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 :
1. G 17%, A 16.5%,T32.5%
2. G 17%, A 33%,T 33%
3. G8.5%,A50%, T24.5%
4. G 34%,A 24.5%,T 24.5%

Subtopic:  DNA Double Helix |
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The human chromosome with the highest and least number of genes in them are respectively:

1. Chromosome 21 and Y

2. Chromosome 1 and X

3. Chromosome 1 and Y

4. Chromosome X and Y

Subtopic:  Human Genome Project |
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Who amongst the following scientists had no contribution in the development of the double helix model for the structure of DNA?

1. Rosalind Franklin

2. Maurice Wilkins

3. Erwin Chargaff

4. Meselson and Stahl

Subtopic:  The DNA |
 77%
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DNA is a polymer of nucleotides which are linked to each other by 3’-5’ phosphodiester bond. To prevent polymerisation of nucleotides, which of the following modifications would you choose?

1. Replace purine with pyrimidines

2. Remove/Replace 3' OH group in deoxy ribose

3. Remove/Replace 2' OH group with some other group in deoxy ribose

4. Both ‘b’ and ‘c’

Subtopic:  DNA Double Helix |
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A mutation at a gene locus changes a character due to change in
1. DNA replication
2. Protein synthesis pattern
3. RNA transcription pattern
4. Protein structure

Subtopic:  Mutations and Genetic Code |
From NCERT
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Degeneration of genetic code is due to
1. First member of codons
2. Second member of codons
3. Third member of codons
4. Entire codons.

Subtopic:  Genetic Code |
 64%
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In gene mutation, adenine is replaced by guanine. It is
1. Frame-shift mutation
2. Transcription
3. Transition
4. Transversion

Subtopic:  Genetic Code |
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In bacterial DNA replication, synthesis starting from the site of origin of replication
1. Involves RNA primers
2. Requires telomerase
3. Proceeds unidirectionally
4. Moves bidirectionally

Subtopic:  DNA Replication: I |
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On which organism Beadle and Tatum worked to propose one gene-one enzyme hypothesis
1. Drosophila
2. Escherichia coli
3. Neurospora crassa
4. Nostoc

Subtopic:  Translation |
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During transcription, holoenzyme RNA polymerase binds to DNA sequence and DNA assumes a saddle like
structure at that point. The sequence is called
1. AAAT box
2. TATA box
3. GGTT box
4. CAAT box.

Subtopic:  Transcription: I | Transcription:II |
 91%
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