Genes and Chromosomes Test 6

Total Questions:50 Total Time: 60 Min

Remaining:

 

Questions 1 of 50

Question:Two sister chromatids are attached with the:

Answers Choices:

Spindle fibres

Chromatid

Centromere

Chromocentre

Questions 2 of 50

Question:Different types of chromosomes can be recognized by the position of the following separating the two arms:

Answers Choices:

Nucleus

Spindle

Gene

Centromere

Questions 3 of 50

Question:The structure of the chromosome to which spindle fibre attached is:

Answers Choices:

Centromere

Chromatid

Chromonema

Chromomere

Questions 4 of 50

Question:Which one can have sex chromosomes?

Answers Choices:

Hermaphrodite plant

Unisexual plant

Bisexual flower

Unisexual flower

Questions 5 of 50

Question:Kinetochore is:

Answers Choices:

end of chromosome

surface of centromere

granule within centromere

constriction near chromosome end

Questions 6 of 50

Question:Plant in which chromosomal basis of sex determination was discovered is:

Answers Choices:

Coccinia

Sphaerocarpus

Rumex

Melandrium

Questions 7 of 50

Question:Nucleosome core is made of:

Answers Choices:

\({H_1},{H_2}A,{H_2}B\,\,and\,\,{H_3}\)

\({H_1},{H_2}A,{H_2}B\,\,and\,\,{H_4}\)

\({H_1},{H_2}A,{H_2}B,{H_3}\,\,and\,\,{H_4}\)

\({H_2}A,{H_2}B,{H_3}\,\,and\,\,{H_4}\)

Questions 8 of 50

Question:Polytene chromosomes were seen by:

Answers Choices:

Heitz

Balbiani

Wilson

Ruckert

Questions 9 of 50

Question:The polytene chromosomes were discovered for the first time in:

Answers Choices:

Chironomus

Fruitfly

Housefly

Mosquito

Questions 10 of 50

Question:Episome may be a factor in:

Answers Choices:

chromosomal inheritance

cytoplasmic inheritance

incomplete dominance

codominance

Questions 11 of 50

Question:Frequency of an allele in a isolated population may change due to:

Answers Choices:

gene flow

mutation

genetic drift

natural selection

Questions 12 of 50

Question:Mobile genetic elements in maize were discovered by:

Answers Choices:

H.G. Khorana

N.E. Borlaug

B. McClintock

D. Baltimore

Questions 13 of 50

Question:The term 'transposon' was introduced by:

Answers Choices:

Nirenburg and Khorana

Beadle and Tatum

Hedges and Jacob

Morgan and Bridges

Questions 14 of 50

Question:Maize with 10 pairs of chromosomes has linkage groups:

Answers Choices:

5

10

20

40

Questions 15 of 50

Question:Two linked genes a and b show 20% recombination. The individuals of a dihybrid cross between ++/++ X ab/ab shall show gametes:

Answers Choices:

++30 : ab30 : +a20 : +b20

++40 : ab40 : +a10 : +bl0

++50 : ab50

++80 : ab20

Questions 16 of 50

Question:An individual with cd genes was crossed with wild type ++. On the test crossing F1 the progeny was +c 105, +d 115, cd 880 and ++ 900. The distance between cd genes is:

Answers Choices:

11 map units

5.5 map units

44 map units

88 map units

Questions 17 of 50

Question:During meiosis crossing over occurs at:

Answers Choices:

Diakinesis

Leptotene

Pachytene

Zygotene

Questions 18 of 50

Question:Crossing over involves:

Answers Choices:

Exchange of genetic material

Addition of chromosomes

Duplication of chromosomes

Deletion of chromosomes

Questions 19 of 50

Question:Crossing over is advantageous because it brings about:

Answers Choices:

Linkage

Variation

Inbreeding

Stability

Questions 20 of 50

Question:Mutation is a change that is:

Answers Choices:

inherited

never inherited

responsible for plant growth

inherited only in F2 generation

Questions 21 of 50

Question:The major source of variations are:

Answers Choices:

Polyploidy

Segregation

Mutations

Chromosome aberrations

Questions 22 of 50

Question:Recessive mutations are expressed in:

Answers Choices:

next generation

same generation

heterozygous condition

homozygous condition

Questions 23 of 50

Question:Haploid number is 10. What shall be the tetra-somic number?

Answers Choices:

19

40

20

22

Questions 24 of 50

Question:Haploid chromosome number is 12. What is the number in a monosomic?

Answers Choices:

22

23

25

26

Questions 25 of 50

Question:Monosomies are:

Answers Choices:

2n + 1

n

2n - 1

2n - 2

Questions 26 of 50

Question:A polyploid with genomes derived from same original species is:

Answers Choices:

Amphidiploid

Allopolyploid

Autopolyploid

Autoallopolyploid

Questions 27 of 50

Question:A polyploid derived from F! hybrid between two species is:

Answers Choices:

Amphidiploid

Hexaploid

Autodiploid

Autopolyploid

Questions 28 of 50

Question:What is correct?

Answers Choices:

Raphanobrassica is autopolyploid

Tetraploid plants may have wider and extensive distribution

Multivalent formation occurs in allopoly­ploids

Aneuploidy occurs due to chromosome doubling

Questions 29 of 50

Question:Nitrous acid causes mutation by:

Answers Choices:

addition of a base pair

acting as a base analogue

hydrolysing base sugar linkage

removing amino group from bases

Questions 30 of 50

Question:Induction of mutation by X-rays was discovered by:

Answers Choices:

Luria

Morgan

Muller

Hugo de Vries

Questions 31 of 50

Question:Identify the one which causes mutation:

Answers Choices:

Cosmic rays

Crossing over

Gamma rays

Colchicine

Questions 32 of 50

Question:Name the mutagen:

Answers Choices:

\(HN{O_2}\)

\(S{O_2}\)

\(N{H_3}\)

\(CO\)

Questions 33 of 50

Question:When a mutation is limited to the substitution of one nucleotide pair for another, it is called a

Answers Choices:

sugar phosphate deletion

point mutation

translocation

base inverse

Questions 34 of 50

Question:Not all base pair substitution in DNA alter the activity of the product enzyme's activity. Those that do must alter the enzyem's

Answers Choices:

total size

secondary structure

tertiary structure

ratio of sulphur to nitrogen

Questions 35 of 50

Question:Which is not an example of cytoplasmic inheritance?

Answers Choices:

Female sterility in maize

Kappa particle inheritance

Sigma substance inheritance

Plastid inheritance

Questions 36 of 50

Question:Kappa particles are:

Answers Choices:

submicroscopic granules formed by the folding of the naked DNA

endosymbionts representing the gram-neg­ative bacteria species

viral particles capable of self-perpetuation in the host cytoplasm

protozoan parasites whose multiplication is controlled by the host metabolites

Questions 37 of 50

Question:An auxotroph is:

Answers Choices:

a plant that responds by bending towards the sun

an organism that depends on another organism for meeting its nutritional requirements

a mutant which has lost its ability to synthe­size one or more essential compounds

a plant that is able to synthesize its own carbohydrates

Questions 38 of 50

Question:There are 40 chromosomes in the somatic cells of the house mouse. How many chromosomes does a mouse receive from its father?

Answers Choices:

38

19

20

1

Questions 39 of 50

Question:Which of the following was used in experiments by Beadle and Taturn to propose one gene-one enzyme hypothesis?

Answers Choices:

Nostoc

Drosophila

E.coli

Neurospora

Questions 40 of 50

Question:The most important character for which T.H. Morgan selected Drosophila for his experiments:

Answers Choices:

easily available

large chromosomes

short life cycle

convenience in breeding

Questions 41 of 50

Question:Attachment of a chromosomal fragment resulting in addition of one or more genes to a chromosome is called:

Answers Choices:

Duplication

Translocation

Inversion

Deletion

Questions 42 of 50

Question:Each chromosome carries a distinct region which plays a fundamental role in chromosome movement during mitosis. This region is:

Answers Choices:

chromatid

centriole

telomere

centromere or kinetochore

Questions 43 of 50

Question:The largest number of chromosomes are found in:

Answers Choices:

Lemna

Adiantum

Ophioglossum

Neurospora

Questions 44 of 50

Question:In cytoplasmic inheritance, characters are transmitted:

Answers Choices:

maternally

paternally

morphologically

by bacterial multiplication

Questions 45 of 50

Question:Which one of the following is wrong?

Answers Choices:

Bivalents are formed in zygotene.

Chiasmata are formed in diplotene

Crossing over takes place between two sister chromatids.

Crossing over takes place in diplotene

Questions 46 of 50

Question:Minor changes at gene level are described as:

Answers Choices:

Reverse mutations

Forward mutations

Point mutations 

Chromosomal mutations

Questions 47 of 50

Question:Molecular weight of chromosome of yeast cell is:

Answers Choices:

\(0.5 \times {10^9}\)

\(1 \times {10^9}\)

\(2.25 \times {10^9}\)

\(8.5 \times {10^9}\)

Questions 48 of 50

Question:Genes located on mitochondrial DNA:

Answers Choices:

shows biparental inheritance

are not inherited like nuclear genes

generally shows maternal inheritance

always inherited from the male parent

Questions 49 of 50

Question:The reason why some mutations which are harmful do not get eliminated from gene pool is that:

Answers Choices:

they have future survival value

they are dominant and show up more frequently

genetic drift occurs because of a small population

they are recesive and carried by heterozygous individuals

Questions 50 of 50

Question:A chromosome carrying the centromere at one of the ends is called

Answers Choices:

acentric

acrocentric

telocentric

metacentric