MODEL EXAM NO-1

 

1. Global agreement in specific control strategies to reduce the release of ozone depleting  substances, was adopted by:

1) The Montreal Protocol

2) The Koyoto Protocol

3) The Vienna Convention

4) Rio de Janeiro Conference

2. What is true about Bt toxin ?

1) Bt protein exists as active toxin in the Bacillus.

2) The activated toxin enters the ovaries of the pest to sterilise it and thus prevent its  multiplication.

3) The concerned Bacillus has antitoxins.

4) The inactive protoxin gets converted into active form in the insect gut.

3. T.O. Diener discovered a:

1) Free infectious DNA

2) Infectious protein

3) Bacteriophage

4) Free infectious RNA

4. One of the synthetic auxin is:

1) IAA

2) GA

3) IBA

4) NAA

5. A person likely to develop tetanus is immunised by administering:

1) Preformed antibodies

2) Wide spectrum antibiotics

3) Weakened germs

4) Dead germs

6. The genetic defect - adenosine deaminase (ADA) deficiency may be cured permanently by:

1) administering adenosine deaminase activators.

2) introducing bone marrow cells producing ADA into cells at early embryonic stages.

3) enzyme replacement therapy.

4) periodic infusion of genetically engineered lymphocytes having functional ADA cDNA.

7. Which of the following plant species you would select for the production of bioethanol ?

1) Zea mays

2) Pongamia

3) Jatropha

4) Brassica

8. What is not true for genetic code?

1) It is nearly universal

2) It is degenerate

3) It is unambiguous

4) A codon in mRNA is read in a non-contiguous fashion

9. Removal of introns and joining the exons in a defined order in a transcription unit is called:

1) Tailing

2) Transformation

3) Capping

4) Splicing

10. Semiconservative replication of DNA was first demonstrated in:

1) Escherichia coli

2) Streptococcus pneumoniae

3) Salmonella typhimurium

4) Drosophila melanogaster

11. Steps taken by the Government of India to control air pollution include:

1) compulsory PUC (Pollution Under Control) certification of petrol driven vehicles which

tests for carbon monoxide and hydrocarbons.

2) permission to use only pure diesel with a maximum of 500 ppm sulphur as fuel for

vehicles.

3) use of non-polluting Compressed Natural Gas (CNG) only as fuel by all buses and

trucks.

4) compulsory mixing of 20% ethyl alcohol with petrol and 20% biodiesel with diesel.

12. Which of the following is not used as a biopesticide ?

1) Trichoderma harzianum

2) Nuclear Polyhedrosis Virus (NPV)

3) Xanthomonas campestris

4) Bacillus thuringiensis

13. Montreal Protocol aims at:

1) Biodiversity conservation

2) Control of water pollution

3) Control of CO2 emission

4) Reduction of ozone depleting substances

14. DDT residues are rapidly passed through food chain causing biomagnification because DDT is:

1) moderately toxic

2) non-toxic to aquatic animals

3) water soluble

4) lipo soluble

15. Select the incorrect statement from the following:

1) Galactosemia is an inborn error of metabolism

2) Small population size results in random genetic drift in a population

3) Baldness is a sex-limited trait

4) Linkage is an exception to the principle of independent assortment in heredity

16. Use of anti-histamines and steroids give a quick relief from:

1) Nausea

2) Cough

3) Headache

4) Allergy

17. Chipko movement was launched for the protection of:

1) Forests

2) Livestock

3) Wet lands

4) Grasslands

18. Whose experiments cracked the DNA and discovered unequivocally that a genetic code is a "triplet"?

1) Hershey and Chase

2) Morgan and Sturtevant

3) Beadle and Tatum

4) Nirenberg and Mathaei

19. Which of the following shows coiled RNA strand and capsomeres?

(1) Polio virus

(2) Tobacco mosaic virus

(3) Measles virus

(4) Retrovirus

20. Which one of the following is wrongly matched?

(1) Transcription- Writing information from DNA to- RNA

(2) Transcription- Using information in m- RNA to make protein

(3) Repressor protein - Binds to a operator to stop enzyme synthesis

(4) Operon- Structural genes, operator and promoter.

21. Transformation was discovered by:

(1) Meseson and stahl

(2) Hershey and chase

(3) Griffith

(4) Waston and crick

22. An analysis of chromosomal DNA using the Southern hybrization technique does not use:

(1) Electrophoresis

(2) Blotting (3) Autoradiography

(4) PCR

23. Which vector can clone only a small fragment of DNA?

(1) Bactrial artifical chromosome

(2) Yeast artificial chromosome

(3) Plasmid

(4) Comid

24. Choose the correctly matched pair:

(1) Inner lining of salivary ducts- Ciliated epithelium

(2) Moist surface of buccal cavity- Glandular epithelium

(3) Tubular parts of nephrons- Cuboidal epithelium

(4) Inner surface of bronchioles- Squamous epithelium

25. In'S' phase of the cell cycle:

(1) amount of DNA doubles in each cell.

(2) amount of DNA remains same in each cell.

(3) chromosome number is increased

(4) amount of DNA is reduced to half in each cell.

26. Approximately seventy percent of carbon-dioxide absorbed by the blood will be transported to the lungs:

(1) as bicarbonate ions

(2) in the form of dissolved gas molecules

(3) by binding to R.B.C.

(4) as carbamino-haemoglobin

27. Person with blood group AB is considered as universal recipient because he has:

(1) both A and B antigens on RBC but no antibodies in the plasma.

(2) both A and B antibodies in the plasma.

(3) no antigen on RBC and no antibody in the plasma

(4) both A and B antigens in the plasma but no antibodies

28. Which of the following causes an increase in sodium reabsorption in distal convoluted tubule?

(1) Increase in aldosterone levels

(2) Decrease in antidiuretic hormone levels

(3) Decrease in aldosterone levels

(4) Decrease in antidiuretic hormone levels

29. A man whose father was colour blind marries a woman who had a colour blind mother and normal father. What percentage of male children of this couple will be colour blind ?

(1) 25%

(2) 0%

(3) 50%

(4) 75%

30. In a population of 1000 individuals 360 belong to genotype AA, 480 to Aa and the remaining 160 to aa, Based on this data, the frequency of allele A in the population is :

(1) 0.4

(2) 0.5

(3) 0.6

(4) 0.7

31. A human female with Turner's syndrome:

(1) has 45 chromosomes with XO

(2) has one additional X chromosome.

(3) exhibits male characters

(4) is able to produce children with normal husband.

32. Commonly used vectors for human genome sequencing are:

(1) T- DNA

(2) BAC and YAC

(3) Expression Vectors

(4) T/A Cloning Vectors

33. Read the following four statements (A-D) :

(A) In transcription, adenosine pairs ·with uracil

(B) Regulation of lac operon by repressor is referred to as positive regulation

(C) The human genome has approximately 50,000 genes

(D) Haemophilia is a sex-linked recessive disease

34. How many of the above statements are right ?

(1) Three

(2) Four

(3) One

(4) Two

35. A test cross is carried out to :

(1) Predict whether two traits are linked

(2) Assess the number of alleles of a gene

(3) Determine ·whether two species or varieties ·will breed successfully

(4) Determine the genotype of a plant at Fz

36. In genetic engineering, the antibiotics are used :

(l) To select healthy vectors

(2) As sequences from where replication starts

(3) To keep the cultures free of infection

( 4) As selectable markers

37. The idea of mutations was brought forth by :

(1) Gregor Mendel, who worked on Pisum sativum

(2) Hardy Weinberg, who worked on allele frequencies in a population

(3) Charles Darwin, ·who observed a wide variety of organisms during sea voyage

(4) Hugo do Vries, who worked on evening primrose

38. Which one of the following cellular parts is correctly described ?

(1) Centrioles- sites for active RNA synthesis

(2) Ribosomes- those on chloroplasts are larger (80s) ·while those in the cytoplasm are smaller (70s)

(3) Lysosomes - optimally active at a pH of about 8.5

(4) Thylakoids- flattened membranous sacs fanning the grana of chloroplasts

39. A fall in glomerular filtration rate (GFR) activates -

(1) Adrenal cortex to release aldosterone

(2) Adrenal medulla to release adrenaline

(3) Posterior pituitary to release vasopressin

( 4) Juxta glomerular cells to release rennin

40. Which one of the fo ll owing represents a palindromic sequence in DNA?

( I) 5'-CCAATG- 3'

3'-GAA TCC- 5'

(2) 5'-CA TT AG-3'

3'-GAT AAC-5'

(3) 5'-GATACC-3'

3'-CCT AAG-5'

(4) 5'-GAATTC-3'

3'-CTT AAG-5'

41. What is it that forms the basis of DNA Fingerprinting ?

(1) The relative difference in the DNA occurrence in blood, skin and saliva

(2) The relative amount of DNA in the ridges and grooves of the fingerprints

(3) Satellite DNA occurring as highly repeated short DNA segments

( 4) The relative proportions of purines and pyrimidines in DNA

42. The chitinous exoskeleton of arthropods is formed by the polymerisation of:

(1) D- glucosamine

(2) N- acetyl glucosamine

(3) lipoglycans

(4) keratin sulphate and chondroitin sulphate

43.Which of the following immunoglobulins does constitute the largest percentage in human milk?

(1) Ig M

(2) Ig A

(3) Ig G

(4) Ig D

44. Doctors use stethoscope to hear the sounds produced during each cardiac cycle. The second sound is heard when:

(1) Ventricular walls vibrate due to gushing in of blood from atria

(2) Semilunar valves close down after the blood flows into vesels from ventricles

(3) AV node receives signal from SA node

(4) AV valves open up

45. The cutting of DNA at specific locations became possible with the discovery of:

(1) Probes

(2) Selectable markers

(3) Ligases

(4) Restriction enzymes

46. The DNA molecule to which the gene of interest is integrated for cloning is called:

(1) Vector

(2) Template

(3) Carrier

(4) Transformer

47. A pleiotropic gene:

(1) is a gene evolved during Pliocene.

(2) controls a trait only in combination with another gene

(3) controls multiple traits in an individual.

(4) is expressed only in primitive plants

48. Golden rice is a genetically modified crop plant where the incorporated gene is meant for biosynthesis of :

(1) Vitamin C

(2) Omega 3

(3) Vitamin A

(4) Vitamin B

49. A gene showing codominance has:

(1) alleles tightly linked on the same chromosome

(2) alleles that are recessive to each other

(3) both alleles independently expressed in the heterozygote

(4) one allele dominant on the other

50. A colour blind man marries a woman with normal sight who has no history of colour blindness in her family. What is the probability of their grandson being colour blind ?

(1) 1

(2) Nil

(3) 0.25

(4) 0.5