Tag: structure of chromosome, cell cycle and cell division
Questions Related to structure of chromosome, cell cycle and cell division
If there are 10,000 base pairs in DNA, then its length
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340 nm
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3400 nm
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34000 nm
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340000 nm
According to the most widely accepted model of DNA structure, the distance between any two base pairs in DNA is approximately 3.4 angstroms. Thus for a DNA molecule having 10,000 base pairs; the length will be 10,000 x 3.4 or 34000 angstroms or 3400 nanometers.
So, the correct answer is option B.
In a DNA sample the proportion of A is 17%, the amount of G + T and C will be respectively.
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50% and 33%
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66% and 17%
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66% and 33%
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33% and 50%
In any double stranded DNA, adenine (A) pairs with a thymine (T) and Guanine (G) pairs with a cytosine (C).
Now, since each A always pairs with a T, the percentage of A and T will always be the same. Therefore, percentage of T will also be 17%.
So we can conclude that A+T=17+17=34%
The rest would account for G+C which would be 100-34=66%, thus G+C=66%.
The eukaryotic chromosome contains nucleosome spools.
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True
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False
How many amino acids will be coded by the given sequence of ribonucleotides, if the 15$^{th}$ base is substituted by G?
'5AUGGUGUAGAGGUACCAU3'
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Four
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Five
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Six
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Two
Amino acid synthesis stops when any STOP codon is encountered by ribosome. There are total 3 stop codons, UAG, UGA, UAA. Codons are always read in triplets. So the given ribonucleotide sequence will be read as: AUG,GUG, UAG, and so on. Notice that the third codon (UAG) is a stop codon, so the protein synthesis will stop at the third codon itself. It doesn't matter if the 15th base is substituted by G or not, the given sequence will code for only two amino acids, AUG (methionine) and GUG (Methionine)
DNA cannot pass through a cell membrane as
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It is too big to cross the membrane
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It is a hydrophilic molecule
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Membrane does not have specific proteins to facilitate the transport
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None of these
DNA cannot pass through a cell membrane as it is hydrophilic in nature whereas cell membrane is made up of lipid bilayer.
Feulgen test, is unique for DNA, is a
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Gentian violet
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Neutral red
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Basic fuchsin
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Cotton blue
- The feulgen test is a staining technique discovered by Robert Feulgen and used in histology to identify chromosomal material or DNA in cell specimens.
- The Feulgen test, is unique for DNA, is a Basic Fuchsin.
- It is used for demonstration of DNA (deoxyribonucleic acid) in tissue sections.
- So, the correct answer is 'Basic fuchsin',
Bonding between deoxyribose and base in pyrimidine nucleoside molecule is :-
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$1'-1'$ glycosidic linkage
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$1'-6'$ glycosidic linkage
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$1'-9'$ glycosidic linkage
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$1'-4'$ glycosidic linkage
Bonding between deoxyribose and base in pyrimidine nucleoside molecule is $1'-1'$ glycosidic linkage because
Which of the following is not related to Watson and Crick model of DNA?
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X-ray crystallography
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The Meselson-Stahl experiment
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Chargaff's rules
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The different sizes of purines and pyrimidines
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The transforming principle of Avery et al
Meselson-Stahl experiment - DNA Replication is Semiconservative.
So, the correct answer is option E.