Practice Test


1) The pattern of inheritance of white eye colour in Drosophila that the gene is:


2) A haemophilic man marries a normal homozygous woman. What is the probability that their son will be haemophilic?


3) A haemophilic man marries a normal homozygous woman. What is the probability that their daughter will be haemophilic ?


4) A man known to be victim of haemophilia marries a normal woman whose father known to be a bleeder, then it may be expected that:


5) Sex-linked inheritance can be known from:


6) Evidence that crossing over occurs at four strand stage comes from:


7) Twenty two pairs of similar human chromosomes are called:


8) Relative morphologies of chromosomes of an individual indicate his/her:


9) Segregation of hereditary factor occur during the process of:


10) Crossing over may result into:


11) During meiosis the exchange of chromosomal segments between maternal and paternal chromatids is known as:


12) The points where the crossing over takes place between chromatids of two homologous chromosomes of a pair are:


13) If the two genes for two different traits are located on the same chromosome, and inherited together they are termed as:


14) Who proposed the 'Fibre folded Model' of chromosome structure?


15) After examining the blood groups of a couple, the doctor has advised them not to have more than one child. The blood group of the couple are likely to be:


16) Usually the recessive character is expressed only when present in double recessive condition. However, single recessive gene can express itself in human beings when the gene present on:


17) Marriage between blood relations or cousins should not be performed, because:


18) More the distance between the two genes on a chromosome:


19) A linkage group is explained as:


20) Plotting of specific location of genes on the chromosome is known as:


21) Complete linkage is observed in:


22) Most acceptable theory for crossing over is:


23) The percentage of crossing over will be more if:


24) In Drosophila, a fly whose one half of the body is male and the other half female, referred to as:


25) Crossing over takes place between:


26) X and Y chromosomes determine sex was discovered by:


27) Which of the following is not heritable?


28) The process of mating of individuals closely related than the average of population of which they belong is called:


29) A pair of contrasting characters located on the homologous chromosome, are termed as:


30) Drosophila has four pairs of chromosomes. How many linkage groups does it have?


31) Linkage in Drosophila was first discovered by:


32) Sex chromosomes may be defined as:


33) A species of Neurospora which can grow on a single minimal medium is known as:


34) A single Drosophila chromosome possesses a gene for red eyes and a gene for straight wings. These genes may be separated as a result of:


35) As a result of linkage and crossing over:


36) When, a green plant was self fertilized, the progeny had 209 green seedlings and 14 white seedlings. The above results indicated that:


37) The genes which tend to be inherited together are said to be:


38) If a child's father is colourblind and the mother has one gene for colourblindness, the probaility that the child may be colour blind will be:


39) Low temperature is mutagenic in:


40) Sum total of all the genetic information in the breeding members of a population at a time is known as:


41) Lethal genes are those which:


42) The traits controlled by gene located on X chromosome are said to be:


43) Which of the following is wholly a genetic trait in man?


44) A gene located on Y chromosome and therefore transmitted from father to son is known as:


45) Multiple alleles are:


46) In Mirabilis normal leaves
(A) and variegated leaves (B) occur in different plants. If (B) male is crossed with (A), female normal leaves occur in the hybrid. But if (A) male is crossed with (B) female, variegated leaves occur. It is an instance of:


47) In a large number of crosses of two heterozygous round and yellow seeded pea plants, the fractions of offspring that would probably appear wrinkled and green is:


48) Of the following, gene maps can best be constructed on the basis of the study of:


49) Reassortment occurs as a consequence of random orientation of pairs of homologous chromosome at:


50) Which one of the following statement is incorrect? Linkage:


51) Maize has 10 pairs of chromosomes. Linkage groups present in it are:


52) Number of strands in each chromosome pair during crossing over is:


53) Gene order:


54) If there is a large percentage of crossing over between genes A and B, the explanation is that the genes are located / converted:


55) The rare appearance of a white eyed female or a red eyed male in a cross between a white eyed female Drosophila and a red eyed male, may best be attributed to which one of the following?


56) The frequency of mutation:


57) A pleiotropic mutation:


58) The mutation in germ cells:


59) Neurospora is more suitable for genetic studies because:


60) Mutation brings about:


61) Most of the mutations are:


62) Mutagens are:


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


64) The person who used X-rays to cause mutation was:


65) Mutation do not result in:


66) Mutations which are not dominant are not lost by a gene pool. It is known as:


67) Which are necessary conditions for the Hardy Weinberg principle for applying to genetic population?


68) Which of the following support the idea that mutational changes have been more frequent at the time when living cells were first evolved:


69) The process of deletion and transfer of several genes is:


70) The term mutation has been given by:


71) Nutritional mutants were first isolated by:


72) The mutations which prove fatal for the organism are called:


73) Genetic variability in sexually reproducing plants is caused by:


74) Perceptible change in the phenotype of an organism is brought about by:


75) Genetic mutation occurs in:


76) A wild organism (bacterium) that will grow on a minimal medium is known as:


77) A mutant organism (bacterium) that will not grow on a minimal medium but does so on addition of some growth factors is known as:


78) Gibberish mutation is caused by:


79) Hereditary variation in plants have been obtained through the use of:


80) A normal girl whose father was albino marries a man who is albino what ratio of normal and albino can be expected among their offspring?


81) The rate of mutation can be increased by:


82) In nature the rate of mutation is:


83) The smallest element or sub-division of a gene which can be affected by a mutation is:


84) Organic evolution due to large discontinuous variation was proposed by:


85) Segment of DNA having ACC, GAC, AGC, CGC, ACA and AAA lost first base due to deletion. The effect is:


86) New varieties of crop plants are produced through:


87) How are new characteristics produced in plants?


88) Mutations are caused by:


89) Point mutations affect DNA's:


90) To be of evolutionary importance, mutation must occur at the level of:


91) The gene which increases the frequency of mutation in other genes is referred to as:


92) Haemolytic jaundice is caused due to a dominant gene but only 10 per cent of the people actually develop the disease. A heterozygous man marries a homozygous normal woman. What proportion of the children would be expected to develop the haemolytic disease?


93) Chemical mutagens are far more hazardous to man than radiation because:


94) There is no masking of expression of genes in Neurospora because:


95) The research in human genetics established in 1901 has been slow because:


96) Inborn errors of metabolism in human beings were first studied by:


97) Who coined the term Eugenics?


98) The basic approaches to human genetics are:


99) If brown eye character is dominant over blue eye, the parent being blue eyed, what is the percentage chance of getting brown eyed child:


100) The packing (compaction) ratio of a metaphasic chromosome is:


101) A doctor's son:


102) The creation of mutation is called:


103) Arrangement of chromosomes in the order of decreasing length is termed:


104) Second baby will be born dead if:


105) Syndrome due to extra 18th autosomal chromosome is known as:


106) D-group chromosomes are:


107) When hybrid is superior to its parents, it is termed:


108) Number of sex linked disorders discovered so far in human being are:


109) The human chromosomes are divided into 7 groups, B-group chromosomes are:


110) Male human having breast like females, sterility, degenerating seminiferous tubules, mental retardation are known as:


111) When linked characters or genes are inherited together through two or more generations, it is called as:


112) Ancestral history of an individual indicate his / her:


113) In mongolism a patient possesses:


114) The number of Barr-bodies in Turner's syndrome is:


115) When number of Y spots is 2 in Klinefelter's syndrome sex chromosome complement is:


116) Individual with more than two sets of chromosomes show many:


117) Presence of extra finger or toe known as:


118) Turner's syndrome is characterised by:


119) The human beings having XXY or XXXY chromosomes develop:


120) Individuals with Klinefelter's syndrome are characterised by:


121) The characteristic symptoms resulting from various chromosomal abnormalities are called:


122) The chormosomal abnormality due to the presence of one abnormal 21 st chromosome (Total 47) in man is called:


123) Female with how many Barr bodies is normal:


124) The chromosomal abnormality due to the presence of one additional 13th chromosome in man is:


125) Which disorder is not hereditary?


126) Protoplast fusion or parasexual hybridization was first done between man and mouse cells by:


127) Whenever expression of a trait is limited to one sex, it is known as:


128) Red green colour blindness is known as:


129) Genic balance theory was proposed by:


130) Males are XO and females XX in case of:


131) If the female is carrier and male normal, what percentage of female offspring will be haemophilic:


132) Sickle cell anaemia is due to:


133) A male child would be born to parents if:


134) A man heterozygous for sickle cell anaemia will show in his blood:


135) The inheritance of sickle cell anaemia disease, the gene which cause this disease has a lethal effect when present in:


136) The ratio between carrier, disease free and diseased individual on marriage between two carriers of sickle cell anaemia will be:


137) What would be the ratio between colour blind and normal individuals in 2nd generation-progeny of colour blind man and normal woman?


138) Philadelphia chromosome is reported in patients suffering from:


139) The ratio between colour blind and normal sons colour blind and normal daughters in 2nd generation on marriage between a colour blind female and a normal male will be:


140) Children of colour blind mother and a normal father would be:


141) Which of the following blood groups is a universal recipient?


142) Which of the following blood groups is a universal donor?


143) Rh-negative individuals are:


144) If one of the parents is of 'A' blood group and the other O, their progeny possibly represents:


145) A person with blood group Rh - ve type A, may safely donate blood to a person whose blood is:


146) If the mother has Rh - ve blood and the developing embryo has Rh - ve blood, the mother's blood would most likely:


147) Identical twins come from:


148) I. Q. (Intelligence quotient) is calculated by dividing:


149) Polyploidy was discovered by:


150) A dominant sex linked gene is known to cause baldness in men but no effect in women. What proportation of male offspring from heterozygous parents will be bald?


151) Parasexual hybridisation means fusion between:


152) The fusion between related species is referred to as:


153) Haemophilia is caused due to lack of:


154) Raphanobrassica is cross between:


155) Knowing that Albinism is determined by a recessive gene in the children born to a normal couple prove that:


156) In human being the sex of the child is differentiated and can be determined with 95% confidence by studying:


157) Phenylketonuria is a genetic disease which refers to:


158) The presence of tail in human child at birth is an example of:


159) The genotype of Drosophila individual having sexual characters of female is:


160) A family has five girls and no son. Probability of son in the 6th child will be:


161) Human female has 44 + XX chromosomes in somatic cells. How many chromosomes will be present in secondary oocyte:


162) Frequency of Down's syndrome is increased with:


163) The unit of distance between genes on the chromosome is:


164) The probability of a cross over between two gene loci is proportional to:


165) With respect to the type of haemoglobin produced, the gene for sickle cell trait in human beings is:


166) Which prevent union of chromosomes?


167) Which of the following chromosomes are typically banded?


168) Datura is classial example of:


169) Concept of Mapping was first suggested by:


170) When sex is determined before fertilization:


171) An abnormal human male phenotype involving an extra X chromosome (XXY) is a case of:


172) Each chromosome at the anaphase stage of a bone marrow cell in our body has:


173) Barr body in mammals present:


174) The polytene chromosomes were discovered for the first time in:


175) The point at which the polytene chromosomes appear to be attached together is known as:


176) The complete haploid set of chromosomes in each nucleus of a given species is referred to as the:


177) Genes for antibiotic resistance are located on:


178) The chromosome puffs on salivary gland chromosomes are:


179) If the haploid number of chromosomes in a cell is 12, the monosomic number will be:


180) Bacterial chromosome has:


181) Which of the following blood groups are dominant?


182) A nucleosome contains the following group of histone proteins:


183) The term heterochromatin was coined by:


184) A mother with blood group B has a child with blood group O, what will be the genotype of the father:


185) Which of the following XY combination is associated with features of Klinefelter syndrome:


186) How many linkage groups are present in man?


187) Plastid has been acting as hereditary particles in cytoplasmic inheritance, was told by:


188) Haemophilia is due to:


189) Muton is called:


190) Solenoid model explains the:


191) Number of base pairs in a nucleosome is about:


192) Genes are absent on:


193) Drosophila has how many pairs of chromosomes?


194) Chromosomes replicate at:


195) Counting of chromosomes can be done at:


196) Males of which animals have chromosomes less than in females:


197) Males are haploid whereas females are diploid in:


198) Chromosomes were first observed by:


199) The term chromosomes was given by:


200) Sudden heritable changes occur naturally in organisms was stated by:


201) Who porposed the theory of mutation?


202) Haemophilia is due to:


203) Haemophilia is:


204) Movement of gene to a non-homologous chromosome is called as:


205) Normally mutations are:


206) Mutations which alter the phenotypes slightly are:


207) Gene is:


208) Genome is called:


209) Chimera is produced due to:


210) Allopolyploids have:


211) Phenylketonuria is:


212) Haemophilia A is due to deficiency of clotting factor:


213) Chromosomes X was first observed by:


214) Protanopia is:


215) Deuteranopia is:


216) Sex limited genes are present in:


217) The idiogram of C group of human chromosomes are:


218) Plasmids in bacteria include:


219) Trisomy (2n + 1) in Datura (Jimson weed) was first studied by a geneticist who also coined the term polyploidy:


220) An organism or cell having a chromosome number exactly multiple of haploid number is known as:


221) Haemophilia is more common in males because it is a:


222) Bar eye in Drosophila is due to:


223) Normally all genes occur in pairs but some genes occupying position on the X chromosome having no alleles on Y chromosome. This indicates that:


224) Maize has 10 pairs i.e. 20 chromosomes. How many linkage group should it possess?


225) Mental retardation in man associated with sex chromosomal abnormality is usually due to:


226) Father of human genetics / biochemical genetics is:


227) The term crossing over was coined by:


228) In haploids the monohybrid ratio is:


229) The somatic chromosome complement in all human beings is:


230) For making important contribution in respect to the nature of genes, the Nobel prize was awarded to:


231) Who induced mutations by X-ray irradiation in fruit fly for the first time?


232) An exchange of segments between the two non-homologous chromosomes is called:


233) If a part of the chromosome gets detached and lost during the cell division, the mutation so produced is called:


234) Aneuploidy is the term applied for:


235) Haemophilia / Bleeder's disease was discovered by:


236) The genetic information needed for the complete development of an individual is contained in a haploid set of chromosomes. Which type of reproduction gives evidence for above statement?


237) Telocentric chromosome differs from submetacentric chromosome in that:


238) A man homozygous for brown colour marries a lady heterozygous for brown colour. If the gene for brown colour is dominant, what will be the fate of their children:


239) Human gene determining sex at seventh week of pregnancy called TDF is present on:


240) Which of the following disease is related to haemopilia?


241) A woman with two genes, one for haemophilia and a gene for colour blindness on one of the 'X' chromosomes marries a normal man. Progeny will be:


242) In Down's Syndrome, karyotyping has shown that the disorder is associated with trisomy of chromosome number 21 usually due to:


243) Mental retardation in man associated with sex chromosomal abnormality is usually due to:


244) The reason why vegetatively reproducing crop plants are best suited for maintaining hybrid vigour is that:


245) Albinism is known to be due to an atuosomal recessive mutation. The first child of a couple with normal skin pigmentation was an albino. What is the probaility that their second child will also be an albino?


246) The hereditary material present in the bacterium Escherichia coli is:


247) After crossing two plants, the progenies are found to be male sterile. This phenomenon is found to be maternally inherited and is due to some genes which reside in:


248) A fruit fly is heterozygous for sex-linked genes. When mated with a normal female fruit fly, the male-specified chromosome will enter egg cells in the proportion of:


249) Genetic identity of a human male is determined by:


250) A mutation at one base of the first codon, of a gene produces a non-functional protein. Such a mutation is called:


251) Genes are packed into a bacterial chromosome by:


252) Different muations referrable to the same locus of chromosomes give rise to:


253) Genes located on mitochondrial DNA:


254) A person with the sex chromosome XXY suffers from:


255) Sex chromosomes remain in:


256) Polyploidy can result from:


257) The barr body is observed by:


258) In a linear chromosome, map distance between few loci are as follows: a - b= 10, b - c = 4, a - d = 3, a - c = 6 The cross over frequency between c and d is:


259) Two dominant, non-allelic genes are exactly 50 map units apart. What is means is that linkage:


260) Cytoplasmic male sterility is inherited:


261) Barr body in human female is formed by:


262) Lampbrush chromosomes occur during:


263) H. J. Muller was awarded Nobel Prize for his:


264) In which of the following diseases, man has an extra X-chromosome:


265) A man with a certain disease marries a normal woman. They have eight children (3 daughters and 5 sons). All the daughters suffer from their father's disease but none of the sons are affected. Which of the following mode of inheritance do you suggest for his disease:


266) Crossing over takes place during which of the following stage:


267) Mongoloid syndrome is due to:


268) The exchange of genetic material between chromatids of paired homologous chromosomes during first meiotic division is called:


269) Sex factor in bacteria:


270) A person with 47 chromosomes due to an additional Y chromosome suffers from a condition called:


271) Sex-linked disease is:


272) Sometimes chromosome number increase or decrease due to:


273) In Hybrid break down:


274) Haemophilic disease of new born baby is caused by:


275) Recessive characters are expressed when present:


276) In order to determine whether variations of a character in a population were genetically controlled, the most appropriate producer will be:


277) The most striking example of point mutation is found in a disease called:


278) Which is the main category of mutation?


279) Cross over frequency is proportional to:


280) Polytene chromosomes were first studied in:


281) In multifactorial inheritance:


282) Complete linkage in Drosophila males:


283) Sickle cell anaemia: (i) follows the same inheritance pattern as that of haemophilia. (ii) follows the same inheritance pattern as that of albinism. (iii) is a sex linked trait. (iv) is due to a single recessive point mutation leading to the substitution of a single amino acid in the b-charn of haemoglobin of the sentences written as:


284) The human disease which is inherited as a simple recessive trait:


285) If frequency of allele B in a population is 0.70 then the frequency of allele b would be:


286) A mother with B blood group has two children, one with A blood group and other with O blood group. Her husband has O blood group. The correct sentence regarding the above data is:


287) Carrier of a genetic disorder:


288) Drosophila flies with XXY genotype are females but in case of humans, such individuals are abnormal males (Klinetelter's syndrome). This indicates that:


289) Mongoloid idiocy in humans is also known as:


290) One function of the telomeres in a chromosome is to:


291) During organ differentiation in Drosophila an organ is often modified to another organ such as wings could be replaced by legs. Genes responsible for such metamorphosis are called:


292) Extranuclear chromosomes occurs in:


293) Extranuclear inheritance occurs in:


294) No. of Bar body in XXXX female is:


295) Male XX and female XY sometimes occur due to:


296) A and B genes are linked. What shall be genotype of progeny in a cross between. AB/ab and ab/ab?


297) Probability of four sons to a couple is:


298) What is true for plasmid?


299) Genes for cytoplasmic male sterility in plants are generally located in:


300) The mutation which is not transferred to the offspring:


301) When an animal has both sexes (male or female), it is called:


302) Germplasm theory was proposed by:


303) The example of XY linked gene inheritance is:


304) A person having 45 chromosomes and Y-chromosome absent, is suffering from


305) Haemophilia is a:


306) Which of the following variations are temporary and have nothing to do with the last or next generation?


307) In Drosophila, the sex is determined by:


308) Christmas disease is another name for:


309) Pattern baldness, moustahes and beard in human males are exmples of:


310) A double stranded DNA having 100, 000 bp will have a length of:


311) Map distance of genes is calculated by:


312) Sex determination in Drosophila melanogaster is based on:


313) When a diploid female plant is crossed with a tetraploid male plant, then ploidy of endosperm cells in the resulting seed is:


314) In a mutational event, when adenine is replaced by guanine, it is a case of:


315) After the mutation at a genetic locus, the character of an organism changes due to change in:


316) Which of the following value is generally constant for a given species?


317) One of the parents of a cross has a mutation in its mitochondria segregation of F_2 progenies, mutation is found in:


318) Lack of independent assortment of genes A and B in fruit fly Drosophila is due to:


319) Total number of base pairs found in human genome is:


320) Polytene chromosomes in salivary glands of Drosophila are formed as a result of:


321) When chromosome breaks and the two fragments join together after rotating by 180^@ is called:


322) Mitochondrial inheritance occurs:


323) In Limnaea shell coiling is due to:


324) Transposons are:


325) A nucleosome is a portion of the chromonema containing:


326) The diagrammatic representation of the chromosomes of an individual is called:


327) What are episomes?


328) The genes are located on chromosomes. It was proposed by:


329) Histones are present in:


330) Sudden and heritable change in a character of an organism is called:


331) Which of the following is incorrectly paired?


332) When the chromosome number of a given organism has one additional chromosome in one of the following pairs, the condition is known as:


333) Aneuploidy is:


334) The major chemical components of chromosomes are DNA, RNA, histones and non-histone proteins. Besides, there is one very important inorganic chemical, which is:


335) The salivary gland chromosomes in the dipteran larvae, are useful in gene mapping because:


336) A woman with normal vision, but whose father was colour blind, marries a colour blind man. Suppose that the fourth child of this couple was a boy. This boy:


337) A woman with 47 chromosomes due to three copies of chromosome 21 is characterized by:


338) Haemophilia is more commonly seen in human males than in human females because:


339) A man and a woman, who do not show any apparent signs of a certain inherited disease, have seven children (2 daughters and 5 sons). Three of the sons suffer from the given disease but none of the daughters are affected. Which of the following mode of inheritance do you suggest for this disease?


340) Genes for cytoplasmic male sterility is generally located in:


341) G-6-P dehydrogenase deficiency is associated with haemolysis of:


342) The "Cri-du-chat" syndrome is caused by change in chromosome structure involving


343) The correct pathway for the synthesis of skin pigment is:


344) Which one of the following techniques is employed in human genetic counselling?


345) Edward's, Patau's , Down's syndromes are due to:


346) Barr body is found in the nucleus during:


347) Both sickle cell anemia and Huntington's chorea are:


348) In which mode of inheritance do you expect more material influence among the offspring?


349) Cri-du-chat syndrome in humans is caused by the:


350) Genes present in the cytoplasm of eukaryotic cells are found in


351) What would be the number of chromosomes in the cells the aleurone layer in a plant species with 8 chromosomes in its synergids?


352) If a colourblind woman marries a normal visioned man, their sons will be:


353) Which one of the following is the most suitable medium for culture of Drosophila melanogaster:


354) Assertion (A): Phenylketonuria is a recessive hereditary disease caused by body's failure to oxidise an amino acid phenylalanine to tyrosine because of defective enzyme.
Reason (R): It results the presence of phenylalanine acid in urine.


355) Gynaecomastia is a symptom of:


356) The distance between the genes a, b, c and d in mapping units are a - d = 3.5; b - c = 1; a - b = 6; c - d = 1.5; a - c = 5. Find out the sequence of arrangement of these genes


357) Which one of the following conditions in humans is correctly matched with its chromosomal abnormality / linkage:


358) Which one of the following conditions correctly describes the manner of determining the sex in the given example?


359) A person with unknown blood group under ABO system, has suffered much blood loss in an accident and needs immediate blood transfusion. His one friend who has a valid certificate of his own blood type, offers for blood donation without delay. What would have been the type of blood group of the donor friend?


360) Mutation can be induced with:


361) What are those structures that appear as "beads on strings" in the chromosomes when viewed under electron microscope?


362) Sutton and Boveri proposed the chromosome theory of inheritance (1902) which was expanded by T. H. Morgan and others. In 1909 who replaced the term factor with gene as basic unit of inheritance?


363) In a Morgan's cross of Drosophila involving yellow body (y) and white eyed mutant (w) females and wild type males (grey body and red eyed). What is the % age of yellow bodied and red eyed flies and grey bodied and white eyed types?


364) The product of recombination is called:


365) Chiasma type hypothesis is based on:


366) Earlier the genetic maps of chromosomes were constructed based on recombination frequency. In recent years most detailed as precise genetic maps have been prepared by:


367) Calvin Bridge while experimenting on Drosophila demonstrated:


368) Cri-du-chat syndrome is caused due to:


369) If the centromere is included in inverted segment during inversion, it is called:


370) The organisms having multiple of monoploid number (X) are called:


371) Polyploids have important application in:


372) The length of 46 human chromosomes taken together is about 2 metres. What is the length of large circular chromosome of bacterium E.coli?


373) Nucleosome of eukaryotic chromosome consists of:


374) Cystic fibrosis caused due to:


375) Alzheimer disease involves loss of memory and ability of judgement. It is common among?


376) In a medico legal case of accidental interchange between two babies in a hospital, the baby of the blood group A could not be rightly given to couple with:


377) In which one of the following combinations (1-4) of the number of chromosomes is the present day hexaploid wheat correctly represented?


378) Which of the following is correct:


379) Parts of DNA which switch their positions are called


380) DNA replication requires


381) In 1868 DNA was discovered by the Swedish biochemist


382) In 1928 Frederick Griffith showed that the hereditary material can pass from one type to bacteria into another through a process called


383) The transforming substance of Pneumococcus in Griffiths experiment was


384) What was the finding of Hershey and Chase?


385) What is the distance between two base pairs in the double helix model of DNA?


386) Hydrogen bonds occur between which of the following constituents of DNA?


387) In one strand of DNA the sequence of bases is AAATGGCCCTT, then the complementary sequence of bases on the other side of the strands would be


388) The difference in A, B and Z forms of DNA lies in


389) In 1957, Meselson and Stahl concluded from their studies that


390) In bacterial chromosome


391) Replication is continuous in


392) Transcription refers to the


393) Generally only one strand of DNA is transcribed. This strand is called


394) Which of the following RNA polymerase catalyses the formation of transfer RNA in eukaryotes?


395) What is a codon?


396) The chain initiating codon is


397) The chain-terminating codon is


398) A larger cluster of ribosome is called


399) Nonsense codon is responsible for


400) Out of 64 codons how many of them code for amino acids?


401) Which one is not applicable in respect of genetic code?


402) Which one is correct?


403) One gene one enzyme hypothesis was proposed by


404) Which of the following is not associated with preparation of checker-board for genetic code?


405) Ligase is an enzyme required for


406) DNA duplication or multiplication is called


407) Escherichia coli with completely radioactive DNA was allowed to replicate in nonradioactive medium for two generations. Percentage of bacteria with radioactive DNA is


408) Initiation of polypeptide chain takes place through


409) Termination of polypeptide chain is brought about by


410) The process of translation relates to


411) Information transfer from RNA to DNA is called


412) Circular DNA is found in


413) Okazaki fragments are formed during


414) Nucleotide base present in DNA and not in RNA is


415) Pyrimidine base present in RNA in place of thymine of DNA is


416) Which of the following sugars is found in RNA?


417) RNA that picks up specific amino acid from amino acid pool of cytoplasm to carry it to ribosome during protein synthesis is


418) DNA duplex shows


419) Experimental evidence supporting concept of triplet genetic code was first provided by


420) If in a DNA molecule cytosine is 18%, the percentage of adenine would be


421) Genetic code translates the language of


422) Isotopes used in proving semiconservative replication of DNA were


423) Which is true according to Chargaffs rule?


424) How many pairs of nucleotides are present in one turn of DNA helix?


425) Reverse transcription was discovered by


426) The flow of information from DNA and mRNA and then to proteins is called


427) Watson and Crick proposed the model of DNA structure in


428) Nucleic acids are polymers of


429) Which is required for protein synthesis?


430) Synthesis of DNA from RNA temple occurs in


431) The site of tRNA that binds to mRNA is


432) Triplet codon refers to sequence of three bases on


433) Enzyme required for transcription is


434) DNA is present in


435) The functional unit of gene that specifies synthesis of one polypeptide is


436) Regulator gene controls chemical synthesis (operon system) by


437) The term cistron, recon and muton were proposed by


438) Bacterial nucleoid has


439) In operon model, RNA polymerase binds to


440) Which one of the following synthesizes a repressor protein?


441) Operon model of gene regulation in prokaryotes was proposed by


442) The smallest gene affected by mutation is


443) In Escherichia coli, lac operon is induced by


444) Lac operon is


445) Wild type Escherichia coli growing on medium having glucose is transferred to lactose containing medium. Which one of the following change will occur?


446) Viruses possess


447) In split genes, the coding sequences are called


448) Go through the following statements.
I. In DNA replication, the primer is small ribonucleotide polymer.
II. DNA acts as a template for synthesis of both DNA and RNA.
III. tRNA attaches amino acid at its 3' end.
IV. Blender experiment to prove DNA as genetic material was performed by Watson ad Crick.


449) If the sequence of bases in the coding strand of a double stranded DNA is 5' - GTTCGAGAGTC - 3', the sequence of bases in its transcript will be


450) Operator gene of lac-operon is turned on when lactose molecules bind to


451) Introns are part of DNA which


452) In operon model, regulator gene functions as


453) A gene that takes part in synthesis of polypeptide is


454) The part of operon producing repressor is called


455) Tryptophan operon of Escherichia coli is


456) DNA fingerprinting involves identifying differences in some specific regions in DNA sequence called as


457) The technique of DNA fingerprinting was initially developed by


458) Human Genome Project (HGP) was closely associated with the rapid development of a new area in biology called as


459) Who has established the fact that DNA is a helix of uniform diameter?


460) The process of transcription is terminated by


461) For transcription RNA polymerase attaches to the


462) Which of the following is true, if in a DNA adenine is represented by a, guanine by b, cytosine by c and thymine by d?


463) In a DNA molecule adenine will be equal to


464) Imagine an error occurring during DNA replication in a cell, so that where there is supposed to be a T in one of the genes there is instead a G. What effect will this probably have on the cell?


465) A particular __________ carries the information for making a particular polypeptide, but _________ can be used to make any polypeptide.


466) A sequence of pictures of polypeptide synthesis shows a ribosome holding two transfer RNAs. One tRNA has a polypeptide chain attached to it; the other tRNA has a single amino acid attached to it. What does the next picture show?


467) At one point as a cell carried out its day-to-day activities, the nucleotides GAT were paired with the nucleotides CUA. This pairing occurred


468) Human Genome Project was officially started in


469) Which of the following is true?
A. 'Operon hypothesis' was proposed by Jacob and Monod.
B. 'One gene-one enzyme theory' was proposed by Beadle and Tatum.
C. 'Southern blotting' is used in DNA fingerprinting.
D. Uracil bases remain present in DNA.


470) Adenosine is


471) Intron is -
A. Coding sequence.
B. Non-coding sequence.
C. Character of Prokaryotic genome.
D. Character of eukaryotic genome.


472) A transcription unit in DNA consists of -
A. A promoter.
B. The structural gene.
C. A terminator.
D. None.


473) In chromosome, DNA is associated with -
A. Negatively charged proteins.
B. Positively charged proteins.
C. Neutral proteins.
D. NHC protein.


474) Heterochromatin -
A. Is more densely packed.
B. It stains dark.
C. Is transcriptionally active.
D. Is transcriptionally inactive.


475) DNA -
A. acts as genetic material in all cellular organisms.
B. Was discovered by F. Meischer who named it as 'Nuclein'.
C. Is acidic in nature.
D. Cannot be digested by DNase.


476) In 1953 J. Watson and F. Crick proposed Double helix model of DNA and got Nobel Prize. Their model of DNA was based on -
A. X-ray diffraction of DNA produced by M. Wilkins and R. Franklin.
B. Griffith's experiment.
C. Hershey - Chase experiment.
D. Chargaff's rule of base equivalence (A + G / T + C = 1).


477) Euchromatin is -
A. Loosely packed.
B. Stains light.
C. Transcriptionally active.
D. Early replicating.


478) The phosphodiester bonds between nucleotides are called


479) In one polynucleotide chain of a DNA molecule the ratio of A + T / G + C is 0.3. What is the A + G / T + C ratio of the entire DNA molecule


480) Which one / ones did not affect the transformation?
A. DNAase
B. RNAase
C. Peptidase
D. Lipase


481) It is nonsense of think that DNA has


482) In DNA you find which type(s) of bond.
A. Phosphodiester
B. Phosphoester
C. Hydrogen
D. Glycosidic bond


483) The structures in chromatin seen as 'beads-on string' when viewed under electron microscope are called


484) A nucleosome consists of -
A. RNA
B. Protein
C. Histone octamer
D. 200 bps long DNA


485) A. Both DNA and RNA are able to mutate.
B. RNA being unstable, mutates at a faster rate.
C. RNA is also known to be catalytic, hence reactive.
D. The presence of thymine at place of uracil confers additional stability to DNA.


486) Protein synthesis involves -
A. Transcription
B. Translation
C. Transversion
D. Translocation


487) The structure of DNA is characterized by


488) Antiparallel relationship of the two strands of DNA refers to the


489) Which one/ones is/are false for DNA replication?


490) DNA polymerase -
A. Is the main enzyme for RNA synthesis.
B. Is DNA dependent DNA polymerising enzyme.
C. Is highly efficient enzyme.
D. It catalyses reaction with high degree of accuracy.


491) A sequence of three RNA base can function as -
A. Codon.
B. Gene.
C. Adticodon.
D. Nucleosides.


492) The difference(s) between mRNA and tRNA is/are that -
A. mRNA has more elaborated 3-dimensional structure due to extensive base-pairing.
B. tRNA has more elaborated 3-dimensional structure due to extensive pairing.
C. tRNA is usually smaller than mRNA.
D. mRNA bears anticodon but tRNA has codons.


493) Genetic code consists of -
A. Adenine and guanine.
B. Riboflavin and ATP.
C. Cytosine and Guanine.
D. Cytosine and Uracil.


494) Nucleic acids are made up of
A. Nitrogenous bases.
B. Amino acids.
C. Sugar.
D. Phosphate.


495) DNA replication needs


496) Transcription needs -
A. DNA template.
B. NTPs.
C. RNA polymerase.
D. Sigma and Rho factors.


497) The function of the promoter is to signal RNA polymerase as to -
A. Where to stop transcibing the DNA.
B. Where to start transcribing the DNA.
C. Which strand of the DNA to be read.
D. None.


498) In eukaryotes the gene expression is regulated at -
A. Transcriptional level.
B. Processing level.
C. Transport of mRNA from nucleus to the cytoplasm.
D. Translation level.


499) A translational unit in mRNA includes -
A. Start codon.
B. Stop codon.
C. Untranslated regions (UTR).
D. Coding sequence is located between the start codon and termination codon.


500) A. In eukaryotes there are at-least three RNA polymerase.
B. HnRNA has both exons and introns.
C. HnRNA is formed in both prokaryotes and eukaryotes.
D. Any mistake in DNA replication may cause mutation.


501) In prokaryotes, gene regulation occurs at the level of


502) In human -
A. Non-coding DNA is the most abundant.
B. The function of more than 50% discovered genes are unknown.
C. Less than 2% of genome codes for protein.
D. Total number of genes is 30,000.


503) Which of the following statements is/are incorrect about tRNA?
A. It binds to DNA, initiating translation.
B. It has a greater molecular weight than mRNA.
C. It transfers the code from the nucleus to cytoplasm.
D. There is at-least one form for each kind of amino-acid.


504) Transcription is most similar to


505) Satellite DNA -
A. Is classified in many catagories such as micro-statellites, minisatellites, etc. on the basis of base composition length of segments and number of repetitive units.
B. Normally does not code for any protein.
C. Shows polymorphism.
D. Forms the basis of DNA fingerprinting.


506) A. DNA polymorphism plays important role in evolution and speciation.
B. 99.9% nucleotides bases are exactly same in all people.
C. Chromosome 1 has the fewest genes (23) and Y-chromosome has most genes (2968).
D. BAC and YAC have been used in Human Genome Project.


507) Which one(s) is/are correct?
A. In prokaryotes singles type of RNA polymerase can transcribe mRNA, tRNA and rRNA.
B. In eukaryotes RNA polymerase I transcribes rRNA (28s, 18s and 5.8s) whereas RNA pol. III is responsible for transcription of tRNA, 5s rRNA and RNAs.
C. RNA pol. II trancribes HnRNA in eukaryotes.
D. Ribosomal large subunit has P and A-sites.


508) The human genome consists of over ___________ base pairs.


509) The current estimate of the number of genes in the human -


510) Which of the following is required in protein synthesis?
A. Ligase.
B. tRNA.
C. mRNA.
D. Endonuclease.


511) Polymorphism in DNA sequence -
A. Is the basis of genetic mapping of human genome.
B. Arises due to mutation.
C. Is the basis of DNA finger printing.
D. None.


512) Which of the following statements is correct about Human Genome Project


513) DNA has a alternate grooves


514) Similarity between DNA and RNA is that both have -
A. adenine.
B. Guanine.
C. Thymine.
D. Cytosine.


515) Genetic code is -
A. triplet.
B. Degenerate.
C. Nonambiguous.
D. Universal.


516) DNA replication involves -
A. Unwinding of helix.
B. Transcription.
C. Formation of primer strand.
D. Translation.


517) Which one is correct?
A. DNA cannot produce its copies without DNA polymerase.
B. DNA cannot produce RNA.
C. RNA can produce complementary DNA/cDNA.
D. DNA helps in protein synthesis.


518) Nucleosome contains -
A. RNA.
B. DNA.
C. Histones.
D. All of these.


519) AUG initiation codon occurs over


520) Split genes include -
A. Pseudoalleles.
B. Transposons.
C. Exons.
D. Introns.


521) The experimental proof for DNA as genetic material comes from -
A. Transformation.
B. Transduction.
C. Conjugation.
D. Mutation.


522) Which of the following statements about the work of Griffith, and then Avery, MacLeod and Mc Carty on Streptococcus pneumoniae is false?


523) Which of the following was not important evidence that helped advance the idea that DNA is the genetic material?


524) Which of the following statements about the Hershey-Chase experiment is false?


525) You estimate that cytosine represents 30% of the total pyrimidine content of DNA from a mouse cell. Using Chargaff's rules, you determine that the percentage of total nucleotides in the DNA represented by adenine is


526) Which of the following statements about the structure of DNA is false?


527) The unequivocal proof that DNA is the genetic material came from the experiment which utilized


528) How many adenylate residues are added at 3' end during the processing of hnRNA in eukaryotes?


529) Which of the following model organisms has been sequenced?


530) nu body of nucleosome consists of


531) Super solenoid model of nucleosome has


532) Which one of the following is used as marker chromosome?


533) The Human Genome Project as mega-project was a 13 year project coordinated by the


534) Sequencing of model organism like Caenorhabditis elegans (a free living non-pathogenic nematode) was achieved in April, 2003 with


535) Percentage of protein encoding genes and transposable elements in Human genome are respectively


536) SNP which is pronounced as 'snips' stands for


537) HGP methodology which includes identification of all the genes that express as RNA is referred as


538) According to Human Genome Project, the percentage of introns in human genome is approximately


539) The last human chromosome which sequence was completed in May 2006 is


540) Sequencing the whole set of genome that contains all the coding and non coding parts is


541) Father of DNA finger printing is


542) Find the incorrect match


543) Separation of DNA fragments into bands by electrophoresis is done on


544) Blotting technique involves transfer of DNA from


545) Enzyme utilized for the synthesis of RNA copolymers and homopolymers during deciphering of genetic code is


546) Choose the correct statement w.r.t. satellite DNA


547) The entire genetic code consist of _______ amino acids and ___________ codons.


548) The length of E. coli DNA and length of DNA in a human 2N cell is


549) The length of human DNA in a diploid cell is


550) Which of the following is the best order of sequential, increasing condensation (packing) of DNA


551) When chromatin is treated with nonspecific nucleases, what is the length of the resulting pieces of DNA?


552) In mammalian cells, the DNA of the centromere is characteristics of


553) What do telomeres do?


554) If gene code is tetraplet then what is the possible number of codons which code 20 types of amino acids


555) Of the _________ different possible codons, ________ specify amino acids and ______ signal stop.


556) Which of the following statements is true regarding introns?


557) Which mode of information transfer usually does not occur?


558) A geneticist isolate a gene for a specific trait under study. She also isolates the corresponding mRNA. Upon comparison, the mRNA is found to contain 1,000 fewer bases than the DNA sequence. Did the geneticist isolate the wrong DNA?


559) The effort to decipher the genetic code was led by _________ who was awarded Nobel Prize for is work


560) Transcription and translation of a gene composed of 30 nucleotides would form a protein containing no more than ________ amino acids.


561) During translation, the __________ site within the ribosome holds the growing amino acids chain while the ___________ site holds the next amino acid to be added to the chain.


562) Relative amounts (mole %) of nitrogen bases in a genomic DNA sample are as follows -
A : 24.7;
G : 24.1;
T : 32.7;
C : 18.5.
The most likely source of DNA is


563) An mRNA ready for translation would have


564) Dr. Venkataram Ramakrishnan is one of the three recipients of the 2009 Nobel Prize for Chemistry. He worked towards the elucidation of the three-dimensional structure of ribosomes. Ribosomes are involved in the biosynthesis of proteins and


565) Which one of the following also acts as a catalyst in a bacterial cell?


566) What are those structures that appear as 'beads-on-string' in the chromosomes when viewed under electron microscope?


567) During chromosome replication, the following events occur -
(i) Breaking of H bonds between bases.
(ii) Bonds between adjacent nucleotide form.
(iii) Winding brings about formation of two double helices.
(iv) Bases on free nucleotides bond with bases on DNA strands.
Which of the following shows the correct sequence?


568) The histone protein that attaches to DNA strands between nucleosomes is _________.


569) Chromosomes must condense to approximately 1/500the of their length for cell division. The first reduction is _______.


570) If a small chromosome consists of 500,000,000 nucleotides, how any nucleosomes will attach to that chromosome?


571) The unequivocal proof of DNA as the genetic material came from the studies on a


572) In m-RNA base sequence is 5' AAC CAA GAC CCC 3' what is the possible no. of codons in case of overlapping and non overlapping respectively


573) Which of the following is not the characteristic feature of genetic code


574) More than one initiation codon and termination codons are found in which RNA


575) Which one of the following is a wrong statement regarding mutations?


576) 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.
How many of the above statements are right?


577) What is it that forms the basis of DNA Fingerprinting?


578) Crick, one of the discoverer of DNA double helical structure, was the man of


579) The number of codons that code different amino acids is


580) Some amino acids are coded by more than one codon hence the code is


581) Out of 64 codons, the number of codons with GGG is


582) Which one of the following is not a part of a transcription unit in DNA?


583) Ribosomal RNA is actively synthesized in


584) If one strand of DNA has the nitrogenous base sequence at ATCTG, what would be the complementary RNA strand sequence


585) Removal of introns and joining of exons in a defined order during transcription is called


586) Removal of RNA polymerase III from nucleoplasm will affect the synthesis of


587) Which enzyme/s will be produced in a cell in which there is a nonsense mutation in the lac Y gene?


588) Which one of the following is not an application of DNA finger printing?


589) Cyanogen bromide is used in __________.


590) If the DNA codons are ATG ATG ATG and a cytosine base in inserted at the beginning, which of the following will result?


591) The blind approach of sequencing the whole set of genome is referred as


592) The commonly used 'DNA finger printing technique' in forensic science is simply a method called


593) DNA finger printing is based on


594) In DNA fingerprinting


595) DNA fingerprinting is done by a technique called


596) Restriction fragment length polymorphism (RFLP) is


597) In order to identify the person who committed a crime. Forensic experts will need to extract DNA from the tissue sample collected at the crime scene, and conduct one of the following procedures for DNA finger-printing analysis


598) PCR and Restriction Fragment Length Polymorphism are the methods for


599) Which of the DNA sources would be suitable for DNA finger printing -
A - hair,
B - semen,
C - saliva,
D - RBC


600) Which one of the following is wrongly matched?


601) Transformation was discovered by


602) Select the correct option


603) Commonly used vectors for human genome sequencing are


604) Which codon is not an indicator of completion of protein synthesis?


605) Which of the following events would occur in lac operon of E. coli when the growth medium has high concentration of lactose?


606) A stretch of DNA consisting of 10-20 bases is most appropriately called as


607) hnRNA is converted to mRNA by


608) Which of the following is correctly matched?


609) Of the total number of genes estimated in human genome, nearly 10% are contained in


610) A transcription unit in DNA is defined primarily by the -
(i) promoter
(ii) structural genes
(iii) okazaki fragments
(iv) adenylate residues
(v) terminator


611) Read the following statements and choose the correct option -
(i) RNA polymerase associates transiently with 'Rho' factor to initiate transcription.
(ii) In bacteria, transcription and translation takes place in the same compartment.
(iii) RNA polymerase I is responsible for transcription of tRNA.
(iv) When hnRNA undergoes capping process, adenylate residues are added at 3' end in a template independent manner.
(v) hnRNA is the precursor of mRNA.


612) Choose the correct statement


613) Aminoacylation of tRNA is essential for


614) In eukaryotic genes, coding sequences are called


615) Which site of the tRNA pairs through hydrogen bonding with the triplet codon on mRNA?


616) Which of the following is the main polymerising enzyme of DNA replication in bacteria?


617) During termination of translation


618) The nuclear structure observed by Henking in 50% of the insect sperm after spermatogenesis was


619) What is nucleosome?


620) Choose the correct statement among the following


621) Which was the first catalytic molecule during evolution of life?


622) The deflection of pitch angle between two successive steps (rungs) of DNA is


623) RNA polymerase-I transcribes eukaryotic ribosome which does not consist of


624) In a 3.2 kbp long piece of DNA, 820 adenine bases were found. What would be the number of cytosine bases?


625) In 125 amino acid sequence if the codon for 25th amino acid is mutated to UAA, then


626) Which of the following information is essential to determine the genetic map distance between two genes located on the same chromosome?


627) Lactose (Lac) Operon is regulated by


628) The enzyme peptidyl transferase of prokaryotes resides in


629) Select correct combination of statements for DNA fingerprinting.
(i) It is ELISA based technique.
(ii) It is PCR based technique.
(iii) It is used by forensic scientists.
(iv) It is based on the fingerprint of the individual.
(v) It is a test for paternity.


630) What makes the exact copying of DNA molecules possible?


631) Which molecule has its synthesis directly controlled by DNA?


632) In sea urchin DNA, which is double stranded, 17% of the bases were shown to be cytosine. The percentages of the other three bases expected to be present in this DNA are


633) Gene regulation governing lactose operon of E. coli that involves the lac I gene product is


634) Satellite DNA is important because it


635) Identify the correct order of organisation of genetic material from largest to smallest


636) Which one of the following is not applicable to RNA?


637) Balbiani rings are sites of


638) The repressor of the operon is synthesized


639) If the length of DNA is 1.36 mm, the number of base pairs and nucleosomes in it will be?


640) If an E. coli with heavy DNA is allowed to grow for 80 minutes in a culture medium of N14H4CI, then what would be the proportion of heavy, light and hybrid densities DNA molecule respectively?


641) A molecule acts as genetic material must fulfill how many of the following criteria?


642) Which of the following figures correctly represents the replication?


643) If a codon consists of 3 bases and there are 5 different kinds of bases in a nucleic acid altogether. How many codon will be there?


644) If a DNA has 5000 base pair, and amount of adenine is 15% then find out the number of nucleotides of guanine.


645) We cannot predict the correct sequence of m-RNA from sequence of amino acid. It is due to which property of genetic code.


646) If more than one variant occurs at a locus in human population with a frequency greater than 0.01. It will usually form.


647) In Lac operon which of the following regulates the switching on and off of the operon?


648) Which of the following is ood in reference of genetic code?


649) Which of the following are correct sequence of techniques used during DNA finger printing?
I. Gel electrophoresis
II. Southern blotting
III. Cell fractionation
IV. Autoradiography


650) If 4 types of nitrogenous base are present in nucleic acid, genetic code pentaplets. What is the possible number of base substitutions in total codon?


651) A recent report in the journal nature indicated that there are only 25,000 gene in humans. However, it is likely that there are more than 25,000 different proteins made in humans. A possible explanation for this is


652) What is the size of microsatellite DNAs used as VNTRs?


653) Among the organisms given below choose the organism whose genes have not been sequenced.


654) Which information promises to revolutionise the process of finding chromosomal locations for diseases associated sequence and tracing human history?


655) Two identical twins will not have same


656) Which of the following is required as inducer(s) for the expression of Lac operon?


657) Which of the following is not required for any of the techniques of DNA fingerprinting available at present?


658) Which one of the following is the starter codon?


659) Taylor conducted the experiment to prove semiconservative mode of chromosome replication on


660) The equivalent of a structural gene is


661) Which of the following rRNAs acts as structural RNA as well as ribozyme in bacteria?


662) DNA-dependent RNA polymerase catalyzes transcription on one stand of the DNA which is called the


663) Nucleosome core is intimately associated with


664) The enzyme, which helps to cut one strand of DNA duplex to release tension of coiling of two strands is


665) Which of the following amino acid is coded by a single codon?


666) Initiation of DNA strand synthesis is performed by


667) The following is not a character of RNA


668) The branch of science that uses computer methods in the studies of genomes is called as


669) Who proved experimentally that DNA is genetic material?


670) The fact that the genetic code is almost universal in living organisms is considered to be evidence that all organisms


671) A cell is grown in a solution containing radioactive nucleotides, so that its DNA is labelled with radioactivity. It is removed from the radioactive solution and grown in a normal medium, so that any new DNA strands it makes will not be radioactive. In the normal medium, the cell replicates its DNA and divides. The two daughter cells also replicate their DNA and divide, producing a total of four cells. If a dotted line represents a radioactive DNA strand and a solid line represents a nonradioactive DNA strand, which of the following depicts the DNA of the four cells?


672) An mRNA template is


673) A free transfer RNA molecule can combine with


674) If each amino acid weighs 100 mass units, what is the weight (in mass units) of the protein, molecule synthesised from a mRNA molecule which is 600 bases long?


675) A shorthand method of representing part of a single strand of DNA is shown opposite.
Which of the following shows the correct positions of the phosphate (P), sugar (S) and base (B) molecules?


676) Listed below are the stages in the cellular synthesis of a protein.
1. Movement of mRNA from nucleus to cytoplasm.
2. Linking of adjacent amino acid molecules.
3. Transcription of mRNA from a DNA template.
4. Fromation of the polypeptide chain.
5. Attachment of the mRNA strand to a ribosome.
In which order do these stages take place?


677) The following events occur in the replication of DNA.
1. Bonds between complementary bases break.
2. Bonds between complementary bases form.
3. DNA molecule uncoils.
4. Opposite strands separate.
5. Sugar-phosphate bonds form.
6. Free nucleotides align with complementary nucleotides on each strand.
In which order do these events take place?


678) An mRNA codon for the amino acid alanine is GCC.
How many alanine molecules are present in the polypeptide, containing eight amino acids, coded for by the following DN template?
T C G G C C T A C C G G G C C C A T G C C A A T


679) Find the number of phosphodiester bonds and glycosidic linkages associated with E. coli DNA respectively


680) Three types of RNA involved in comparising the structural and functional role for protein synthesis, serving as a template for translation, and transporting amino acid, respectively are


681) Frederick Griffith conducted experiments testing the virulence of two strains of Streptococcus (R - strain and S-strain). His experiment has 4 specific 'treatments' to it.
Treatment 1, he injected mice with the R-strain and the mice lived.
Treatment 2, he injected mice with the S-strain and the mice died.
Treatment 3, he injected mice with heat-killed S-strain and the mice lived.
Treatment 4, he injected mice with heat-killed S-strain and the mice died.
Which treatment in his experiment is considered a control treatment?


682) Frederick Griffith conducted experiments testing the virulence of two strains of Streptococcus (R - strain and S-strain). His experiment has 4 specific 'treatments' to it.
Treatment 1, he injected mice with the R-strain and the mice lived.
Treatment 2, he injected mice with the S-strain and the mice died.
Treatment 3, he injected mice with heat-killed S-strain and the mice lived.
Treatment 4, he injected mice with heat-killed S-strain mixed with R-strain and the mice died.
Which treatment in his experiment is considered the experimental treatment?


683) Why are mice killed by smooth (S) strains of Streptococcus, but not rough (R) strains?


684) If a researcher added a polymer of synthetic DNA that contained only adenine (A) residues to a reaction containing RNA polymerase and ribonucleotide monomers. What base would be found in the RNA polymer produced?


685) Which of the following statements is correct?
I. The biochemical nature of genetic material was not defined from the experiments conducted by Griffith.
II. Working on transformation Avery et al concluded DNA is genetic material but not all biologists were convinced.
III. RNA is the genetic material in TMV, QB bacteriophage etc.
IV. DNA is the predominant genetic material while RNA performs dynamic functions of messenger and adapter.
V. Viruses having DNA genome and having shorter life span and evolve faster.


686) The prediction of sequence of amino acid is ____A____ if the sequence of nucleotides of mRNA is known. The prediction of sequence of nucleotide is concerned mRNA is ____B____ because the genetic code is ____C____.


687) A very low level of expression of lac operon has to be present in the cell all the time, otherwise


688) Which one is false?


689) The Okazaki fragments in DNA chain growth


690) The length of DNA molecule greatly exceeds the dimensions of the nucleus in the eukaryotic cells. How is this DNA accomodated?


691) A codon consists of three bases and there are four kinds of bases in a nucleic acid altogether. How many codons will be there?


692) The year 2003 was celebrated as the 50th anniversary of discovery of


693) The sequence of structural gene in lac operon is


694) The length of DNA has 45000 base pairs. How many complete turns will the DNA molecule take?


695) Go through the following facts -
I. 'AAG' always codes for lysine. It cannot code for any other amino acid.
II. Serine amino acid can be coded by UCU/UCC/UCA or UCG.
III. UUU forms phenyl alanine in bacteria as well as human beings.
IV. UUU GGG CCC AAAAAC codes for five amino acids.
Now point out nature of genetic code after reading above.


696) A DNA sequence is polymorphic if


697) An RFLP is a


698) Tailoring of hnRNA is done by


699) Which of the following are used in DNA profiling?


700) DNA profiling has been used to


701) Which of the following has the longest DNA sequences?


702) Following paragraph refers to a transcription unit. Fill up the blanks - The ____A____ is located towards 5' end ____B____ of the structural gene (the reference is made with respect to the polarity of coding strand). Both the strands of DNA are involved in forming the _____C_____. The ____D____ is located towards 3' end (_____E_____) of the coding strand.


703) Which one is correct?


704) The full form of ELSI is


705) DNA fingerprinting works because


706) Which of the following criteria must be fulfilled by a genetic material


707) Given below are two statements (A and B) each with two blanks.
Select the option which correctly fill up the blanks in two statements - Statements :
A. Use of radioactive thymidine to detect distribution of newly synthesised DNA in the chromosomes was performed on Vicia faba (faba beans) by ____1____ and colleagues in 1958. The experiment proved that the DNA in chromosomes also replicates ____2____.
B. The chemical method developed by Har Gobind Khorana was instrumental synthesising RNA molecules with defined combinations of bases (homopolymers and copolymers). ___1___ cell-free system for protein synthesis finally helped the code to be deciphered. Severo Ochoa enzyme (polynucleotide phosphorylase) was also helpful in polymerising RNA with defined sequence in a ____2____ independent manner (enzymatic synthesis of RNA).


708) The nitrogenous bases (and the two strands of the DNA double helix) are held together by


709) The base-paired structure of DNA implies that it


710) Why must RNA be incorporated into the DNA molecule initially during DNA replication


711) What ate the three major properties of genes that are explained by the structure of DNA?


712) Semi-conservatie replication of DNA involves


713) The molecules that function to replicate DNA in the cell are


714) The correct order of events for synthesis of the lagging strand is


715) During replication, the new DNA strand is synthesized


716) Why were fragments like those now called Okazaki fragments expected before they were discovered?


717) DNA replication in eukaryotes differs from replication in bacteria because


718) Which statement is incorrect for asymmetric karyotype?


719) In eukaryotes, Okazaki fragments are about __________ long.


720) Which of the following molecules functions to transfer information from one generation to the next?


721) Mutations are


722) In order to show that DNA is the "transforming principle", Avery, Macleod and McCarty showed that DNA could transform avirulent strains of Pneumococcus. This hypothesis was strengthened by their demonstration that


723) During infection of E. coli cells by bacteriophase T2,


724) Bacteriophage nucleic acids were labelled by carrying out an infection of E. coli cells growing in


725) Information used by Watson and Crick to determine the structure of DNA included


726) Double-stranded DNA looks a little like a ladder that has been twisted into a helix or spiral. The side supports of the ladder are


727) The steps of the ladder are


728) If a double-stranded DNA molecule contains 30% T, how much G does it contain?


729) You have analyzed the DNA isolated from a newly discovered virus and found that its base composition is 32% A, 17% C, 32% G, and 19% T. What would be a reasonable explanation of this observation?


730) The number of glycosidic bonds associated with DNA of diploid human cell are


731) During DNA replication


732) The enzyme DNA ligase is required continuously during DNA replication because


733) In DNA replication each newly made strand is


734) Which feature of the Watson-Crick model of DNA structure explains its ability to function in replication and gene expression?


735) The Hershey-Chase experiment convinced most scientists that


736) Which of the following features summarizes the molecular architecture of DNA?


737) The fidelity of DNA replication is outstanding. During DNA synthesis, the error rate is of the order of one wrong nucleotide per


738) Chargaff's rule states that


739) The first scientist(s) to suggest a mode of replication for DNA was (were)


740) In eukaryotic cells, each chromosome has


741) When adding the next monomer to a growing DNA strand, the monomer is added to the


742) The energy necessary for making a DNA molecule comes directly from the


743) A deoxyribose nucleotide is a


744) Synthesis of DNA is


745) The enzyme that removes the RNA primers is called


746) The enzyme that restores the phosphodiester linkage between adjacent fragments in the lagging strand during DNA replication is


747) The building blocks for a new DNA molecule are


748) The force that holds DNA together in a double helix is


749) The enzyme that unwinds the DNA prior to replication is called


750) The first repair of mistakes made during DNA replication is made by


751) The error rate of changing an incorrect base with another incorrect base during proofreading is


752) The difference between DNA and RNA is that


753) If Hershey and Chase has found "S" in both the pellet and the supernatnat, the conclusion about the nature of DNA replication would be that


754) An alien DNA-like molecule is isolated from the frozen remains of a martian life form that was found beneath the martian polar ice caps. It is found that for every base designated Q, there is 2 times the amount of the base R, and for every base Z there is 2 times the amount of the base designated S. If the molecule contains 12% R, how much Z would you expect?


755) Complete genome of which non-crop and crop plants has been sequenced?


756) Number of base pairs in DNA helix around the octamer histone molecule is


757) Pyrophosphate is a


758) Which one of the following is not found in DNA?


759) Boiling DNA causes it to become


760) What was most remarkable about the Griffith's experiment?


761) The Hershey-Chase experiment


762) Griffith could distinguish the two strains of pneumococcus due to


763) When bands of RNA are transferred to a nitrocellulose membrane for identification, the blotting is called


764) In PCR, it is _________ that creates single-stranded template molecules


765) Ideally, PCR __________ increases the amount of DNA during additional cycles


766) Griffith's experiment showing the transformation of R strain Pneumococcus bacteria to S strain Pneumococcus bacteria in the presence of heat-killed S strain bacteria gave evidence that


767) Experiments by Avery, Macleod, and McCarty supported DNA as the genetic material by showing that


768) X-ray crystallography provides information about the __________ of DNA but is limited because of the ________ of DNA. The technique is based on the pattern of __________ of the atoms in the molecule.


769) Chargaff's rules of base pairing state that


770) Watson and Cricks model allowed them to visualize


771) A fundamental requirement for the function of genetic material is that it must be


772) Evidence indicating that DNA replication was semi-conservative came from


773) What are the mini-satellites?


774) The primary function of DNA polymerase is to


775) In gel-electrophoresis, all the DNA fragments move towards the base of the gel with variable velocities because


776) Statement I : Cistron is functional unit of DNA.
Statement II : House keeping genes constantly operate for cellular activity.
Statement III : mRNA coded language is known as cryptogram


777) Proofreading and repair occur


778) DNA replication is an ________ process and _______ energy.


779) T. aquaticus DNA polymerase is not denatured during the heat cycling required to denature DNA. This property allowed advances in what technique?


780) Thirty percent of the bases in a sample DNA extracted from eukaryotic cells is adenine. What percentage of cytosine is present in this DNA?


781) Which of the following represents a bond between a purine and a pyrimidine (in that order)?


782) Which of the following statements about DNA replication is false?


783) Which of the following would not be found in a DNA molecule?


784) If a nucleotide lacking a hydroxyl group at the 3' end is added to a PCR, what would be the outcome?


785) To show that DNA in cell extracts was responsible for genetic transformation in Pneumococcus, important corroborating evidence was that


786) In the Hershey-Chase experiment


787) Which statement about complementary base pairing is not true?


788) Western Blot hybridization is used for


789) Which of the following is not required for DNA replication?


790) The 3' end of a DNA strand is defined as the place were


791) The leading strand and lagging strand in DNA replication differ in that only on the lagging strand


792) The polymerase chain reaction


793) What will be the effect if both the DNA strands can be copied in transcription


794) Which of the following Mendel's law has not been proved to be true in all cases ?


795) Which of the following blood groups is a universal donor ?


796) Identical twins come from :