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Questions:

Multiple Choice Question

50 x 1 = 50

Height in humans is

(a)

Somatagenic variation

(b)

Discontinuous variation

(c)

Continuous variation

(d)

Both B and C

Which plant in cultivated for about 7,500 years?

(a)

Oryza sativa

(b)

Triticum aestivum

(c)

Secale cerale

(d)

Chenopodium

If we uncover half of the forest covering the earth, what crisis will be produced at most and the first?

(a)

Some species will be extinct

(b)

Population and ecological imbalance will rise up

(c)

Energy crisis will occur

(d)

Rest half forests will maintain this imbalance

_____________ technique helps in identification of transformed cells in culture media.

(a)

Blue white colony selection

(b)

Antibiotic resistant markers

(c)

Replica plating

(d)

Agarose gel electrophoresis

In order to calculate map distance of genes on a chromosome, this has to be considered

(a)

Number of mutant genes

(b)

Cross over percentage

(c)

Recombination frequency of each gene locus

(d)

Non cross over percentage

An ovule which becomes curved so that the nucellus and embryo sac lie at right angles to the funicle is

(a)

camdylotropous

(b)

anatropous

(c)

orthotropous

(d)

hemianatropous

A scrubber in the exhaust of a chemical industrial plant removes

(a)

Gases like sulphur dioxide.

(b)

Particulate matter of the size 5 micrometer or above.

(c)

Gases like ozone and methane

(d)

Particulate matter of the size 2.5 micrometer or less

DB is a standard abbreviation used for the quantitative expression of

(a)

The density of bacteria in a medium

(b)

A particular pollutant

(c)

The dominant bacillus in a culture

(d)

A certain pesticide

This technique is used to diagnose the chromosomal abnormities.

(a)

Assisted Reproductive Technology (ART)

(b)

Micro Testicular Sperm Extraction

(c)

Amniocentesis

(d)

GIFT

10.

Multiple fission is seen in _______

(a)

Vorticella and ceratium

(b)

Plasmodium and paramecium

(c)

Amoeba and cyanobacteria

(d)

Vorticella and plasmodium

11.

B cells that produce and release large amounts of antibody are called

(a)

Memory cells

(b)

Basophils

(c)

Plasma cells

(d)

killer cells

12.

Anaphylactic shock is due to

(a)

Allergic reaction

(b)

Secretion of toxins

(c)

Secretion of histamines

(d)

All the above

13.

Find out the correctly matched pair.

(a)

Rubber-Shorea robusta

(b)

Dye-Lawsonia inermis

(c)

Timber-Cyperus papyrus

(d)

Pulp-Hevea brasiliensis

14.

Assertion: Vegetables are important part of healthy eating.
Reason: Vegetables are succulent structures of plants with pleasant aroma and flavours.

(a)

Assertion is correct, Reason is wrong

(b)

Assertion is wrong, Reason is correct

(c)

Both are correct and reason is the correct explanation for assertion.

(d)

Both are correct and reason is not the correct explanation for assertion.

15.

Match column I (crop) with column II (Corresponding disease resistant variety) and select the correct option from the given codes.

Column I	Column II
I) Cowpea	i) Himgiri
II) Wheat	ii) Pusa komal
III) Chilli	iii) Pusa Sadabahar
IV) Brassica	iv) Pusa Swarnim

(a)

I	II	III	IV
iv	iii	ii	i

(b)

I	II	III	IV
ii	i	iii	iv

(c)

I	II	III	IV
ii	iv	i	iii

(d)

I	II	III	IV
i	iii	iv	ii

16.

Match Column I with Column II

Column I	Column II
i) William S. Gaud	I) Heterosis
ii) Shull	II) Mutation breeding
iii) Cotton Mather	III) Green revolution
iv) Muller and Stadler	IV) Natural hybridization

(a)

i	ii	iii	iv
I	II	III	IV

(b)

i	ii	iii	iv
III	I	IV	II

(c)

i	ii	iii	iv
IV	II	I	IV

(d)

i	ii	iii	iv
II	IV	III	I

17.

Depletion of which gas in the atmosphere can lead to an increased incidence of skin cancer?

(a)

Ammonia

(b)

Methane

(c)

Nitrous oxide

(d)

Ozone

18.

Which of the following would most likely help to slow down the greenhouse effect.

(a)

Converting tropical forests into grazing land for cattle.

(b)

Ensuring that all excess paper packaging is buried to ashes.

(c)

Redesigning landfill dumps to allow methane to be collected.

(d)

Promoting the use of private rather than public transport.

19.

Which of the following are not regulating services of ecosystem services
i) Genetic resources
ii) Recreation and aesthetic values
iii) Invasion resistance
iv) Climatic regulation

(a)

i and iii

(b)

ii and iv

(c)

i and ii

(d)

i and iv

20.

Profundal zone is predominated by heterotrophs in a pond ecosystem, because of ______.

(a)

with effective light penetration

(b)

no effective light penetration

(c)

complete absence of light

(d)

a and b

21.

Predation and parasitism are which type of interactions?

(a)

(+,+)

(b)

(+, O)

(c)

(--, --)

(d)

(+, --)

22.

Which of the following plant has a non-succulent xerophytic and thick leathery leaves with waxy coating

(a)

Bryophyllum

(b)

Ruscus

(c)

Nerium

(d)

Calotropis

23.

Which of the given plant produces cardiac glycosides?

(a)

Calotropis

(b)

Acacia

(c)

Nepenthes

(d)

Utricularia

24.

SMOG is derived from:

(a)

Smoke

(b)

Fog

(c)

Both (a) and (b)

(d)

Only A

25.

Transgenic animals are those which have

(a)

Foreign DNA in some of their cells

(b)

Foreign DNA in all their cells

(c)

Foreign RNA in some of their cells

(d)

Foreign RNA in all their cells

26.

The genetic defect adenosine deaminase deficiency may be cured permanently by

(a)

Enzyme replacement therapy

(b)

periodic infusion of genetically engineered lymphocytes having ADA cDNA

(c)

administering adenosine deaminase activators

(d)

introducing bone marrow cells producing ADA into embryo at an early stage of development.

27.

Assertion(A): The Environmental conditions of the tropics are favourable for speciation and diversity of organisms.
Reason(R): The climate seasons, temperature, humidity and photoperiod are more or less stable and congenial.

(a)

Both Assertion and Reason are true and Reason explains Assertion correctly.

(b)

Both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

(c)

Assertion is true, but Reason is false.

(d)

Both Assertion and Reason are false.

28.

The gases produced in anaerobic sludge digesters are

(a)

Methane, oxygen and hydrogen sulphide

(b)

Hydrogen sulphide, methane and sulphur dioxide

(c)

Hydrogen sulphide, nitrogen and methane

(d)

Methane, hydrogen sulphide and CO₂.

29.

Cyclosporin – A is an immunosuppressive drug produced from _______

(a)

Aspergillus niger

(b)

Manascus purpureus

(c)

Penicillium notatum

(d)

Trichoderma polysporum

30.

The organization which published the red list of species is

(a)

WWF

(b)

IUCN

(c)

ZSI

(d)

UNEP

31.

Cryopreservation means it is a process to preserve plant cells, tissues or organs _____.

(a)

at very low temperature by using ether.

(b)

at very high temperature by using liquid nitrogen

(c)

at very low temperature of -196°C by using liquid nitrogen

(d)

at very low temperature by using liquid nitrogen

32.

Micro propagation involves _____.

(a)

vegetative multiplication of plants by using micro-organisms.

(b)

vegetative multiplication of plants by using small explants.

(c)

vegetative multiplication of plants by using microspores.

(d)

Non-vegetative multiplication of plants by using microspores and megaspores.

33.

Which period was called “Age of fishes”?

(a)

Permian

(b)

Triassic

(c)

Devonian

(d)

Ordovician

34.

Which of the following was the contribution of Hugo de Vries?

(a)

Theory of mutation

(b)

Theory of natural Selection

(c)

Theory of inheritance of acquired characters

(d)

Germplasm theory

35.

Select the incorrect action of hormonal contraceptive pills from the following

(a)

Inhibition of spermatogenesis.

(b)

Inhibition of ovulation

(c)

Changes in cervical mucus impairing its ability to allow passage and transport of sperms

(d)

Alteration in uterine endometrium to make it unsuitable for implantation

36.

Identify the correct statements from the following.

(a)

Chlamydiasis is a viral disease

(b)

Gonorrhoea is caused by a spirochaete bacterium, Treponema palladium

(c)

The incubation period for syphilis is 2 to 14 days in males and 7 to 21 days in females

(d)

Both syphilis and gonorrhoea are easily cured with antibiotics

37.

pBR 322, BR stands for ______.

(a)

Plasmid Bacterial Recombination

(b)

Plasmid Bacterial Replication

(c)

Plasmid Bolivar and Rodriguez

(d)

Plasmid Baltimore and Rodriguez

38.

E. coli cell grown on ¹⁵N medium are transferred to ¹⁴N medium and allowed to grow for two generations. DNA extracted from these cells is ultracentrifuged in a cesium chloride density gradient. What density distribution of DNA would you expect in this experiment?

(a)

One high and one low density band

(b)

One intermediate density band.

(c)

One high and one intermediate density band.

(d)

One low and one intermediate density band

39.

Hershey and Chase experiment with bacteriophage showed that ______.

(a)

Protein gets into the bacterial cells

(b)

DNA is the genetic material

(c)

DNA contains radioactive sulphur

(d)

Viruses undergo transformation

40.

The milk secreted by the mammary glands soon after child birth is called ______.

(a)

Mucous

(b)

Colostrum

(c)

Lactose

(d)

Sucrose

41.

The glandular accessory organ which produces the largest proportion of semen is ______.

(a)

Seminal vesicle

(b)

Bulbourethral gland

(c)

Prostate gland

(d)

Mucous gland

42.

The male sex hormone testosterone is secreted from _____.

(a)

Sertoli cells

(b)

Leydig cell

(c)

Epididymis

(d)

Prostate gland

43.

Allergy involves

(a)

IgE

(b)

IgG

(c)

lgA

(d)

IgM

44.

Amphetamines are stimulants of the CNS, whereas barbiturates are ______

(a)

CNS stimulant

(b)

both a and b

(c)

hallucinogenic

(d)

CNS depressants

45.

The mode of sexual reproduction in bacteria is by ______.

(a)

Formation of gametes

(b)

Endospore formation

(c)

Conjugation

(d)

Zoospore formation

46.

An allohexaploidy contains ______.

(a)

Six different genomes

(b)

Six copies of three different genomes

(c)

Two copies of three different genomes

(d)

Six copies of one genome

47.

What can be the blood group of offspring when both parents have AB blood group?

(a)

AB only

(b)

A, B and AB

(c)

A, B, AB and O

(d)

A and B only

48.

ABO blood group in man is controlled by _____.

(a)

Multiple alleles

(b)

Lethal genes

(c)

Sex linked genes

(d)

Y-linked genes

49.

Which one of the following is an example of polygenic inheritance?

(a)

Flower colour in Mirabilis Jalapa

(b)

Production of male honey bee

(c)

Pod shape in garden pea

(d)

Skin Colour in humans

50.

Pollen tube was discovered by ______.

(a)

J.G. Kolreuter

(b)

G.B. Amici

(c)

E. Strasburger

(d)

E. Hanning

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Answers Key:

Multiple Choice Question

50 x 1 = 50

(b)
Triticum aestivum

(a)
Some species will be extinct

(b)
Cross over percentage

(d)
hemianatropous

(a)
Gases like sulphur dioxide.

(b)
A particular pollutant

10.

(d)
Vorticella and plasmodium

11.

12.

(d)
All the above

13.

(b)
Dye-Lawsonia inermis

14.

(a)
Assertion is correct, Reason is wrong

15.

(b)

I II III IV

ii i iii iv

16.

(b)

i ii iii iv

III I IV II

17.

(d)
Ozone

18.

19.

20.

(b)
no effective light penetration

21.

(d)
(+, --)

22.

23.

(a)
Calotropis

24.

25.

(b)
Foreign DNA in all their cells

26.

(a)
Enzyme replacement therapy

27.

(a)
Both Assertion and Reason are true and Reason explains Assertion correctly.

28.

(d)
Methane, hydrogen sulphide and CO₂.

29.

(d)
Trichoderma polysporum

30.

(b)
IUCN

31.

32.

(b)
vegetative multiplication of plants by using small explants.

33.

34.

(a)
Theory of mutation

35.

(a)
Inhibition of spermatogenesis.

36.

(d)
Both syphilis and gonorrhoea are easily cured with antibiotics

37.

38.

(d)
One low and one intermediate density band

39.

(b)
DNA is the genetic material

40.

(b)
Colostrum

41.

(a)
Seminal vesicle

42.

(b)
Leydig cell

43.

(a)
IgE

44.

(d)
CNS depressants

45.

46.

47.

(b)
A, B and AB

48.

(a)
Multiple alleles

49.

(d)
Skin Colour in humans

50.

(b)
G.B. Amici

12th Standard Biology English Medium - Important 1 Mark MCQ's Question Paper and Answer Key 2022 - 2023

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