosperm and lable the following

part in it.

i) Filiform apparatus ii ) Synergids iii) Central cell

iv) Egg cell v) Polar nuclei vi) Antipodal

FIVE MARKS QUESTIONS:

18.

i) Most zygotes in angiosperms divide only after certain amount of endosperm is

formed

ii) Groundnut seeds are exalbumious and castor seeds are albuminous.

iii) Micropyle remains as a small pore in the seed coat of a seed.

iv) Integuments of an ovule harden and the water content is highly reduced, as the

seed matures.

v) Apple and cashew are not called true fruits.

19.

a) Draw a labeled diagram of L.S. of an embryo of grass (any six labels).

b) Give reason for each of the following:

I) Anthers of angiosperm flowers are described as dithecous.

II) Hybrid seeds have to be produced year after year.

20. Why is fertilisation in an angiosperm referred to as double fertilisation? Mention the

ploidy of the cells involved.

Draw a neat labelled sketch of l.s of an endospermous monocot.

21. Draw a diagrammatic sectional view of a mature anatropous ovule and label the

following parts in it:

i) That develops into seed coat.

ii) That develops into an embryo after fertilization.

iii) That developes into an endosperm in albuminous seed.

iv) Through which the pollen tube gains entry into the embryo sac.

v) That attaches the ovule to placenta.

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22. A)draw an L.S. of a pistil showing pollen tube entering the embryo-sac in an angiosperm

and label any six parts other than stigma, style and ovary.

B) write the changes a fertilized ovule undergoes within the ovary in an angiosperm

plant.

23. a) explain the different ways apomictic seeds can develop. Give an example of each.

b) Mention one advantage of apomictic seeds to farmers.

c) draw a labelled mature stage of a dicotyledonous embryo.

24. a) Plan an experiment and prepare a flow chart of the steps that you would follow to ensure

that the seeds are formed only from the desired sets of pollen grains. Name the type of experimen

that you carried out.

b) write the importance of such experiments.

25. A flower ofbrinjal plant following the process of sexual reproduction produces 360 viable

seeds.

a) How many ovules are minimum involved?

b) How many megaspore mother cells are involved?

c) What is the minimum number of pollen grain that must land on stigma for pollination ?

d) How many male gametes are involved in the above case?

e) How many microspore mother cell must have undergone reduction division prior to

dehiscence of anther in the above case?

26. Answer the following questions:

(a) Draw a diagram of an enlarged view of L.S. of one microsporangium of an angiosperm and

label the following parts.

i. Tapetum

ii. Middle layer

iii. Endothecium

iv. Microspore mother cells.

(b) Mention the characteristic features and function of tapetum.

(c) Why pollen grains are well preserved as fossils?

(d) What are two factors that affect the viability of the pollen grain?

27. Answer the following questions regarding seed:

(a) What are the advantages offered by seed to angiosperm?

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(b) What is crucial for storage of matt seed?

(c) Which is the oldest viable seed and how old is it? Write the scientific name of the

plant.

(d) Write the scientific name of 2000 years old viable seed recently discovered during

archeological at King Herod’s palace near Dead Sea

3. HUMAN REPRODUCTION

ONE MARK QUESTIONS:

1. Name the embryonic stage that gets implanted in the uterine wall of a human female.

2. Where is acrosome present in humans ? write its function.


3. a) where do the signals for parturition originate from in humans ?

b) why is important to feed the newborn babies on colostrum?

4. a) The human testes are located outside the abdominal cavity.

b) Some organism like honey-bees are called parthenogenetic animals.

5. Write the location and functions of the following in human testes.

a.Sertoli cells

b.Leydig cells

6. Why are the testes of human males considered extra-abdominal? What is the significance

of this condition?

7. What is the colostrum ? Why is it important to be given to the new born infants?

8. . Meiosis and gamete formation are two universal events take place in all sexually

reproducing organisms. Timing of meiosis is different in different organism: Justify your

answer with suitable example.


9. Draw a diagram of the microscopic structure of human sperm. Label the following parts

in it and write their functions.

a) Acrosome

b) Nucleus

c) Middle piece

10. Name the stage of human embryo at which it gets implanted. Explain the process of

implantation.

11. . Describe the process of Parturition in humans.

12. Draw a labeled diagram of the reproductive system in a human female.

13. a) Which hormones are responsible for parturition?

b) Draw labeled diagram of a blastocyst.

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c) Mention the site of fertilization; describe how zygote develops and when it attaches to

uterus?

14. a) Draw well labeled diagram of a human sperm.

b) What will happen if the acrosome of a sperm is removed?

15. Observe the diagram given below and answer the following questions.

i. Label the parts ‘A’, ‘B’, ‘D’ and ‘E’.

ii. What you call to the milk produced during the initial few days of

lactation? it essential for the baby?

FIVE MARKS QUESTIONS

16. The following is the illustration of the sequence of ovarian events ‘a’ to ‘I’ in a human

female’:

a) Identify the figure that illustrates corpus luteum and name the pituitary hormone that

influences its formation.

b) Specify the endocrine function of corpus lueteum. How does it influence the uterus?

Why is it essential?

c) What is the difference between ‘d’ and ‘e’?

d) Draw a neat labeled sketch of graffian follicle.

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17. Draw a diagrammatic sectional view of the female reproductive system of human and

label the parts

i) Where the secondary oocyte develop

ii) Which help in collection of ovum after ovulation

iii) Where fertilization occurs

iv) Where implantation of embryo occurs.

v)

Explain the role of pituitary and the ovarian hormones in menstrual cycle in human

females.

18. A)draw a diagramatic sectional view of human seminiferous tubule, and label sertoli

cells, primary spermatocyte, spermatogonium and spermatozoa in it.

B)Expain the hormonal regulation of the process of spermatogenesis in humans?

19. a) where does fertilization takes place in humans? Explain the events that occur during

this process.

B) a couple where both husband and wife are producing functional gametes, but the wife

is still unable to conceive, is seeking medical aid. Describe any one ,method that you can

suggest to this couple to become happy parents.

20. describe the roles of pituitary and ovarian hormones during the menstrual cycle in a

human female.

21. Human female is not fertile after menopause whereas males can produce gametes at any

age after puberty. Analyse the statement and schematically represent a comparison

between gametogenesis in males and females.

22. Give the termlreasons:-

a) Mechanism responsible for parturition.

. b) Role of oxytocin during expulsion of the baby out of uterus.

c) Why does zona pellucid layer block the entry of additional sperms?

d) Sperm cannot reach ovum without seminal plasma.

e) AU copulation do not lead to fertilisation and pregnancy

23. Draw a neat diagram of female reproductive system and label the parts associated with

the following:

(i) Production of gamete (ii) Site of fertilisation (iii) Site of implantation (iv) Birth canal.

24. a) Describe in detail the events taking place during oogenesis.

b) When does meiotic division complete in the ovum?

25.

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a) Compare the fate of sperms shown in the diagram.

b) What is the role of zona pellucida in this process?

c) Analyze the changes occurring in the ovum during the process.

d) Mention what helps in the entry of sperm into the ovum.

e) Specify the region of female reproductive system where the event represented in the diagram

takes place.

4. REPRODUCTIVE HEALTH

ONE MARK QUESTIONS:

1. Govt. of India has raised the marriageable age of female to 18 yrs and of males to 21 yrs.

Suggest any two more measures adopted by Government for the purpose.

2. In case of an infertile couple, the male partner can inseminate normally but the mobility of

sperms is below 40 percent. Judge, which kind of ART is suitable in this situation to form an

embryo in the laboratory, without involving a donor?

3. Mention one advantage and one disadvantage of natural method of contraception.

4. In case of an infertile couple, the male partner can inseminate normally but the mobility of

sperms is below 40 percent. Judge, which kind of ART is suited in this situation to form an

embryo in the laboratory, without involving a donor?


5. Describe the Lactational Amenorrhea method of birth control.

6. After a brief medical examination a healthy couple came to know that both of them are

unable to produce functional gametes and should look for an ‘ART’ (Assisted Reproductive

Technique). Name the ‘ART’ and the procedure involved that you can suggest to them to

help them bear a child.

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7. An infertile couple is advised to adopt test-tube baby programme. Describe two principle

procedures adopted for such technologies.

8. i) Name any two copper releasing IUDs,

ii) Explain how they act as effective contraceptives in human females.


9. A woman has certain queries as listed below, before starting with contraceptives?

A) What do contraceptive pills contain and how do they act as contraceptives ?

B) What schedule should be followed for taking these pills?

10. Mention the problems that are taken care of by Reproduction and Child Health Care

programme. What is amniocentesis and why there is a statutory ban on it?

11. Name two hormones that are constituents of contraceptive pills. Why do they have high and

effective contraceptive value? Name a commonly prescribed non-steroidal oral pill.

FIVE MARK QUESTION:

12. A village health worker was taking a session with women. She tells the women that one has

to be very careful while using oral pills as method of birth control. Wrong usage can actually

promote conception.

(a) Analyze the statement and compare the merits and demerits of using oral pills and

surgical methods of birth control.

(b) Village women were confused as to how a thin metallic Copper loop can provide

protection against pregnancy. Justify the use explaining the mode of action of IUDs.

13. What is ART? Suggest any four methods to assist the infertile couple to have children.

14. a) Tubectomy and Vasectomy cannot be considered as methods of contraception. Give

reason.

b) How techniques like GIFT, ZIFT, AI are different from each other? Describe each one of

them.

c) Under which conditions will a couple need surrogate mother’s help?

5. PRINCIPLES OF INHERITANCE AND VARIATION

ONE MARK QUESTIONS:

1. A garden pea plants produced axial white flowers. Another of the same species produced

terminal violet flowers. Identify the dominant traits.

2. Observe the pedigree chart and answer the following questions:

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(a) Identify whether the trait is sex-linked or autosomal.

(b) Give an example of a disease in human beings which shows such a pattern of inheritance.

3. Give an example of a chromosomal disorder caused due to non-disjunction of autosomes.

4. A human being suffering from Down’s syndrome shows trisomy of 21st chromosome.

Mention the cause of this chromosomal abnormality.

5. If two genes are located far apart from each other on a chromosome, what will be its

effect on the frequency of recombination?


6. The gene I that controls the ABO blood grouping in human beings has three alleles IA, IB

and IC. and i.

(a) How many different genotypes are likely to be present in the human population?

(b) How many phenotypes are possibly present?

7. If two genes are closely linked on a chromosome, how the frequency of recombination

will get affected?

8. A cross between a red flower bearing plant and a white flower bearing plant of

Antirrhinum produced all plants having pink flower work out a cross to explain how this

is possible.

9. Write the scientific name of the fruit-fly. Why did morgan prefer to work with fruit-flies

for his experiments? State any three reasons.

10. Linkage and crossing over of genes are alternatives of each other. Justify with the help of

an example.

11. In snapdragon, a cross between true-breeding red flowered (RR) plants and true-breeding

white flowered (rr) plants showed a progeny of plants with all pink flowers.

a) The appearance of pink flower is not known as blending. Why?

b) What is this phenomenon known as?

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12. . Explain mechanism of sex-determination in birds.

13. Differentiate between ‘ZZ’ and ‘XY’ type of sex-determination mechanisms.

14. Why is pedigree analysis done in humans? List two reasons why the Mendelian

experiments cannot be carried out in human beings.

15. Study the figures given below and answer the question

Identify in which of the crosses is the strength of linkage between the genes higher. Give

reasons in support of your answer.

16. Both Down’s syndrome and Turner’s syndrome are examples of chromosomal

disorders. Cite the differences between the two.

17. Name the genetic disorder caused by trisomy of 21 chromosomes in humans. Write the

diagnostic feature of the disorder.

18. In dogs, black coat colour is dominant over white. What coloured dog will you choose to

breed with a given black dog, in order to find its genotype? What is this type of cross

known as?

19. . Both Down’s syndrome and Turner’s syndrome are examples of chromosomal

disorders. Cite the differences between the two.


20. A) Explain the phenomena of multiple allelism and co-dominance taking ABO blood

group as an example

b) What is the phenotype of the following?

I) IAi (ii) ii

21. A) Why is human ABO blood group gene considered a good example of multiple

alleles?

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b) Work

out a cross

up to F1

generation only: between a mother with blood group A(Homozygous) and the father with

blood group B (Homozygous). Explain the pattern of inheritance exhibitted.

13.

22. Why is pedigree analysis done in the study of human genetics? State the conclusions that

can be drawn from it.

23. During a monohybrid cross involving a tall pea plant with a dwarf pea plant, the offspring

populations were tall and dwarf in equal ratio. Work out a cross to show how it is

possible.

24. . A teacher wants his/her students to find the genotype of pea plants bearing purple

25. coloured flowers in their school garden. Name and explain the cross that will make it

possible.

26. What is a test cross? How can it decipher the heterozygosity of a plant?

27. a) What is a test cross? How is it useful to the geneticist?

b) Write the genotype and phenotype of progenies formed by a cross between a

homozygous tall plant and a heterozygous tall plant.

OR

Describe male heterogamety and female homogamety through two suitable examples.

28. How are Dominance, Co-Dominance, Incomplete Dominance, patterns of inheritance

different from each other?

OR

Haemophitia is a sex-linked recessive disorder of human. The pedigree chart given below

shows the inheritance of haemophilia in a family. Study the pattern of inheritance and

answer the questions given.

NO. Syndrome cause Characteristics of

affected individuals

Sex

Male/Female/Both

1. Down’s Trisomy

of 21

‘ A’I)

ii)

‘B’

2. c XXY Overall masculine

Development

‘D’

3. Turner’s 45 with

XO

‘E’ I)

II)

‘F’

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(i)Give all the possible genotypes of the members numbered 4,5 and 6 in pedigree chart.

(ii) A blood test shows that the individual 14 is a carrier of haemophilia. The member

numbered 15 has recently married the member numbered 14. What is the possibility that

their first child will be a haemophilic male?

29. A cross is made between different homozygous pea plants for contrasting flower colours.

a) Find out the colours of flowers in F1 generation on the basis of genotypes.

b) Work out the cross upto F2 generation.

c) Compute the relative fraction of various genotypes in the F2 generation?

30. Examine the pedigree chart given below and answer the questions. (3)

31.

(a). Is the trait being studied in the pedigree recessive or dominant? How do you know?

(b) Is the trait being studied in the pedigree sex-linked recessive? Justify your answer?

(c) What is the likely genotype of II-4 for the trait being studied in the pedigree?

32. Study the figures given below and answer the question.

i. Identify in which of the crosses is the strength of linkage between the

genes higher. Give reasons in support of your answer.

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ii. Write the two conditions in which independent assortment will take place

between two pairs of genes.

33. In garden pea, smooth seed coat is dominant over wrinkled seed coat. What will be the

expected ratio of phenotypes of the offspring in a cross between:

(a) Heterozygous smooth X Heterozygous smooth

(b) Heterozygous smooth X Homozygous wrinkled

(c) Heterozygous smooth X Homozygous smooth

34. What is chromosomal basis of Turner’s syndrome? Mention the sex and any three

symptoms of this disorder.

FIVE MARKS QUESTIONS:

35. Explain a monohybrid cross taking seed coat colour as a trait in Psium sativum. Work out

the cross upto F2 generation.

State the laws of inheritance that can be derived from such a cross.

How is the phenotypic ratio of F2 generation different in a sihybrid cross?

36. Describe the mechanism pattern of inheritance of ABO bllod groups in humans.

37. a) Why haemophilia is generally observed in human males? Explain the conditions under

which a human female can be haemophilic.

b) A pregnant human female was advised to undergo M.T.P. It was diagnosed by her

doctor that the foetus she is carrying has developed from a zygote formed by an XX-egg

fertilized by Y-carrying sperm. Why was she advised to undergo M.T.P.?

38. A child suffering from Thalassemia is born to a normal couple. But the mother is being

blamed by the family for delivering a sick baby.

a) What is Thalassemia?

b) How would you counsel the family not to blame the mother for delivering a child

suffering from this disease? Explain.

c) List the values your councelling can propagate in the families.

39. A child suffering from Thalassemia is born to a normal couple. But the mother is being

blamed by the family for delivering a sick baby.

d) What is Thalassemia?

e) How would you counsel the family not to blame the mother for delivering a child

suffering from this disease? Explain.

f) List the values your councelling can propagate in the families.

40. Work out a typical Mendelian dihybrid cross and state the law that he derived from it.

41. a) why are colourblindness and thalassemia categorised as Mendelian disorders? Write

the symptoms of these diseases seen in people suffering from them.

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C) About 8% of human male population suffers from colourblndness whereas only about

0-4% of human female ppulation suffers from this disease. Write an explanation to

show how it is possible.

42. a) What are pleiotropic genes? Give example.

b) Describe the inheritance pattern of human skin colour.

c) Differentiate between co dominance and incomplete dominance.

MOLECULAR BASIS OF INHERITANCE

ONE MARK QUESTIONS

1. Mention the contribution of genetic maps in HGP.

2. Why is it not possible for an alien DNA become part of a chromosomes any where along

its length and replicate normally?

3. Retroviruses have no DNA. However the DNA of the infected host cell does posseas

viral DNA. How is it possible?

4. What is a cistron.

5. Writre Erwin chargaff’s observation with respect to DNA molecule structure.

6. Name the type of chemical bond formed between two nucleotide units of a DNA

molecule?

TWO MARKS QUESTIONS

7. Name the bond between the pentose sugar and the nitrogen base. To which carbon of the

pentose sugar does the nitrogen base bind?

8. Calculate the length of the DNA of bacteriophage lambda that has 50000 base pairs.

9. Write the full form of VNTR. How is VNTR different from ‘Probe’?

10. a) Draw a neat labeled diagram of a nucleosome.

b) Mention what enables histones to acquire a positive charge.

11. State the difference between the structural genes in transcription unit of Prokaryotes and

Eukaryotes.

12. Following are the features of genetic codes. What does each one indicate? Stop codon,

unambiguous codon, degenerate codon, universal codon.

13. What is aminoacylation? State its significance.

14. Name the cells HIV gains entry into after infecting the human body. Explain the events

that occur in these cells.

15. Differentiate between euchromatin and heterochromatin.

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16. Protein synthesis machinery revolves around RNA but in the course of evolution it was

replaced by DNA. Justify.

THREE MARK QUESTION

17. I) Name the enzyme that catalyses the transcription of hnRNA.

II) Why does the hnRNA need to undergo changes? List the changes hnRNA undergoes

and where in the cell such changes take place.

18. Unambiguous, universal and degenerate are some of the terms used for the genetic code.

Explain the salient fearures of each one of them.

19. List the salient features of double helix structure of DNA.

20. How are the structural genes activated in the lac operon in E.coli?

21. Describe the structure of a RNA polynucleotide chain having four different types of

nucleotides.

22. Explain the significance of satellite DNA in DNA fingerprinting technique.

23. a) A DNA segment has a total of 1,500 nucleotides, out of which 410 are Guanine

Containing nucleotides. How many pyrimidine bases this segment possesses?

(b) Draw a diagrammatic sketch of a portion of DNA segment to support your answer.

24. Following the collision of two trains a large number of passengers are killed. A majority

of them are beyond recognition. Authorities want to hand over the dead to their relatives.

Name a modern scientific method and write the procedure that would help in the

identification of kinship.

25. What do ‘Y’ and ‘B’ stand for in ‘YAC’ and ‘BAC’ used in Human Genome

Project (HGP). Mention their role in the project.

Write the percentage of the total human genome that codes for proteins and the

percentage of discovered genes whose functions are known as observed during

HGP.

Expand ‘SNPs’ identified by scientists in HGP.

26. Write the missing steps in the flow chart below of RNAi in proper sequence

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27. “There is a paternity dispute for a child.” Which technique can solve the problem?

Discuss the principle involved

28. Study the following and answer the questions that follows: (C.= codon, A = amino acid,

Hb = Hemoglobin)

i. Why mutation ‘A’ does not produce abnormal hemoglobin? Which property of

genetic code works here?

ii. What you call to the type of mutation that produce sickle cell hemoglobin due to

mutation ‘B’.

iii. Write any one other property of genetic code.

29. (a) Why does DNA replication occur in small replication forks and not in its entire

length?

(b) Why is DNA replication continuous and discontinuous in a replicating fork?

(c) Explain the importance of ‘origin of replication’ in a replication fork.

30. A policeman finds a very small body tissue from the site of a crime and takes it to the

forensic department.

I . By which technique will they amplify the DNA collected from the tissue sample?

II . Explain the each step involved in this cycle.

lII. Write the role of thermostable DNA polymerase enzyme.

31. A DNA segment has a total of 1500 nucleotides out of which 410 are Guanine containing

nucleotides. How many pyrimidine bases this DNA segment possesses.

OR

Given below is a schematic representation of lac-operon:

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a) Identify I and p.

b) Name the inducer for this operon and explain its role.


32. Describe frederick Griffith’s experiment on Streptococcus pneumoniae. Discuss the

conclusion he arrived at.

33. A) Write the conclusion drawn by Griffith at the end of his experiment with

Streptococcus pneumoniae.

B) How did O.Avery, C.Macleod and M.McCarty prove that DNA was the genetic

material? Explain.

34. Describe the hershey and chase experiment. Write the conclusion drawn by the scientists

after their experiment.

35. explain the process of transcription in prokaryotes. How is the process different in

eukaryotes?

36. 36. Observe the representation of genes involved in the lac operon given below

P i P O Z y a

(a) Identify the region where the repressor protein will attach normally.

(b) Under certain conditions repressor is unable to attach at this site. Explain.

(c) If repressor fails to attach to the said site what products will be formed by z, y and a?

(d) Analyze why this kind of regulation is called negative regulation.

37. Transcription in eukaryotes is more complex process than in prokaryotes. Justify and

compare the initiation, elongation and termination in bacterial cells with eukaryotes.

38. Answer the following questions based on Meselson and Stahl's experiment:-

a) Write the name of chemical used as a source of Nitrogen in the experiment.

b)Why did scientist synthesise the light and heavy DNA molecule?

c)How did the scientists make it possible to distinguish the heavy DNA

molecules from the light DNA molecules? Explain.

a) Write the conclusion drawn by them at the end of their experiment.

39. tRNA is charged with the amino acid methionine ..

I) At what site in the ribosome will the tRNA bind?

II) Give the anticodon of this tRNA.

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III) What is the mRNA codon for methionine?

IV) Name the enzyme responsible for this binding.

V) Why tRNA is known as adapter molecule.

40. Who proposed that DNA replication is semi- conservative? How was it experimentally

proved by Meselson and Stahl?

41. What is transcription? Describe the process of transcription in Eukaryotes. Support your

answer with suitable diagram.

42. Explain the process of protein synthesis from processed m-RNA.

43. Distinguish between Leading strand and Lagging strand? Explain DNA replication with

the help of the labelled diagram of Replication Fork. How is Okazaki fragments are

joined together?


(a) What is this diagram representing?

(b) Name the parts a, b and c.

(c) Name two acids rich in ‘a’.

(d) How many base pairs present in each unit‘d’

(e) What is the role of non-histone protein in packaging of DNA?

45. Answer the following question from the diagram given below:

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A) Identify the polarity from a to a’ in the diagram and mention how many more amino

acids are expected to be added to this polypeptide chain.

B) Mention the DNA sequence coding for serine and the anticodon of the tRNA for the

same amino acid.

C) Why are some untranslated sequences of bases seen in mRNA coding for a

polypeptide? Where exactly are they present in the mRNA?

D) To which site the amino-acyl- tRNA present in the larger sub-unit of ribosome?

E) Name the enzyme that forms the peptide bond between the amino acids during

protein synthesis.

46. Two blood samples, A and B picked up from the crime scene, were handed over to the

forensic department for genetic fingerprinting. Describe how the technique of genetic

fingerprinting is carried out. How will it confirmed whether the samples belonged to the

same individual or to two different individuals?

EVOLUTION

ONE MARK QUESTIONS

1. Name the common ancestor of the great apes and man.

2. Comment on the similarity between the wing of a cockroach and the wing of a bird.

What do you infer the abvove, with reference to evolution.

3. Why are analogous structures a result of convergent evolution

4. Write the probable differences in eating habit of Homo habilis and Homo erectus.

5. State what is a change in allele frequency in a sample of new population indicative of

?

6. Who among the Dryopithecus and Ramapithecus was more man like?

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TWO MARKS QUESTIONS

7. List the two main propositions of oparin and Haldane.

8. (a) Select the homologous structures from the combinations given below :

(i) Forelimbs of whales and bats

(ii) Tuber of potato and sweet potato

(iii) Eyes of octopus and mammals

(iv) Thorns of Bougainvillea and tendrils of Cucurbita

(b) State the kind of evolution they represent.

9. How does theory of panspermia explain origin of life?


(a) Anthropogenic actions have caused evolution of species. Explain with the help of

two examples.

(b) Differentiate between divergent and convergent evolution.

THREE MARK QUESTION

11. Branching descent and natural selection are the two key concepts of Darwinian

Theory of Evolution. Explain each concept with the the help of a suitable example.

12. How does industrial melanism support Darwin’s theory of Natural Selection?

Explain.

13. With the help of any two suitable examples explain the effect of anthropogenic

actions on organic evolution.

14. What does the following equation represent? Explain.

p2 + 2 pq + q2 = 1

15. What is adaptive radiation? When can adaptive radiation be referred to as convergent

evolution? Give an example.

16. Explain the interpretation of Charles Darwin when he observed a variety of

smallblack birds on Galapagos Islands.

17. Differentiate between homology and analogy. Give one example of each.

18. Explain the three types of natural selection along with their prescribed graphs.

19. Diagrammatically represent the Miller’s Experimental set up. Whose hypothesis was

proved by him?

20. Refer to the figure given below and answer the questions that follow:

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a) Recognize and explain the process by which Tasmanian wolf evolved.

b) Give one example of an animal that has evolved along with Tasmanian wolf.

c) Compare and contrast the two animals shown?

21. Diagramatically represent the experimental set up that proves Oparin – Haldane

hypothesis.

(a) Mention the specific geographical region where these organisms are found.

(b) Name and explain the phenomenon that has resulted in the evolution of such diverse

species in the region.

(c) Explain giving reasons the existence of placental wolf and Tasmanian wolf sharing the

same habitat.

22. A population is exhibiting genetic equilibrium. Answer the following with regard to

this statement.

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i) Explain the above statement.

ii) Name the underlying principle.

iii) Name any four factors which could upset the genetic equilibrium of the population.

HUMAN HEALTH AND DISEASE

ONE MARK QUESTIONS

1. State two different roles of spleen in the human body.

2. Why is secondary immune response more intense than the primary immune

response in humans?

3. Thymus of a new born child was degenerating right from birth due to a genetic

disorder. Predict its two impacts on the health of the child.

4. Name the drugs obtained from Cannbis sativa.

5. State a method of cellular defense which works in all eukaryotic organisms.

6. State a method of cellular defence which works in all eukaryotic organisms.

TWO MARKS QUESTIONS

7. Differentiate between benign and malignant tumors.

8. Name the plant source of ganja. How does it affect the body abuser?

9. Name the two special types of lymphocytes in humans. How do they differ in

their roles in immune response ?

10. Name the bacterium that causes typhoid. Mention two diagnostic symptoms. How

is this disease transmitted to others?

11. Write the events that take place when a vaccine for any disease is introduced into

the human body.

12. Why a person with cuts and bruises following an accident is administered tetanus

antitoxin? Give reasons.

13. List the symptoms of Ascariasis. How does a healthy person acquire this

infection.

14. A patient showed symptoms of sustained high fever, stomach pain and

constipation but no blood clot in stools, Name the disease and its pathogen. Write

the diagnostic test tor the disease How does the disease get transmitted.

15. What are interferons? How do they help in developing resistance to infection?

16. . Explain metastasis. Why is it fatal?

THREE MARK QUESTION

17. I) Write the scientific names of the two species of filarial worms causing

filariasis.

ii) How do they affect the body of infected persons?

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ii) how does the disease spread?

18. Trace the life-cycle of malarial parasite in the human body when bitten by an

infected female Anopheles.

19. Explain mutalism with the help of any two examples. How is it different from

commensalism?

20. Community service department of your school plan a visit to a slum area near the

school with an objective to educate the slum dwellers with respect to health and

hygiene

a) Why is there a need to organize such visit?

b) Write the step you will highlight, as a member of this department, in your

intraction with them to enable them to lead a healthy life.

21. A heavily bleeding and bruised road accident victim was brought to a nursing

home. The doctor immediately gave him an injection to protect him against a

deadly disease.

(a) Write what did the doctor inject into the patient’s body.

(b) How do you think this injection would protect the patient against the disease?

(c) Name the disease against which this injection was given and the kind of immunity

it provides.

22. A team of students are preparing to participate in the interschool sports meet.

During a practice session you find some vials with labels of certain

cannabionoids.

(a) Will you report to the authorities? Why?

(b) Name a plant from which such chemicals are obtained.

(c) Write the effect of these chemicals on human body.

23. It is generally observed that the children who had suffered from

Chicken - pox in their childhood may not contract the same disease in their

adulthood. Explain giving reasons the basis of such an immunity in an

individual. Name this kind of immunity. What are interferons? Mention their

roles.

24. Write the source and effect of following :

a) Smack b) Cocaine c) LSD

OR

a) What are autoimmune diseases? Name any two.

b) What is basis for vaccination in human beings? Write the full form of DPT vaccine.

25. What is active and passive immunity? Give examples of vaccines that provide

active and passive immunity. Mention which one is long lasting and why?

26. a.What is Metastasis ?

b. Differentiate between Benign and Malignant tumours.

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27. Your classmate complains of headache and cough to the doctor. The doctor

confirms that he is suffering from Pneumonia and not just common cold. How the

doctor must have reached to such conclusion? Mention any two precautions to be

followed to prevent the spread of this disease.

28. A doctor prescribed morphine as a sedative and pain killer to your cousin who has

undergone surgery. Even after recovery he continued to consume the prescribed

medicine. What do you conclude about his condition? After appraising yourself,

what measures will you suggest to him to control this problem? Briefly explain

any two.

29. Your classmate complains of headache and cough to the doctor. The doctor

confirms that he is suffering from Pneumonia and not just cold. How the doctor

must have reached to such conclusion? Mention any two precautions to be

followed to prevent the spread of this disease.

30. Refer to the diagram given below and answer the question that follow

i) The parasite reproduces in human host by which method?

ii) The sexual stages of parasite are referred to as?

iii) Where does the fertilisation and development of parasite takes place in mosquito

both?

IV) What are sprozoites?

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31. Describe the asexual and sexual phases of life cycle of Plasmodium that causes

malaria in humans.

32. A person in your colony has recently been diagnosed with AIDS. People in the

colony want him to leave the colony for the fear of spread of AIDS.

b) Write your view on the situation, giving reasons.

c) List the possible preventive measures that you would suggest to the residents of your

locality in a meting organised by you so that they underestand the situation.

D) Write the symptoms and the causative agent of AIDS.

33.

A)Define central dogma. How retroviruses are an exception to the unidirectional

information flow?

B) Describe the steps involved in life cycle of the AIDS virus.

34. Observe the diagram given below and answer the questions followed:

(a) What does the above diagram illustrate?. .

(b) Name the part labeled ‘A’, ‘D’, ‘E’ and ‘C’.

(c) Name the cell that produces this molecule. .

(d) What you call to the type of immunity produced by this molecule?

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Study the diagram showing replication of HIV in humans and answer the

following questions accordingly:

(a) Write the chemical nature of the coat ‘A’.

(b) Identify the ‘X’. .

(c) Name the enzyme ‘B’ acting on ‘X’ to produce molecule ‘C’. Name ‘C’.

(d) Mention the name of the host ‘D’ the HIV first when it enters into the human

body. . . .

(e) Name the two different cells the new viruses ‘E’ subsequently attack.

VIKASH EDUCATIONAL INSTITUTIONS VIKASH RESIDENTIAL …odishavikash.com/VRS_Bargarh/HA/SUMMER...

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