Molecular Basis of Inheritance

In an inducible operon, the genes are :

1. usually expressed unless a signal turns them "off"
2. always expressed
3. never expressed
4. usually not expressed unless a signal turns them "on"

One of the most frequently used techniques in DNA fingerprinting is :-

1. SSCP
2. SCAR
3. VNTR
4. AFLP

Read the following four statements (A-D) : How many of the above statements are right ?

1. Four
2. Two
3. Three
4. One

What is it that forms the basis of DNA Fingerprinting ?

1. The relative proportions of purines and pyrimidines in DNA
2. The relative amount of DNA in the ridges and grooves of the fingerprints
3. The relative difference in the DNA occurrence in blood, skin and saliva
4. Satellite DNA occurring as highly repeated short DNA segments

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

1. Looping
2. Inducing
3. Slicing
4. Splicing

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

1. ATCGU
2. UAGAC
3. AACTG
4. TTAGU

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

1. The structural gene
2. The inducer
3. A terminator
4. A promoter

Removal of RNA polymerase-III from nucleoplasm will affect the synthesis of

1. tRNA
2. hnRNA
3. rRNA
4. mRNA

PCR and Restriction Fragment Length Polymorphism are the methods for

1. Genetic transformation
2. Genetic fingerprinting
3. Study of enzymes
4. DNA sequencing

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

1. Viroid
2. Bacterium
3. Fungus
4. Bacterial virus

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

1. 5S rRNA
2. snRNA
3. hnRNA
4. 23S rRNA

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

1. Nucleosomes
2. Genes
3. Nucleotides
4. Base pairs

The 3'-5' phosphodiester linkages inside a polynucleotide chain serve to join -

1. One nucleotide with another nucleotide
2. One nitrogenous base with pentose sugar
3. One nucleoside with another nucleoside
4. One DNA strand with the other DNA strand

The lac operon consists of -

1. Three regulatory genes and three structural genes
2. Four regulatory genes only
3. Two regulatory genes and two structural genes
4. One regulatory gene and three structural genes

In eukaryotic cell transcription, RNA splicing and RNA capping take place inside the -

1. Dictyosomes
2. Ribosomes
3. Nucleus
4. ER

Which one of the following statements about the particular entity is true?

1. Nucleosome is formed of nucleotides
2. Centromere is found in animal cells, which produces aster during cell division
3. The gene for producing insulin is present in every body cell
4. DNA consists of a core of eight histones

Which one of the following does not follow the central dogma of molecular biology ?

1. Mucor
2. HIV
3. Chlamydomonas
4. Pea

The one aspect which is not a salient feature of genetic code, is its being –

1. Specific
2. Degenerate
3. Ambiguous
4. Universal

Select the two correct statements out of the four (A–D) statements given below about lac operon. The correct statements are :

1. B and D
2. A and B
3. B and C
4. A and C

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

1. Nirenberg and Matthaei
2. Morgan and Sturtevant
3. Hershey and Chase
4. Beadle and Tatum

Semi-conservative replication of DNA was first demonstrated in:

1. Drosophila melanogaster
2. Streptococcus pneumoniae
3. Salmonella typhimurium
4. Escherichia coli

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

1. Transformation
2. Capping
3. Splicing
4. Tailing

What is not true for genetic code?

1. It is nearly universal
2. A codon in mRNA is read in a noncontiguous fashion
3. It is degenerate
4. It is unambiguous

In the DNA molecule:

1. the total amount of purine nucleotides and pyrimidine nucleotides is not always equal
2. there are two strands which run antiparallel one in 5' 3' direction and other in 3' 5'
3. there are two strands which run parallel in the 5' 3' direction
4. the proportion of adenine in relation to thymine varies with the organism

Which one of the following pairs of nitrogenous bases of nucleic acids is wrongly matched with the category mentioned against it?

1. Thymine, Uracil — Pyrimidines
2. Guanine, Adenine — Purines
3. Uracil, Cytosine — Pyrimidines
4. Adenine, Thymine — Purines

Which one of the following pairs of codons is correctly matched with their function or the signal for the particular amino acid?

1. UUA, UCA — Leucine
2. AUG, ACG — Start/Methionine
3. UAG, UGA — Stop
4. GUU, GCU — Alanine

One turn of the helix in a B-form DNA is approximately -

1. 20 nm
2. 3.4 nm
3. 2 nm
4. 0.34 nm

One gene-one enzyme hypothesis was postulated by -

1. A. Garrod
2. Hershey and Chase
3. Beadle and Tatum
4. R. Franklin

Antiparallel strands of a DNA molecule means that-

1. The phosphate groups at the start of two DNA strands are in opposite position (pole)
2. One strand turns anti-clockwise
3. One strand turns clockwise
4. The phosphate groups of two DNA strands, at their ends, share the same position

Which antibiotic inhibits interaction between tRNA and mRNA during bacterial protein synthesis?

1. Neomycin
2. Erythromycin
3. Tetracycline
4. Streptomycin