Question Set B

cbse 12th Standard Biology Human Reproduction Important Questions And Answers Study Material - QB365

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Questions:

Generic 2

24 x 2 = 48

Find out through internet and popular science articles whether animals other than man has self-consciousness.

(a) Plants are called as_______ because they fix carbon dioxide
(b) In an ecosystem, dominated by trees, the pyramid (of numbers) is_______ type.
(c) In aquatic ecosystems, the limiting factor for the productivity is_______
(d) Common detritivores in our ecosystems are_______
(e) The major reservoir of carbon on earth is_______

Name the bacterium responsible for the large holes in 'swiss cheese'. What are these holes due to?

What is the key difference between primary and secondary sewage treatment?

List the attributes that populations possess but not individuals.

How is copy number of the plasmid vector related to yield of recombinant protein?

Can you recall meiosis and indicate at what stage a recombinant DNA is made?

What are the various public health measures, which you would suggest as safeguard us against infectious diseases?

'It is possible that a species may occupy more than one trophic level in the same ecosystem time'.Explain with the help of an example.

10.

Most living organisms cannot survive at temperatures above 45 ^oC. How are some microbes able to live in habitats with temperatures exceeding 100^o C?

11.

Name any two techniques that serve the purpose of early diagnosis of some bacterial/viral human diseases.

12.

List the two main propositions of Oparin and Haldane.

13.

A student on a school trip started sneezing and wheezing soon after reaching the hill station for no explained reasons,But on return to the plains,the symtoms disappeared.What is such a response called?How does the body produce it?

14.

If the sequence of one coding strand of DNA is written as follows:
5' - ATGCATGCATGCATGCATGCATGCATGC -3'
write down the sequence of complementary strand in 5'⟶3' direction.

15.

If the base adenine constitutes 30 per cent of an isolated DNA fragment, then what is the expected percentage of the base cytosine in it?

16.

Which one out of an intron and an exon,is the reminiscent of antiquity?

17.

In order to obtain the F₁ generation, Mendel pollinated a pure-breeding tall plant with a pure-breeding dwarf plant. But, for getting the F₂ generation, he simply self-pollinated the tall F₁ plants. Why?

18.

A diploid organism is heterozygous for 4 loci, how many types of gametes can be produced?

19.

Is the use of contraceptives justified? Give reasons.

20.

Why are Copper-containing intrauterire devices considered an ideal contraceptive for human females?

21.

Define spermiogenesis and spermiation

22.

How many embryo sacs are formed in an ovule?

23.

Name the parts of an angiosperm flower in which development of male and female gametophyte takes place.

24.

Given below are the stages in human reproduction.Write them in the correct sequential order:
Insemination, Gametogenesis, Fertilisation, Parturition, Gestation, Implantation.

Multiple Choice Question

13 x 1 = 13

25.

Select the statement which explains best parasitism.

(a)

One organism is benefitted.

(b)

Both the organisms are benefitted

(c)

One organism is benefitted, other is not affected

(d)

One organism is benefitted, other is affected.

26.

Lichens are well known combination of an alga and a fungus where fungus has

(a)

an epiphytic relationship with the alga

(b)

a parasitic relationship with the alga

(c)

a symbiotic relationship with the alga

(d)

a saprophytic relationship with alga

27.

Which of the following walked like gorillas and chimpanzees?

(a)

Dryopithecus

(b)

Ramapithecus

(c)

Both (a) and (b)

(d)

Australopithecus

28.

Which of the following birth control measures can be considered as the safest?

(a)

the rhythm method

(b)

the use of physical barriers

(c)

termination of unwanted pregnancy

(d)

sterilization techniques

29.

In human beings, the eggs are:

(a)

Skin lecithal

(b)

Macrolecithal

(c)

Mesolecithal

(d)

Alecithal

30.

Heterozygous purple flower is crossed with recessive white flower. The progeny has the ratio :

(a)

75% purple and 25% white

(b)

50% purple and 50% white

(c)

All purple

(d)

All white

31.

Jumping genes given by Barbara Mclintock are also called

(a)

Transposons

(b)

Mutons

(c)

Cistrons

(d)

Vectors

32.

L.S.D, morphine and bhang are respectively obtained from

(a)

Claviceps, Papaver and Cannabis

(b)

Claviceps, Cannabis and Rauwolfia

(c)

Cannabis, Claviceps and Fuscarium

(d)

Claviceps, Rauwolfia and Papaver

33.

Egg apparatus consists of

(a)

egg

(b)

egg and polar nuclei

(c)

Egg and synergids

(d)

Egg and antipodal cells

34.

Human genome project was discovered by

(a)

Francis Collins and Roderick

(b)

Watson and Crick

(c)

Beadle and Tatum

(d)

Paul Berg and Wollman

35.

Which of the following is included in biopesticide?

(a)

Viruses and bacteria

(b)

Viruses, bacteria and fungi

(c)

Viruses, bacteria, fungi, protozoa and mites

(d)

Viruses, bacteria, fungi and protozoa

36.

Which one of the following has the largest population in a food chain?

(a)

Producers

(b)

Primary consumers

(c)

Secondary consumers

(d)

Decomposers

37.

Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselves because –

(a)

Bacteria are resistant to the toxin.

(b)

Toxin is immature.

(c)

Toxin is inactive.

(d)

bacteria enclose toxin in a special sac.

Fill up / 1 Marks

12 x 1 = 12

38.

Vertical distributioon of different species occupying different levels in an ecosystem, is called ________________.

39.

GM crops help to reduce the ______ losses.

40.

The __________ in a vector helps in identifying the transformants and eliminating the nontransformants.

41.

Alexander Fleming, Ernest Chain and _________were awarded Nobel Prize for the discovery of penicillin.

42.

_____ mosquitoes are the vectors of dengue and chikungunya.

43.

A study of fossils in different sedimentary layers indicates the ______ period in which they existed.

44.

If the sequence of the nitrogen bases in the coding strand of DNA is 5'- ATGAATT'-3', the sequence of bases in the RNA transcribed by it will be _____________.

45.

Trisomy of 21st chromosome in a male, leads to _____ syndrome.

46.

____ is the sterilisation procedure carried out in males.

47.

The stalk of the ovule is called___________.

48.

Humans are________(oviparous/viviparous/ovoviviparous)

49.

Species that can tolerate wide range of salinity are called ------------

True or False

11 x 1 = 11

50.

Natural or man-made distribances during succession, can convert a particular seral stage to an earlier stage.

(a)

True

(b)

False

51.

The disorder ADA deficiency can be cured by gene therapy only.

(a)

True

(b)

False

52.

Since DNA fragments are positively charged they move towards the anode.

(a)

True

(b)

False

53.

Trichoderma is a fungus used as a biocontrol agent.

(a)

True

(b)

False

54.

Humoral immunity is responsible for rejection of organ transplants

(a)

True

(b)

False

55.

Polycistronic mRNA is generaUy found in eukaryotes.

(a)

True

(b)

False

56.

The recessive trait appears only under homozygous condition.

(a)

True

(b)

False

57.

Contraceptive pills prevent ovulation and implantation.

(a)

True

(b)

False

58.

The finger-like projections, called fimbriae, help in the collection of ovum into the fallopian tube following ovulation.

(a)

True

(b)

False

59.

Sepals and petals or perianth are inconspicuous in entomophilous flowers.

(a)

True

(b)

False

60.

Ontogeny repeats phogeny.

(a)

True

(b)

False

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Answers Key:

Generic 2

24 x 2 = 48

Yes.
Many animals other than human have self-consciousness. For example, dolphins are highly intelligent. They have a sense of self and they also recognise others among themselves. They can communicate with each other by whistles, tail slapping, and other body movements. Besides dolphins some other animals such as parrots, chimpanzees, orangutans, gorilla, etc. are also found to have self-consciousness.

(a) autotrophs
(b) upright
(c) light
(d) earthworms and soil microbes.
(e) ocean

Propionibacterium sharmanii
1.Since this bacterium produces large amount of carbon dioxide during fermentatiom. large holes are produced.

Primary sewage treatment is a physical process and secondary treatment is a biological process.

Population attributes :
(i) Birth rate and death rate.
(ii) Age-Sex ratio.

()
The recombinant DNA can multiply as many times as the copy number of the plasmid vector. thereby determning the yield of recombinant protein So, higher the copy number of the plasmid vector, higher will be the yield of recombinant protein.

Diplotene of Prophase I.

Control of infectious diseases:
(i) Periodic cleaning and disinfection of water reservoirs, pools, tanks and observing standard practices of hygiene in public catering, for preventing those diseases that spread through food and water.
(ii) Consumption of clean drinking water, food, vegetables and fruits.
(iii) Many infectious diseases can be prevented by vaccination.
(iv) For vector-borne (mosquito is the vector) diseases, eradication/elimination of vectors and their breeding places could help in their control.

Yes, the trophic level of species represents the functional level of species in the energy flow. The preference of food habit depends on the available food. A single species may occupy more than one trophic level at the same time in ecosystem. For example, sparrow is primary consumer when it eats seeds and secondary consumer when feeds on insects and worms.

10.

They have a heat resistant protein.

11.

(i) Enzyme-linked immunosorbent assay (ELISA) test.
(ii) Polymerase chain Reaction (PCR)

12.

(i) The first form of life could have come from pre-existing non-living organic molecules like RNA, proteins, etc.
(ii) Formation of life was preceded by chemical evolution that resulted in the formation of diverse organic molecules from inorganic constituents.

13.

It is called allergy.

It is due to the release of histamine and serotonin by mast cells.

14.

The sequence of strand in 3' ⟶ 5' direction
3' - TACGTACGTACGTACGTACGTACGTACG - 5'
The sequence of strand in 5' ⟶ 3' direction
5' - AUGCAUGCAUGCAUGCAUGCAUGCAUGC - 3'

15.

According to Chargaff's rule,
A + G = C + T = 50%
if, A = 31% then, T =31%
C + T = 50%
C = 50% - 31% = 19%

16.

Intron is considered to be the reminiscent of antiquity because they were present even before splicing event. They might had important information to form RNA, but they do not serve any function.

17.

Characters segregate during gamete formation. Pure-breeding parents give rise to F₁ with heterozygous conditions. Only self-pollination of heterozygous can result in all possible recombinations of characters in progeny since the mating is random.

18.

The formula 2ⁿ is applied here
where, n = Number of loci
The organism is heterozygous for 4 loci, n =4
So, 2ⁿ= 2⁴ =2 x 2 x 2 x 2 = 16
The organism will produce 16 types of gametes.

19.

Use of contraceptives is justified due to the following reasons
(i) In the absence of contraceptives, the population growth rate will rise at an explosive rate and there will be scarcity of even the basic necessities.
Earth's resources are limited. We have already started facing the problems of overcrowding, food price inflation, power and water shortage, etc. Further increase in population will only aggrevate situation.
(ii) Contraceptives provide an option for planning the family by spacing the pregnancies and avoiding unwanted pregnancies.
(iii) Contraceptives also guard against STDs to some extent.

20.

Cut is an intra-uterine device (IUD) and functions as follows:
1. It suppresses sperm motility and the fertilising capacity of sperms.
2. It increases phagocytosis of sperms within the uterus.

21.

(i) Spermiogenesis is the process of transformation of spermatids into flagellated spermatozoa.
(ii) Spermiation is the process of release of spermatozoa from the seminiferous tubules.

22.

One

23.

1. Male gametophyte - In the Anther (microsporangia) and later on the stigma and style.
2. Female gametophyte - inside the ovule.

24.

Gametogenesis \(\rightarrow \) Insemination \(\rightarrow \) Fertilisation \(\rightarrow \) Implantation \(\rightarrow \) Gestation \(\rightarrow \) Parturition .

Multiple Choice Question

13 x 1 = 13

25.

(d)
One organism is benefitted, other is affected.

26.

27.

(a)
Dryopithecus

28.

(d)
sterilization techniques

29.

(d)
Alecithal

30.

(b)
50% purple and 50% white

31.

(a)
Transposons

32.

(a)
Claviceps, Papaver and Cannabis

33.

34.

(a)
Francis Collins and Roderick

35.

36.

(a)
Producers

37.

Fill up / 1 Marks

12 x 1 = 12

38.

()
Stratification.

39.

()
Post-harvest.

40.

()
Selectable marker.

41.

()
Howard Florey.

42.

()
Aedes.

43.

()
Geological.

44.

()
3' AUGAAUU 5'

45.

()
Down's.

46.

()
Vasectomy.

47.

()
Funicle.

48.

()
viviparous

49.

()
Euryhaline.

True or False

11 x 1 = 11

50.

(a)
True

51.

(b)
False

52.

(b)
False

53.

(a)
True

54.

(b)
False

55.

(b)
False

56.

(a)
True

57.

(a)
True

58.

(a)
True

59.

(b)
False

60.

(a)
True

cbse 12th Standard Biology Human Reproduction Important Questions And Answers Study Material - QB365 Set B

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Std: 12th Standard CBSE - Biology

chapter: Human Reproduction - Important Questions And Answers

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