Practice Test


Q1) Transfer RNA is synthesized: Show Answer


Q2) DNA is believed to be the genetic material because: Show Answer


Q3) In a DNA molecule, the sugars: Show Answer


Q4) If replication were conservative, which of the following banding patterns would Meselson and Stahl have found in the fourth generation? (Note: concentration refers to concentration of DNA). Show Answer


Q5) Which of the following would not be used in preparing recombinant DNA? Show Answer


Q6) Non-sense codons are present in: Show Answer


Q7) If a cell is treated with nucleic acid destructing material, which will firstly be prevented? Show Answer


Q8) DNA synthesis takes place in: Show Answer


Q9) For deciphering the genetic code, H. G. Khorana synthesized: Show Answer


Q10) The experimental system used in the studies on the discovery of replication of DNA has been: Show Answer


Q11) RNA- synthesis may be restricted by: Show Answer


Q12) X-Ray diffraction technique was used by Wilkins and Franklin to ascertain structure of: Show Answer


Q13) The functional genetic unit is: Show Answer


Q14) The base sequence for a nucleic acid segment is given as GAG, AGG, GGA, CCA. From this it can be concluded that it is a segment of a: Show Answer


Q15) A DNA strand is directly involved in the synthesis of all the following except: Show Answer


Q16) Which one of the following is specific for a amino acid? Show Answer


Q17) Which is required for protein synthesis? Show Answer


Q18) DNA polymerase is required for the synthesis of: Show Answer


Q19) Amino acid is carried by RNA at its: Show Answer


Q20) In yeast alanyl-tRNA, the number of nucleotides are: Show Answer


Q21) At 3' end t-RNA involved in transfer of amino acids: Show Answer


Q22) Replication of DNA in eukaryotes commences from: Show Answer


Q23) Streptomycin and related antibiotics bind to small sub-units of ribosomes in prokaryotes and they: Show Answer


Q24) Sickle cell anaemia is caused by change in: Show Answer


Q25) Heredity is brought about by transference from one generation to another of a substance with definite chemical having specific molecular constitution was mentioned by: Show Answer


Q26) Okazaki segments are: Show Answer


Q27) Transcription is the process by which: Show Answer


Q28) The one aspect which is not a salient feature of genetic code, is its being: Show Answer


Q29) Transcription is carried out by: Show Answer


Q30) mRNA of eukaryotes is synthesized with the help of: Show Answer


Q31) Which of the following is called adapter molecule? Show Answer


Q32) DNA replication is aided by: Show Answer


Q33) The element required for the activation of DNA and DNA polymerase is: Show Answer


Q34) For studying the metabolism of DNA radioautographic technique is used involving: Show Answer


Q35) The recent technique used for separating fragments of DNA is: Show Answer


Q36) Technique for detecting and screening the nutritional mutant in Neurospora crassa was developed by: Show Answer


Q37) A DNA molecule in which both strands have radioactive thymine is allowed to duplicate in an environment containing non-radioactive thymine. What will be the correct number of DNA molecules that contain same radio-active thymine after three duplications? Show Answer


Q38) What is the name of Noble laureates in relation with DNA? Show Answer


Q39) The first amino acid in any polypeptide chain in prokaryotes is always: Show Answer


Q40) A polypeptide is produced as dictated by mRNA, the number of bases on the mRNA that code for the polypeptide portion containing N-terminal amino acid and next 13 amino acid is: Show Answer


Q41) The transformation experiment conducted by Avery, MacLeod and McCarthy using Diplococcus bacteria proved that: Show Answer


Q42) "Degenerate" codes are when: Show Answer


Q43) The degeneracy in genetic code was found by: Show Answer


Q44) Normally GUG specifies valine amino acid, but when AUG is initiation codon then it specifies which one of the following amino acid? Show Answer


Q45) The site of protein synthesis is: Show Answer


Q46) The semi-conservative mode of DNA replication was proved by: Show Answer


Q47) A sequence of three bases which stands for an amino acid is called: Show Answer


Q48) Various metabolic activities of the cell are controlled and directed by: Show Answer


Q49) The RNA transporting amino acid to the protein synthesizing site is called: Show Answer


Q50) Select the specific base pairs of DNA: Show Answer


Q51) mRNA in prokaryotes is: Show Answer


Q52) The bits of DNA formed join with each other by an enzyme: Show Answer


Q53) Catalytic property of RNA was discovered by: Show Answer


Q54) Which is correct sequence according to increasing molecular weight? Show Answer


Q55) The two strands of DNA are: Show Answer


Q56) The diameter of DNA molecule is: Show Answer


Q57) The hydrogen bonds between adenine and guanine are: Show Answer


Q58) The approximate life span of m-RNA is: Show Answer


Q59) Which one of the following bases is found only in the RNA and not in DNA? Show Answer


Q60) RNA controls the synthesis of: Show Answer


Q61) A protion of DNA has ACT, CAT, TCA, what would be the sequence of complementary DNA? Show Answer


Q62) The term heterochromatin was given by: Show Answer


Q63) Histones occupy the major grooves of DNA at an angle of: Show Answer


Q64) There are special protein that help to open up DNA double helix in front of replication fork. These proteins are: Show Answer


Q65) If the DNA codons ATG ATG ATG and a cytosine base is inserted at the beginning, which of the following will result? Show Answer


Q66) If the sequence of bases in DNA is ATTCGATG, then the sequence of bases in its transcript will be: Show Answer


Q67) H. G. Khorana got the Noble Prize on: Show Answer


Q68) The transfer of genetic material from one cell to another by a phage is called: Show Answer


Q69) Autocatalytic function is shown by: Show Answer


Q70) In which of the following places, messenger RNA is found in a living cell? Show Answer


Q71) The function of a non-sense codon is: Show Answer


Q72) Functional unit of DNA which specifies the formation of a single peptide is: Show Answer


Q73) A mutant DNA is caused by insertion of extra base to DNA by a mutagen: Show Answer


Q74) The single stranded strand of nucleotide between a gene and a polypeptide is: Show Answer


Q75) r-RNA is transcribed on DNA template by: Show Answer


Q76) The number of polymerase in eukaryotic and prokaryotic cells are: Show Answer


Q77) Which of the following is not correct for DNA chain? Show Answer


Q78) Two strands of DNA are coiled around: Show Answer


Q79) DNA duplication occurs in: Show Answer


Q80) Which is not required for polypeptide synthesis? Show Answer


Q81) Which is the correct sequence of code transfer involved in the formation of a polypeptide? Show Answer


Q82) The flow of information from DNA to mRNA is called: Show Answer


Q83) Nucleic acids are polymers of: Show Answer


Q84) Two strands of DNA are attached by hydrogen bonds between: Show Answer


Q85) Satellite DNA is present in: Show Answer


Q86) Plasmids are: Show Answer


Q87) The genetic code is called degenerate code because: Show Answer


Q88) Anticodon is present on: Show Answer


Q89) The first translated codon in any mRNA is always: Show Answer


Q90) The instructions for the synthesis of a protein coat in a cell are always inscribed in the form of a: Show Answer


Q91) m-RNA is produced in the: Show Answer


Q92) The synthesis of polypeptide chain begins at the: Show Answer


Q93) Cracking the genetic code in vitro was largely the work of: Show Answer


Q94) The double helix makes a complete turn: Show Answer


Q95) Which one of the following pair is correctly matched? Show Answer


Q96) Lac-operon is related to: Show Answer


Q97) Which site of tRNA molecule hydrogen binds to a mRNA molecule? Show Answer


Q98) Which one of the following pair is correctly matched? Show Answer


Q99) A gene which synthesizes a repressor protein is: Show Answer


Q100) In an operon, the RNA polymerase binds to: Show Answer


Q101) Which of the following is a recombinant DNA? Show Answer


Q102) Which of the following is empolyed in recombinant DNA technology? Show Answer


Q103) Which one of the following units is unrelated to DNA or gene? Show Answer


Q104) Genetic engineering would not have been possible if one of these were absent: Show Answer


Q105) Which of the following organelles is associated with genetic engineering? Show Answer


Q106) In genetic engineering, the cutting DNA segment, which of the enzymes is used? Show Answer


Q107) A gene may best be defined according to its: Show Answer


Q108) In DNA sugar and phosphate form backbone of the molecule. The adjacent sugars are joined to each other by: Show Answer


Q109) Khorana synthesized a biologically functional tyrosine suppressor t-RNA of E. coli in 1979 it contained: Show Answer


Q110) The enzyme needed for repairing DNA break and releasing tension caused by rotation of DNA molecule is: Show Answer


Q111) When pure DNA was digested by nuclease, DNA fragments of all sizes were obtained. But when chromatin was digested with same enzyme, DNA fragmets of sizes, multiples of a smallest unit size were obtained. This suggests that in the chromatin, histone proteins are associated with DNA all along its length: Show Answer


Q112) An antibiotic which inhibits translation in eukaryotes is: Show Answer


Q113) Gene controls: Show Answer


Q114) Okazaki fragments are seen on: Show Answer


Q115) RNA primer is formed over: Show Answer


Q116) In general bacterial genes are regulated at the time of: Show Answer


Q117) The activity of repressor depends upon whether: Show Answer


Q118) Who followed the trail of Griffith's work and proved DNA is the genetic material? Show Answer


Q119) Which object did Hershey and Chase (1952) choose to confirm that DNA is the hereditary material? Show Answer


Q120) Who was not awarded Nobel Prize alongwith Watson, Crick and Wilkins for an extensive work on the structure of DNA? Show Answer


Q121) The function of helix-destabilizing proteins is to: Show Answer


Q122) Genes are located in a linear-fashion on the: Show Answer


Q123) The genetic code was cracked by: Show Answer


Q124) Why a protein cannot be a genetic material? Show Answer


Q125) The helical model for DNA given by Watson and Crick was: Show Answer


Q126) In function of 'DNA polymerase' is to help in the conversion: Show Answer


Q127) During protein synthesis, amino acids recognize and get attached to t-RNA with help of: Show Answer


Q128) Genes in the intervening non-functional DNA segments are called: Show Answer


Q129) Which of the following is correct? Show Answer


Q130) Genes are made up of: Show Answer


Q131) Hargobind Khorana is credited for the synthesis of: Show Answer


Q132) To mobile DNA elements which move into the genome through RNA copies are called: Show Answer


Q133) During a cell cycle, the DNA undergoes replication: Show Answer


Q134) Each codon present on m-RNA and anticodon present on t-RNA is composed of: Show Answer


Q135) Defective copies of functional genes are called: Show Answer


Q136) The structural stability of the double helix of DNA is ascribed largely to: Show Answer


Q137) Which of the RNA is smallest and used in feeding of amino acid to a ribosome? Show Answer


Q138) After reaching the cytoplasm the mRNA attaches itself to: Show Answer


Q139) Formation of new DNA strand during replication occurs in: Show Answer


Q140) Which of the following can break and reseal DNA strand during replication? Show Answer


Q141) Replication of DNA is: Show Answer


Q142) When in a DNA, A-T becomes T-A and G-C becomes C-G, the pehnomenon is called: Show Answer


Q143) DNA segments (genes) have been found to move out of choroplasts and go into mitochondria. These have been termed as: Show Answer


Q144) DNA replication is: Show Answer


Q145) In 'Z' DNA pitch of each turn of helix is: Show Answer


Q146) The biochemical nature of gene (DNA) was shown by: Show Answer


Q147) 'Z' DNA shows: Show Answer


Q148) Approach of Meselson and Stahl to establish the semi-conservative replication of DNA was to use: Show Answer


Q149) Which of the following enzymes is required for DNA to RNA formation? Show Answer


Q150) Addition of sugar residue to proteins termed glycosylation occurs in: Show Answer


Q151) Enzymes involved in an unwinding of DNA at replication are: Show Answer


Q152) Aminoacyl synthetase enzyme takes part in: Show Answer


Q153) tRNA attaches amino acid at its: Show Answer


Q154) During protein synthesis peptide bond is established between: Show Answer


Q155) Which one of the following chemical characterisitics is not common to all living beings? Show Answer


Q156) Because the amino acids are represented by more than one codon, the genetic code is said to be: Show Answer


Q157) The messenger RNA is termed as a working copy of the exact information contained in a segment of DNA strand. The process is called: Show Answer


Q158) The genes which continuously change their position on a chormosome are called: Show Answer


Q159) Certain genes do not generate functional m-RNA for any protein. Such genes are termed: Show Answer


Q160) RNA directed DNA polymerase is: Show Answer


Q161) Names-Nirenberg, Ochoa, Gamow, Khorana, Crick bring to your mind: Show Answer


Q162) When mRNA is synthesised on DNA the unwanted DNA regions are removed and regions coding for amino acids are joined together. This process is referred to as: Show Answer


Q163) Pyrimidine dimers in DNA are formed when the cells are exposed to: Show Answer


Q164) DNA elements which can switch their position are called: Show Answer


Q165) Initiation of polypeptide chain in protein synthesis is induced by: Show Answer


Q166) Who among the following established that RNA is the genetic material? Show Answer


Q167) On Laggin strand, new DNA is synthesized in short segments, called: Show Answer


Q168) Resistance to antibiotics is a genetic process that spreads naturally from one type of bacterium to: Show Answer


Q169) In vitro synthesis of polyribonucleotides and RNA was made by: Show Answer


Q170) The scientist who first synthesised DNA in vitro was: Show Answer


Q171) Artificial synthesis of DNA was done by: Show Answer


Q172) The best method to improve genetic quality of mankind is: Show Answer


Q173) Reference transcription in eukaryotes : What is the correct relation? Show Answer


Q174) If a chromosomes is fractured at two points by X-rays, the resulting segments may show fusion at the site of breakage: Show Answer


Q175) Which of the following antibiotics prevent polypeptide chain elongation in eukaryotes but not in bacteria? Show Answer


Q176) As per template theory, amino acid first combines with: Show Answer


Q177) RNA synthesis is continued by RNA-polymerase and: Show Answer


Q178) Genes which are active all the time synthesising substance needed by the cell are called? Show Answer


Q179) Which statement is wrong about DNA? Show Answer


Q180) If the bases sequence of one strand of DNA is GAT, TAG, CAT, GAC, what shall the sequence on its complementary strand? Show Answer


Q181) Ligase enzyme is used for: Show Answer


Q182) During protein synthesis amino acids recognise and get attached to tRNA with the help of: Show Answer


Q183) Genetic code consists of: Show Answer


Q184) Okazaki fragments are seen during: Show Answer


Q185) The Tryptophan operon is an example of: Show Answer


Q186) When two genetic loci produce identical phenotypes in cis as well as as trans position, they are considered to be: Show Answer


Q187) Restriction Endonuclease is used for cutting: Show Answer


Q188) Nuclease enzyme cause fragmentation of DNA at sites not protected by proteins. When pure DNA was digested with a nuclease, DNA fragments of all sizes were obtained but when chromatin was similarly digested DNA fragments of sizes that were obtained. This suggested that in the chromatin the histone proteins are associated with DNA all along its length: Show Answer


Q189) Because most of the amino acids are represented by more than one codon the genetic code is said to be: Show Answer


Q190) During elongation of polypeptide chain, sigma factor is: Show Answer


Q191) During the replication of DNA the two daughter molecules are obtained in the following manner: Show Answer


Q192) DNA contains the bases: Show Answer


Q193) For structure of nucleic acid, which of the following statements is wrong: Show Answer


Q194) In recent years, considerable attention is being given to DNA protein interactions, because expression of genes is regulated through binding of specific proteins on regulatory DNA sequences. The pattern of protein binding of DNA can be studied by: Show Answer


Q195) There are several proteins that help to open up DNA double helix in front of the replication fork. These belong to the category of: Show Answer


Q196) Amino acids are transferred from cytoplasm to site of protein synthesis by: Show Answer


Q197) ATP is not spent during: Show Answer


Q198) Nature of DNA replication is: Show Answer


Q199) The maximum concentration of RNA is found in: Show Answer


Q200) An anticodon is a complementary to the nucleotide triplet in: Show Answer


Q201) In bacterial chromosomes, the nucleic acid polymers are: Show Answer


Q202) The nitrogenous organic base purine occuring in RNA is: Show Answer


Q203) In cell cycle, DNA replication takes place in: Show Answer


Q204) Protein synthesis in an animal cell takes place: Show Answer


Q205) Which step of translation does not consume a high energy phosphate bond? Show Answer


Q206) DNA synthesis can be specifically measured by estimating the incorpotation of radio labelled: Show Answer


Q207) Three codons causing chain termination are: Show Answer


Q208) The RNA that picks up specific amino acids from the amino acid pool in the cytoplasm to ribosome during protein synthesis is called: Show Answer


Q209) In eukaryotes, after transcription of mRNA, some of its nucleotides are removed before it is translated into polypeptide. The nucleotides which are removed from mRNA are called: Show Answer


Q210) If a completely radioactive double stranded DNA molecule undergoes two rounds of replication in a non-radioactive medium, what will be radioactive status of the four resulting molecules? Show Answer


Q211) The chemical knives of DNA are: Show Answer


Q212) Radioactive thymidine when added to the medium surrounding living mammalian cells gets incorporated into the newly synthesized DNA. Which of the following types of chromatin is expected to become radioactive if cells are exposed to radioactive thymidine as soon as they enter the S phase? Show Answer


Q213) Human immuno deficiency virus (HIV) has a protein coat and a genetic material which is: Show Answer


Q214) Proteins are synthesised by the process: Show Answer


Q215) Correct sequence of code transfer during polypeptide formation is: Show Answer


Q216) Which is true of DNA helicases? Show Answer


Q217) Mechanism of DNA duplication is mainly: Show Answer


Q218) During cell cycle, the DNA replication occurs in: Show Answer


Q219) One bacterium which has extensively used in genetic engineering work in plants is: Show Answer


Q220) One of the similarities between DNA and RNA is that both: Show Answer


Q221) Protein synthesis occurs: Show Answer


Q222) E. coli about to replicate was placed in a medium containing radioactive thymidine for five minutes. Then it was made to replicate in a normal medium. Which of following observation shall be correct? Show Answer


Q223) Which of the following cut the DNA from specific places. Show Answer


Q224) m-RNA is synthesised on DNA in template in which direction: Show Answer


Q225) Types of RNA polymerase required in nucleus for RNA synthesis in eukaryotes: Show Answer


Q226) Gene and cistron words are sometimes used synonymously because: Show Answer


Q227) HIV has a protein coat and a genetic material which is: Show Answer


Q228) Largest bacterial plasmid has Kilobases: Show Answer


Q229) Cauliflower mosaic virus has: Show Answer


Q230) DNA polymerase that helps in DNA replication is of: Show Answer


Q231) Degeneration of a genetic code is attributed to the: Show Answer


Q232) Down's syndrome is caused by an extra copy of chromosome number 21. What percentage of offspring produced by an affected mother and a normal father would be affected by this disorder? Show Answer


Q233) During translation initiation in prokaryotes, a GTP molecule is needed in: Show Answer


Q234) During transcription, the DNA site at which RNA polymerase binds is called: Show Answer


Q235) The total number of nitrogenous bases in human genome is estimated to be about: Show Answer


Q236) Which of the following pairs is correctly matched with regard to the codon and the amino acid coded by it? Show Answer


Q237) DNA repairing is done by: Show Answer


Q238) The function of promoter of lac-operon is to: Show Answer


Q239) When a mutation is limited to the substitution of one nucleotide for another, it is called: Show Answer


Q240) During transcription, if nucleotide sequence of DNA strand, that is being coded is ATACG, then the nucleotide sequence in m-RNA would be: Show Answer


Q241) During replication of a bacterial chromosome, DNA synthesis starts from the replication origin site and: Show Answer


Q242) In the genetic code dictionary, how many codons are used to code for all the 20 essential amino acids? Show Answer


Q243) Which one of the following triplet codes is correctly matched with its sepecificity for an amino acid in protein synthesis or as 'start' of 'stop' signal? Show Answer


Q244) Find the correct match: Show Answer


Q245) The codon for anticodon 3'UUA5' is: Show Answer


Q246) Splicing of RNA depends on: Show Answer


Q247) In lac operon system, lac gene-I codes for: Show Answer


Q248) Which of the following is important for transcription? Show Answer


Q249) Production of a human protein in bacteria by genetic engineering is possible because: Show Answer


Q250) E.coli vells with a mutated Z gene of the lac operon cannot grow in medium containing only lactose as the source of energy because: Show Answer


Q251) Which one of the following makes use of RNA as a template to synthesize DNA? Show Answer


Q252) In the synthesis of which of the following, the DNA molecule is not directly involved? Show Answer


Q253) Which one of the following hydrolyses internal phosphodiester bonds in a polynucleotide chain? Show Answer


Q254) Transcription requires which of these enzyme? Show Answer


Q255) Genes that are continuously functional and whose regulations are at tissue level as in kidney, liver are known as: Show Answer


Q256) DNA duplication takes place during: Show Answer


Q257) One gene-one enzyme hypothesis was posulated by: Show Answer


Q258) Which antibiotic inhibits interaction between tRNA and mRNA during bacterial protein synthesis? Show Answer


Q259) Amino acid sequence, in protein synthesis is decided by the sequence of: Show Answer


Q260) During protein synthesis in an organism at one point the process comes to a halt. Select the group of the three codons from the following, from which any one of the three could bring about this halt. Show Answer


Q261) The Okazaki fragments in DNA chain growth: Show Answer


Q262) The length of DNA molecule greatly exceeds the dimensions of the nucleus in eukaryotic cells. How is this DNA accommondated? Show Answer


Q263) A sequential expression of a set of human genes occurs when a steriod molecule binds to the: Show Answer


Q264) During transcription, RNA polymerase holoenzyme binds to a gene promotor and assumes a saddle-like structure. What is it's DNA-binding sequence? Show Answer


Q265) One gene-one enzyme relationship was established for the first time in: Show Answer


Q266) Telomere repetitive DNA sequences control the function of eukaryote chromosomes because they: Show Answer


Q267) Molecular basis of organ differentiation depends on the modulation in transcription by: Show Answer


Q268) The two polynucleotide chains in DNA are: Show Answer


Q269) Choose the wrong statement: Show Answer


Q270) In the DNA molecule: Show Answer


Q271) Which one of the following pairs of codons is correctly matched with their function or the single for the particular amino acid: Show Answer


Q272) Polysomes formed by: Show Answer


Q273) Which one of the following also acts as a catalyst in a bacterial cell? Show Answer


Q274) Which of the nucleotide composition will be possible if DNA is double stranded? Show Answer


Q275) Which of the following is incorrect? Show Answer


Q276) In case of F. Griffith experiment on Streptococcus pneumoniae, which of the following is not able to cause pneumonia: Show Answer


Q277) Which of the following photographed x-ray diffraction pictures of crystalline DNA? Show Answer


Q278) The right handed DNA can acquire a left handed structure at least over a short distance. It will: Show Answer


Q279) Three types of DNA can be differentiated on the basis of their: Show Answer


Q280) The DNA replication in most bacteria starts at a single point, origin and moves: Show Answer


Q281) What is the composition of larger subunit of prokaryotic ribosome? Show Answer


Q282) Tetracycline inhibits protein synthesis in bacteria by inhibiting: Show Answer


Q283) Overlapping genes: Show Answer


Q284) Which statement is incorrect? Show Answer


Q285) Virus genome replicates in: Show Answer


Q286) For replication viruses use: Show Answer


Q287) The activity of nuclease does not affect phage DNA because it has: Show Answer


Q288) Match the list I and II and select the answering using the code given below the list:
1. Friedrick Griffith : Phenomenon of transformation
2. Gamow : A sequence of 3 nucleotide codes for a single amino acid
3. F. Miescher : Isolated DNA for the first time Show Answer


Q289) Match the list I and II and select the correct answer using the code given below in the list:
1. Ligase : Joins short segments of DNA together
2. DNA polymerase : Cuts DNA at specific DNA sequence
3. Helicase : Breaks the hydrogen bonds between complementary pairs during DNA replication
Show Answer


Q290) In a hypothetical mRNA, the codon would normally be translated as follows:
UUG : Leu,
UUG : Leu,
UUU : Val,
UGU : Cys,
UAU : Tyr
If single G-residue is inserted between the second and 3rd bases: Show Answer