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Higher Order Thinking Skills

Chapter Name of the Chapter:

No. 1 Reproduction in organisms. Region Tinsukia

Q 1 Rahul observed green coloured long algal filaments in a stagnant pond, which are single layer

aggregation of vertically arranged cells. What sort of strategy can this type of cellular aggregation

adopt for multiplication?

A Fragmentation (vegetative method).

Q 2 Both the prefixes ( Uni- and Mono- ) have the same meaning i.e. one in number. Does it mean

that uni-sexual and mono-ecious species are the same?

A Unisexual is used in reference to the flower (presence of either anther or carpel). Monoecious

is used in reference to the plant (morphologically one plant bearing both the sexes in their

flowers.

Q 3 In oogamy, female gamete is large and non-motile but the male gamete is reverse in its

properties. Why such type of adjustment is there in higher organisms?

A In oogamy, female gamete being larger and non motile, is an adaptation for having more food

reserves that may be required for the future development. The male gamete has to move to

reach the counterpart, so it has the machinery for its reaching and delivering the

chromosomes. A lot of cytoplasm will means extra weight also. So both the sex cells have

specialized themselves for their functions.

Q

4

Name organisms that reproduce to produce genetically similar individuals. What is the type of

reproduction do they follow? Why are the individuals so similar?

A Unicellular organisms. Asexual reproduction. Because they are morphologically and

genetically

identical.

Q

5

How do gemmules and gemma cup differ from each other?

A Gemmules are the internal buds found in coelenterates and sponges.

Gemmae are the external buds found in bryophytes.

Q 6 Fill in the blanks with their correct vegetative propagules:

a) Agave ---------------

b) Hydra----------------

c) Onion-----------

d) Mint------------

A a) Bulbil b) Buds c) Bulb d) Sucker

Q 7 In a pond ecosystem you may find the plant with purple flowers that spread very fast to cover

the entire pond within a short span of time. How does it spread? How does it harm the aquatic

body?

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A It is water hyacinth which reproduces by vegetative mean i.e. offset mean. It causes floods and

popularly known as `terror of Bengal`.

Q

8

In turkey there is no males found. Why? How is it possible? Give term for such type of

reproduction.

A It is parthenogenesis. In turkey diploid egg mother cell directly developed in to a female

zygote.

Q

9

It is found that in organisms like algae, fishes and amphibians gametes are produced in a large

number. Suggest a reason to support your answer.

A To enhance the chance of syngamy that occurs externally in water.

Q

10

In algae and fungi zygote would not undergone meiosis immediately, than what is its future?

A It develops a thick wall i. e. resistant against dessication and damage and undergone resting

before meiosis to pass out the unfavourable conditions.


No. 2 Sexual Reproduction in Flowering Plants Tinsukia Region

Q.1 Name the type of pollination that ensures genetic variation.

A Xenogamy

Q.2 The plant Yucca and moth cannot complete their life cycle without each other. Why?

A The moth deposits its eggs in locule of ovary and flower, in turn, gets pollinated by the moth.

Q.3 Give the other name of the following : pollen sacs , ovule , pollen grains ,embryo sacs.

A Micro sporangia, Mega sporangium, Microspores, Female gametophyte.

Q.4 In case of polyembryony, an embryo develops from the synergids and another from the

nucellus.

Which is haploid and which is diploid?

A Synergid embryo is haploid an nucellar embryo is diploid.

Q

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Q.6 Lable the following.



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No.3 Human Reproduction Tinsukia Region

Q What lead to menstruation in the absence of fertilisation?

A In the absence of fertilization, corpus luteum degenerates which causes disintegration of

endometrium leading to menstrual cycle.

Q Why not all copulations lead to fertilisation and pregnancy?

A Reason: fertilisation can only occur if the ovum and sperms are carried simultaneously.

Q A mother gets infected with a virus which causes German measles during pregnancy. Is it

possible that the foetus will also get infected? How ? What are its ill-effect on the foetus?

A



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A Yes, it is possible that the foetus gets infected. These viruses may diffuse through placenta. It

may cause malformations in the developing embryo.

Q How is the action of LH different in male and female?

A In male, LH is called ICSH (Interstitial cells stimulating hormone) which stimulates the leydig cells of the testis to secrete testosterone. In females, LH promotes ovulation and controls the

b) Morula.

c) In the inner cell mass.

d) The pole of the blastocyst that contains the inner cell mass.

Q The following illustration is the sequence of oogenesis in human female:

a) Mention the chromosome no. in a primary oocyte and a secondary oocyte

respectively.

b) When is meiosis II completed in the oogenesis of human female?

c) At what stage is meiosis I suspended in a primary oocyte?

A a) Primary oocyte=46; secondary oocyte=23.

b) It is completed during fertilisation.

c) Prophase I.

Chapter

No.4

Name of the Chapter:

Reproductive Health

Region

Guwahati

Q1 Why is CuT considered a good contraceptive device to space children?

A Cu suppress sperm motility , fertilizing capacity

formation of corpus luteum after ovulation. Q Study the figure given below and answer the question that follow:

a

a)Identify ‘a’ in the figure and mention its fuction. b)Mention the stage of human embryo it follows. c)Where are the stem cells located in this embryo? d) Which part of this stage of human embryo gets attached to endometrium to establish

pregnancy? A a) Inner cell mass. It forms the tissues of future embryo.



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Q.2 What is the significance of progesterone – estrogen combination as contraceptive measure?

A Easily available , create gap, inhibit ovulation and implantation, less side effect

Q3 What do you mean by ectopic pregnancy? Why does it happen?

A Implantation outside uterus, Due to STDs

Q.4 Give the difference between In – vivo and In –vitro fertilization.

A In-vivo (in side mother’s body), In- vitro (Inside the laboratory)

Q5 Why MTP?

A Medical termination of pregnancy – Population control, get rid of unwanted pregnancy, for health condition of mother and embryo

Chapter No.5 Name of the Chapter: PRINCIPLES OF

INHERITANCE AND VARIATION

KOLKATA

REGION

Q How will you find the genotype of an organism exhibiting a dominant phenotype trait ?

A By test cross ,with a homozygous recessive one .

Q What is the probability of Haemophilia in the son when a normal homozygous women is

married to a Haemophilic man ?

A 0 %

Q Show through a cross all the possibility of the genotypes of the progeny when a man with

blood

group B marries a women with blood group A, both heterozygous for the trait .

A Genotypes – IaIb , Ibi ,Iai , ii

Q What will be the karyotype of an individual who has developed from the zygote formed by

an XX

egg fertilized by a Y sperm ?Name the abnormality with which he will be suffering from .

A 47 chromosome , Klinefelter ‘s syndrome .

Q What will be the percentage of gametes ry , formed by an individual with genotype RrYy ?

A ry – 25% .

Q The distance between the two strands of DNA is maintained constant ? How it is

maintained ?

A By base pairing between the two strands that is adenine with thymine with two hydrogen bond

and guanine with cytosine with 3 hydrogen bond.

Q Fillin the blanks a , b, c and d :

TRAIT DOMINANT RECESSIVE

Seed shape a wrinkled

Flower position Axillary b

Pod shape c constricted



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A a -- round , b –terminal ,c -- inflated , d --yellow

Q What is the method of finding the genotype of an organism exhibiting a dominant phenotype

trait ? Explain.

A Test cross.In the cross ,if the individual is homozygous dominant ,all

the individuals in the progeny will be dominant. If the individual is

he and recessive trait in the ratio of 1:1.

terozygous, the progeny

will show both

dominant

Chapter

No.6


Molecular Basis Of Inheritance

KOLKATA REGION

Q It is found that in the Transcription process the DNA strand with 3’5’ is always transcribed

.Why ?

A As RNA polymerase can work only in 5’---> 3’ direction.

Q Where are UTRs located on m RNA ? Find out the UTRs from this segment of mRNA - 5’ UCG

AGC AUG CCC GCG UUU UAG GAG GAA 3’

A UTRs are present at both 5’-end (before start codon) and at 3’ –end (after stop codon). UCG,

AGC,GAG &GAA .

Q What is the importance of Lactose in Lac-Operon ?

A It induces Lac- Operon by binding with repressor protein.

Q What are the different attachment sites on t RNA ?

A Amino acid , anticodon ,enzyme and ribosome attachment sites .

Q Expand BAC and YAC . What for they are used ?

A BAC- Bacterial artificial chromosome , YAC- Yeast artificial chromosome .

Q What will happen if both template and coding strands of a DNA segment take part in the

transcription process ?

A If both the stands take part in transcription (1) one segment of DNA Would be coding for two

different proteins which will complicate the genetic information machinery. (2)Two RNA

molecules will be produced, complementary to each other, hence form a double stranded RNA.

Q Mention the two events when DNA is unzipped in a cell.

A Replication and Transcription

Q Name the chromosomes with highest and fewest number of genes .

A Chromosome 1 and Y chromosome .

Chapter

No.7


Evolution

Ranchi Region

Pod colour Green d



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(b) Dark and grey coloured moths on the bark of a tree in a polluted area.

Above picture shows industrial melanism. Prior to industrial revolution England had plenty of lichen flora on the bark of trees giving light coloured background suitable for white coloured moth but dark coloured moths were easily predated by the predators declining their numbers. After industrial revolution lichens disappeared from the tree barks which caused easy predation of white coloured moths than dark coloured declining the numbers of white moth in course of time.

Q1 What do these pictures (a) and (b) illustrate with reference to evolution?

A1 ( a ) Dark and grey coloured moths on the bark of a tree in an unpolluted area.



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Q2 On the basis of diagram given below explain the different ways of natural selection.

A2 Diagram explains three ways of natural selections which are-(a) Stabilising selection (b) Directional selection (c) Disruptive selection.

Q3 Define the terms-1.Germplasm 2.Branching descent.

A3 1. Germplasm - Protoplasm contained inside the germ cells that is transmitted from one

generation to other is called germplasm.

2. Branching descent-It the formation of different types of species from a common

ancestor due to variations and adaptations to varying ecological niches.

Q4 Write the formula to calculate allele frequency in future generations according to Hardy-

Weinberg equilibrium.

A4 (p + q)2 =p2+2pq+q2=1



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Q6 Give a flow chart to show the different divisions of geological time scale.

Q5 Give a comparison of the skulls of adult modern human being, baby chimpanzee and adult chimpanzee.

A5 The skull of a baby chimpanzee is more like adult human skull than adult chimpanzee skull.



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Note-Coenozoic era is divided in to two periods which are Tertiary and Quaternary and these are further divided into seven Epochs-1.Recent(Holozoic )1-0.6mya

2.Pleistocene 0.6-2.0mya

3.Pliocene 2-13mya

4.Miocene 13-26mya

5.Eocene 38-54mya

6.Palaeocene 54-65mya

Chapter No.8 Name of the Chapter:

Human Health & Diseases

Prepared

by: Ranchi

Region

Q Name the organ of our body that acts as a filter of blood & trap the blood born microbes.

A Spleen

Q Cancer causing genes are called ------------------------.

A Oncogenes

Q Which antibodies present in colostrum.

A IgA

Q Name the proteins secreted by virus infected cells which protects non-infected cells from

further

viral infection.

A6 Geological Time scale

Two major division

Cryptozoic Phanerozoic Era

Azoic ) Era of no life (

Archaeozoic Proterozoic Palaeozoic Mesozoic Coenozoic Era of invisible life Era of early life Era of ancient life Era medieval life Era of modern life

Cambrian Ordovician Silurian Devonian Carboniferous Permi an

Triassic Jurassic Cretaceous

Tertiary Quaternary



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A Interferons

Q Expand MALT.

A Mucosal Associated lymphoid Tissue

Q Cancer cells are more easily damaged by radiations than normal cells ,Why?

A Undergoing rapid division.

Q Name the medicine very effective sedative, pain killed & is very useful in patients who have

undergone surgery.

A Morphine

Q The chronic use of drugs & alcohol damages nervous system and liver, this is known as -------

-----.

A Cirrhosis

Q What do you mean by withdrawal syndrome?

A When the regular dose of drugs /alcohol is abruptly discontinued ,the body to manifest an

unpleasant syndrome characterised by anxiety, shakiness, nausea & sweating

Q What c-onc or proto-onc genes?

A Cellular onco genes or proto onco genes are present in normal cells which ,when activated

under

certain conditions,could lead to oncogenic transformation of the cells.

Q Name the scientist who discovered the life cycle of malarial parasite.

A Sir Ronald Ross.

Q which type of organisms cause ringworm.

A Fungi

Q Name the disease caused due to abnormal increase in lymphocytes of blood.

A Leukemia/Blood cancer

Q Against which diseases does the MMR vaccine give protection ?

A Measels,Mums&Rubeolla


No.09 Strategies for enhancement in food production Ranchi Region

Q How does mutation breeding artificially occur in plants?

A Chemicals and gamma radiations

Q Name the varieties of rice from which sem-dwarf variety have been developed.

A IR-8

Q What is meant by micro-propagation?

A Methods of producing plants by tissue culture.

Q What are the disease resistence varities of Brassica and wheat?

A Brassica-Pusa swarnim ,Wheat-Himgiri

Q Name the Indian scientist,whose efforts brought ‘green revolution’ in India.

A M.S. Swaminathan

Q Write down the difference between pisciculture and aquaculture.



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A Pisciculture is the method of culture of fishes.Aquaculture is the culture of aquatic animals.

Q How does MOET help in cattle breeding?

A Successful production of hybrids are high, the herd size increased in a short time.

Q The Indian Agricultral Research has released several varieties of crop plants.Name the three

plants with their biofortification.

A Vit-A enriched carrot and spinach,protein enriched beans,Vitamin-C enriched bittergourd and

mustard.

Q How are somaclones cultured from explants in in-vitro? Why are somaclones so called?

A Somaclones can be cultured from explants in a test tube under sterile conditions in nutrient

medium.

Q Give an example where mutation breeding has been successfully carried for disease

resistance.

A Abelmoschus esculentus(bhindi)

Q

Fill in the blanks:a,b and c.

Crop Variety Insect pest

Brassica(Rapeseed mustard) a Aphids

b Pusa sem 2 Jssids,aphids and fruit borer

Pusa sem 3

Okra(Bhindi) Pusa sawani, c

Pusa A-4

A a-Pusa gaurav,b-Flat bean,c-Shoot and fruit borer.

Chapter

No. 10 Name of the Chapter: MICROBES

IN HUMAN WELFARE

SILCHAR Region

A1 A. Head B. Collar C. Tail D. Plate E. Pins F. Prongs



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A5 Merits : Enhance the quality & quantity of crops, less requirement of insecticide & pesticides, improve agronomic characteristics. Demerits : Favors new pathogen strain , dependability of farmers on biogenic companies.


No.11 BIOTECHNOLOGY & ITS PRINCIPLES BHUBANESWAR Region

Q

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.

Q2 As Saccharomyces cerevisiae produces CO2 during fermentation, if fermented dough of

Aspergillus niger is used to make bread, then what happens on its consumption ?

A2 Food will produce toxicity because Aspergillus niger produce aflatoxins.

Q3 Raman underwent kidney transplantation after which he observed allergic reactions. Can you

suggest the name of microbial product and its source for controlling them.

A3 Product : cyclosporine A, Source : Trichoderma polysporum (fungi)

Q4 Swati knows that the cow excreta contains a specific bacteria. Name the type of bacteria and

how it can be socially used.

A4 Methanogens (Archebacteria), Social use: lightening & cooking by using gobar gas.

Q5 GM crops are favored by some countries, while in India it is still banned. Can you suggest merits

and demerits of such crops ?

A

B C D

E F



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A

Q2.

Answer the questions from the figure given

i) W rite the name of the enzyme required for PCR.

ii) From which organism it is obtained?

Q1. Label the parts in the figure



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A i)Taq polymrrase

ii)Thermus aquaticus iii) Thermostable

Q3. Match the following

A B

i) Bacteria i) Celluase

ii) Chitinase ii)Microparticles of gold or tungsten coated with DNA

iii) Plant cell iii) Microinjection

iv) Recombinant DNA injected

to nucleus of an animal cell iv) Lysozyme

v) Biolistic /Gene gun v) Fungus

A Match the following

A B

Bacteria --- ---------------------- Lysozyme

Chitinase --------------------- Fungus

Biolistic /Gene gun ----------- Microparticles of gold or tungsten coated

with DNA

Plant cell ---------------------

Recombinant DNA injected to

Celluase

nucleus of an animal cell ------ ------ Microinjection

Q4. Write the pallinodromic sequence of the following

5’ ----- GAATTC------- 3’

A 3 ‘ ------ CTTAAG---- 5’

Q5

i)What dose the fig shows?

ii)What is the matrix used for the above process?

Iii)Name the chemical compound used for staining?

iv)Name the process for the separation of DNA from the

agarose gel.

Iii) What is the significance of this enzyme ?



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A i) Agarose gel electrophoresis ii) Agarose

iii) Ethidium bromide iv) Elution


No.12 BIOTECHNOLOGY &ITS APPLICATION BHUBANESWAR Region

Q1. I) Expand GMO . What are the uses of G.M. Pants ?

A Genetically Modified Organism.

a)It tolerates abiotic stresses such as cold ,drought salt & heat.

ii)It reduces reliance / dependence on chemical pesticides iii) It reduces post harvest loses. iv) It increases efficiency of mineral utilization by plants. v)Enhances nutritional value of food

Q2. Match the following

A B

i) Bt toxin i) Human alpha lactalbumin

ii) CryIAc& cryIIAb ii)Emphysema

iii) CryIAb iii) Bacillus thuringiensis

iv) α-1 –antitrypsin iv) Corn borer

v) Produce of transgenic cow Rosie v) cotton bollworms

A i) Bt toxin --- --------------------------------- ----Bacillus thuringiensis ii) CryIAc& cryIIAb---------------------------- -----Cotton bollworms iii) CryIAb -------------

------------------------------- Corn borer iv) α-1 –antitrypsin ---------------------

------------Emphysema

v) Produce of transgenic cow Rosie ------------ Human alpha lactalbumin



18 HOTS

Q3. Give one word

i)Supply of alternative resources to industries

In the form of starches fuels & pharmaceuticals.

ii New strategy adopted to protect the tobacco

Plant infestation by Meloidogyne incognitia.

iii)Technique based on the principle of

antigen antibody interaction.

A

i)Supply of alternative resources to industries in the form of starches fuels & pharmaceuticals. i)Tailor-made plants

ii New strategy adopted to protect the tobacco

plant infestation by Meloidogyne incognitia ii)RNA interference

iii)Technique based on the principle of

antigen antibody interaction iii) ELISA

iv)Uses of bioresources by multinational companies /other organization whitout proper authorization from the concerned parties

iv)Biopiracy

v) Decision making organization regardingvalidity of

G.M. resources & the safety of introducing G.M. crops v)GEAC

Q4. Draw the diagram showing maturation of proinsulin to mature Insulin.

iv)Uses of bioresources by multinational companies /other organization

Without proper authorization from the concerned parties.

vi) Decision making organization regardingvalidity of G.M. resources & the safety of

introducing G.M. crops.



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A

Q5 Differentiate between the insulin produce by rDNA & insulin produce by pancreas.

A

rDNA Insulin produced by pancreas

i) It is produced artificialy i) It is produced naturally

ii) It produces only A & B polypeptides ii)It has three

polypeptides

A,B& C before maturation


Organisms and Populations

Region Guwahati

Q1 Why are green plants not found beyond a certain depth in the ocean?

A As light is not available

Q.2 When does a population growth curve assume J – shaped?

A Unlimited resource in the habitat

Q3 When and Where will you found pseudo copulation?

A Similarities between female bee and orchid.

Q.4 What helps the fishes to survive in different water conditions?

A Osmoregulation

Q5 Explain Gause’s Competitive exclusion Principle.



20 HOTS

A Co

existence

and elimination of two closely related species


Ecosystem

Region Guwahati

Q1 ‘Stability of ecosystem depends on complexity of food web. ‘Justify the statement.

A Diversity of food chain, more than one option in their food habit

Q.2 ‘GPP – R = NPP ‘ What do you understand by the given equation?

A Gross primary productivity , Respiration , Net primary productivity.

Q3 What are eco system services? Why Robert Constanza Put a price tags on nature’s life- support

services?

A Product of ecosystem and it’s usefulness.

Q.4 Differentiate between – (a) Primary and Secondary succession ( b ) Pyramid of energy and

Pyramid of biomass

A (a) Slower and Faster ( b) Upright and Inverted

Q5 Explain Hydrarch succession in detail. How it is different from Xerarch succession?

A Various stages of development. Succession in dry areas.

Q6 Carbon cycle plays an important role in the biosphere. Discuss

A Diagram with explanation.


No. 15 Biodiversity and conservation

Silchar Region

Q 1 Alien species are threat to native species. Justify

A Alien species are species that have been introduced from another geographic region to an area outside its natural range. For example;- Parthenium, Lantana and Eicchornia are invaded the native species of India and causes environmental damage. Introduction of African catfish Clarias gariepinus in India for aquaculture purpose is posing threat to many indigenous catfish.

Q 2 The species diversity of plants (22%) is much less than that of animals (70%). What could

be the explanation to how animals achieved greater diversification?



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A As plants could not move away from their predators and harsh environmental conditions, many of them have become extinct. Animals can move away from harmful environment and their predators and survive better and so more diversity.

Q 3 Species extinction is accelerating at a fast speed mainly due to human activities. Group

such activities under four major heads and explain.

A Habitat loss and fragmentation; over exploitation; Alien Species invasions and co-extinctions.

Q 4 Why is the number of prokaryotic species not yet estimated till now?

A Conventional taxonomic methods are not suitable for the identification of prokaryotic species.

Q 5 Who are the Ecologists associated with the following works:

(i) The sociologist who popularized the term Biodiversity

(ii) Developed the River Popper hypothesis.

(iii) Gave the estimate of global species diversity

(iv) Performed experiments to show that increased diversity contributed to higher

productivity

A Edward Wilson; Paul Ehrlich; Alexander von Humboldt; Robert May; David Tilman

Q 6 Human activities had lead to progression of Sixth extinction at a faster rate than the previous five

episodes of extinction. How does the sixth extinction differ from the previous episodes of

extinction?

A The rate of sixth episode of extinction is progressing 100 to 1000 times faster than the previous episodes of extinction.

Q 7 If we apply May’s global estimates of species in Indian context, how many species of animal have

been recorded?

A About 90000.


No.16 Environmental issues

Region silchar

Q 1 Why does biomagnifications occur with certain substances ?name two such substances.

A Biomagnifications is the phenomenon in which harmful chemicals get accumulated in the tissues



22 HOTS

metabolized nor excreated;instead it accumulates in the tissues of the organisms.

ii)biomagnification

A

three.what is the reason?

i)enhanced bitumen’s water repellant property,and helped to increase road life by a factor of

three.

Q 4 Through auto fuel policy,Euro II norms,the government of india has laid out a road map to cut

down the vehicular air pollution in many cities of india.what this norms stipulated?

A Euro II norms stipulates that sulphur be controlled at 350 ppm in diesel and 150 ppm in petrol.aromatic hydrocarbons are to be contained at 42 percent of the concerned fuel.according to the road map,is to reduce sulphur to 50ppm in petrol and diesel and bring down the level to 35 percent.

Q 3 Blends of polybend and bitumen , when used, help to increase the life of roads by a factor of

of organism in increasing concentrations at successive trophic levels.DDT and mercury. Q 2 Study the given aquatic food chain and answer the question that follow:

i)Give reasons why there is a continuous increase in the DDT content in different trophic levels of the chain. ii) Name the phenomenon responsible for the increase in DDT content.

A i) the concentration of DDT increases at successive trophic levels because it is neither

Fish eating birds ( DDT 5 ppm )

Large fish ( DDT 2 ppm )

Small fish

( ) DDT 0.5 ppm

Zooplankton

DDT 0.04 ppm ( )

water

0.003 ( DDT ppm)



23 HOTS

Q

5

The figure shows the relative contribution of four greenhouse gases to global

warming.

i) Identify the gases A and C.

ii) Why are these four gases called the greenhouse gases?

A i) A-carbon dioxide ,C-CFCs

ii) The molecules of these gases radiate heat energy, and a major part of which again comes to earth’s surface,thus heating it up once again,results green house effect.



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