166188
One turn of the helix in a B-form DNA is approximately-
1 \(20 \mathrm{~nm}\)
2 \(0.34 \mathrm{~nm}\)
3 \(3.4 \mathrm{~nm}\)
4 \(2 \mathrm{~nm}\)
Explanation:
B-form of DNA shows right handed coiling which contains 10 base pairs in each turn. One complete turn of DNA occupies \(34 \AA\) distance. So, in \(\mathrm{nm}\) it will \(3.4 \mathrm{~nm}\) because \(\begin{aligned} & 1 \mathrm{~nm}=10^{-9} \mathrm{~m} \\ & 1 \AA=10^{-10} \mathrm{~m} \\ & 34 \AA=34 \times 10^{-10} \mathrm{~m} \\ & \text { or }=3.4 \times 10^{-9} \mathrm{~m} \\ & \text { so }=3.4 \mathrm{~nm} \end{aligned}\)
AIPMT-2006
Molecular Basis of Inheritance and
166189
Nucleotides are building blocks of nucleic acids. Each nucleotide is a composite molecule formed by -
1 Base-sugar-OH
2 Base-sugar-phosphate
3 Sugar-phosphate
4 (Base-sugar-phosphate)
Explanation:
Each nucleotide consist of : (i) a nitrogenous heterocyclic base which may be purine or pyrimidine. (ii) Sugar (deoxyribose in DNA, ribose in RNA) (iii) Phosphate group. Nucleotides are organic molecules that serve as the monomers or subunits of nucleic acids like DNA and RNA. - Nucleoside = Sugar + base (via glycosidic bond) - Nucleotide \(=\) Nucleoside + Phosphate (via phospho diester bond)
AIPMT-2005
Molecular Basis of Inheritance and
166193
In DNA \(20 \%\) bases are adenine. What percentage of bases are pyrimidines?
1 \(30 \%\)
2 \(60 \%\)
3 \(50 \%\)
4 \(20 \%\)
Explanation:
According to Chargaff's rule \(\begin{array}{ll} & \mathrm{A}+\mathrm{G}=\mathrm{C}+\mathrm{T}=50 \% \\ \therefore \text { If } \quad & \mathrm{A}=20 \% \text { then } \mathrm{T}=20 \% \\ \mathrm{C}+\mathrm{T}=50 \% \\ \mathrm{C}=50 \% & -20 \%=30 \% \end{array}\) Total percentage of pyrimidine bases \((\mathrm{T}+\mathrm{C}) \text { are } 20+30=50 \%\)
JIPMER-2019
Molecular Basis of Inheritance and
166201
The length of DNA helix in a typical nucleosome is
1 \(200 \mathrm{bp}\)
2 \(1000 \mathrm{bp}\)
3 \(3.2 \times 10^{6} \mathrm{bp}\)
4 \(6.6 \times 10^{9} \mathrm{bp}\)
Explanation:
The length of DNA helix in a typical nucleosome is \(200 \mathrm{bp}\) approximately. The negatively charged DNA is wrapped around the positively charged histone octamer to form nucleosome. - A nucleosome contains: - 200 bp of DNA - two copies of each core histone \((\mathrm{H} 2 \mathrm{~A}, \mathrm{H} 2 \mathrm{~B}, \mathrm{H} 3\), and \(\mathrm{H} 4\) )
166188
One turn of the helix in a B-form DNA is approximately-
1 \(20 \mathrm{~nm}\)
2 \(0.34 \mathrm{~nm}\)
3 \(3.4 \mathrm{~nm}\)
4 \(2 \mathrm{~nm}\)
Explanation:
B-form of DNA shows right handed coiling which contains 10 base pairs in each turn. One complete turn of DNA occupies \(34 \AA\) distance. So, in \(\mathrm{nm}\) it will \(3.4 \mathrm{~nm}\) because \(\begin{aligned} & 1 \mathrm{~nm}=10^{-9} \mathrm{~m} \\ & 1 \AA=10^{-10} \mathrm{~m} \\ & 34 \AA=34 \times 10^{-10} \mathrm{~m} \\ & \text { or }=3.4 \times 10^{-9} \mathrm{~m} \\ & \text { so }=3.4 \mathrm{~nm} \end{aligned}\)
AIPMT-2006
Molecular Basis of Inheritance and
166189
Nucleotides are building blocks of nucleic acids. Each nucleotide is a composite molecule formed by -
1 Base-sugar-OH
2 Base-sugar-phosphate
3 Sugar-phosphate
4 (Base-sugar-phosphate)
Explanation:
Each nucleotide consist of : (i) a nitrogenous heterocyclic base which may be purine or pyrimidine. (ii) Sugar (deoxyribose in DNA, ribose in RNA) (iii) Phosphate group. Nucleotides are organic molecules that serve as the monomers or subunits of nucleic acids like DNA and RNA. - Nucleoside = Sugar + base (via glycosidic bond) - Nucleotide \(=\) Nucleoside + Phosphate (via phospho diester bond)
AIPMT-2005
Molecular Basis of Inheritance and
166193
In DNA \(20 \%\) bases are adenine. What percentage of bases are pyrimidines?
1 \(30 \%\)
2 \(60 \%\)
3 \(50 \%\)
4 \(20 \%\)
Explanation:
According to Chargaff's rule \(\begin{array}{ll} & \mathrm{A}+\mathrm{G}=\mathrm{C}+\mathrm{T}=50 \% \\ \therefore \text { If } \quad & \mathrm{A}=20 \% \text { then } \mathrm{T}=20 \% \\ \mathrm{C}+\mathrm{T}=50 \% \\ \mathrm{C}=50 \% & -20 \%=30 \% \end{array}\) Total percentage of pyrimidine bases \((\mathrm{T}+\mathrm{C}) \text { are } 20+30=50 \%\)
JIPMER-2019
Molecular Basis of Inheritance and
166201
The length of DNA helix in a typical nucleosome is
1 \(200 \mathrm{bp}\)
2 \(1000 \mathrm{bp}\)
3 \(3.2 \times 10^{6} \mathrm{bp}\)
4 \(6.6 \times 10^{9} \mathrm{bp}\)
Explanation:
The length of DNA helix in a typical nucleosome is \(200 \mathrm{bp}\) approximately. The negatively charged DNA is wrapped around the positively charged histone octamer to form nucleosome. - A nucleosome contains: - 200 bp of DNA - two copies of each core histone \((\mathrm{H} 2 \mathrm{~A}, \mathrm{H} 2 \mathrm{~B}, \mathrm{H} 3\), and \(\mathrm{H} 4\) )
166188
One turn of the helix in a B-form DNA is approximately-
1 \(20 \mathrm{~nm}\)
2 \(0.34 \mathrm{~nm}\)
3 \(3.4 \mathrm{~nm}\)
4 \(2 \mathrm{~nm}\)
Explanation:
B-form of DNA shows right handed coiling which contains 10 base pairs in each turn. One complete turn of DNA occupies \(34 \AA\) distance. So, in \(\mathrm{nm}\) it will \(3.4 \mathrm{~nm}\) because \(\begin{aligned} & 1 \mathrm{~nm}=10^{-9} \mathrm{~m} \\ & 1 \AA=10^{-10} \mathrm{~m} \\ & 34 \AA=34 \times 10^{-10} \mathrm{~m} \\ & \text { or }=3.4 \times 10^{-9} \mathrm{~m} \\ & \text { so }=3.4 \mathrm{~nm} \end{aligned}\)
AIPMT-2006
Molecular Basis of Inheritance and
166189
Nucleotides are building blocks of nucleic acids. Each nucleotide is a composite molecule formed by -
1 Base-sugar-OH
2 Base-sugar-phosphate
3 Sugar-phosphate
4 (Base-sugar-phosphate)
Explanation:
Each nucleotide consist of : (i) a nitrogenous heterocyclic base which may be purine or pyrimidine. (ii) Sugar (deoxyribose in DNA, ribose in RNA) (iii) Phosphate group. Nucleotides are organic molecules that serve as the monomers or subunits of nucleic acids like DNA and RNA. - Nucleoside = Sugar + base (via glycosidic bond) - Nucleotide \(=\) Nucleoside + Phosphate (via phospho diester bond)
AIPMT-2005
Molecular Basis of Inheritance and
166193
In DNA \(20 \%\) bases are adenine. What percentage of bases are pyrimidines?
1 \(30 \%\)
2 \(60 \%\)
3 \(50 \%\)
4 \(20 \%\)
Explanation:
According to Chargaff's rule \(\begin{array}{ll} & \mathrm{A}+\mathrm{G}=\mathrm{C}+\mathrm{T}=50 \% \\ \therefore \text { If } \quad & \mathrm{A}=20 \% \text { then } \mathrm{T}=20 \% \\ \mathrm{C}+\mathrm{T}=50 \% \\ \mathrm{C}=50 \% & -20 \%=30 \% \end{array}\) Total percentage of pyrimidine bases \((\mathrm{T}+\mathrm{C}) \text { are } 20+30=50 \%\)
JIPMER-2019
Molecular Basis of Inheritance and
166201
The length of DNA helix in a typical nucleosome is
1 \(200 \mathrm{bp}\)
2 \(1000 \mathrm{bp}\)
3 \(3.2 \times 10^{6} \mathrm{bp}\)
4 \(6.6 \times 10^{9} \mathrm{bp}\)
Explanation:
The length of DNA helix in a typical nucleosome is \(200 \mathrm{bp}\) approximately. The negatively charged DNA is wrapped around the positively charged histone octamer to form nucleosome. - A nucleosome contains: - 200 bp of DNA - two copies of each core histone \((\mathrm{H} 2 \mathrm{~A}, \mathrm{H} 2 \mathrm{~B}, \mathrm{H} 3\), and \(\mathrm{H} 4\) )
NEET Test Series from KOTA - 10 Papers In MS WORD
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Molecular Basis of Inheritance and
166188
One turn of the helix in a B-form DNA is approximately-
1 \(20 \mathrm{~nm}\)
2 \(0.34 \mathrm{~nm}\)
3 \(3.4 \mathrm{~nm}\)
4 \(2 \mathrm{~nm}\)
Explanation:
B-form of DNA shows right handed coiling which contains 10 base pairs in each turn. One complete turn of DNA occupies \(34 \AA\) distance. So, in \(\mathrm{nm}\) it will \(3.4 \mathrm{~nm}\) because \(\begin{aligned} & 1 \mathrm{~nm}=10^{-9} \mathrm{~m} \\ & 1 \AA=10^{-10} \mathrm{~m} \\ & 34 \AA=34 \times 10^{-10} \mathrm{~m} \\ & \text { or }=3.4 \times 10^{-9} \mathrm{~m} \\ & \text { so }=3.4 \mathrm{~nm} \end{aligned}\)
AIPMT-2006
Molecular Basis of Inheritance and
166189
Nucleotides are building blocks of nucleic acids. Each nucleotide is a composite molecule formed by -
1 Base-sugar-OH
2 Base-sugar-phosphate
3 Sugar-phosphate
4 (Base-sugar-phosphate)
Explanation:
Each nucleotide consist of : (i) a nitrogenous heterocyclic base which may be purine or pyrimidine. (ii) Sugar (deoxyribose in DNA, ribose in RNA) (iii) Phosphate group. Nucleotides are organic molecules that serve as the monomers or subunits of nucleic acids like DNA and RNA. - Nucleoside = Sugar + base (via glycosidic bond) - Nucleotide \(=\) Nucleoside + Phosphate (via phospho diester bond)
AIPMT-2005
Molecular Basis of Inheritance and
166193
In DNA \(20 \%\) bases are adenine. What percentage of bases are pyrimidines?
1 \(30 \%\)
2 \(60 \%\)
3 \(50 \%\)
4 \(20 \%\)
Explanation:
According to Chargaff's rule \(\begin{array}{ll} & \mathrm{A}+\mathrm{G}=\mathrm{C}+\mathrm{T}=50 \% \\ \therefore \text { If } \quad & \mathrm{A}=20 \% \text { then } \mathrm{T}=20 \% \\ \mathrm{C}+\mathrm{T}=50 \% \\ \mathrm{C}=50 \% & -20 \%=30 \% \end{array}\) Total percentage of pyrimidine bases \((\mathrm{T}+\mathrm{C}) \text { are } 20+30=50 \%\)
JIPMER-2019
Molecular Basis of Inheritance and
166201
The length of DNA helix in a typical nucleosome is
1 \(200 \mathrm{bp}\)
2 \(1000 \mathrm{bp}\)
3 \(3.2 \times 10^{6} \mathrm{bp}\)
4 \(6.6 \times 10^{9} \mathrm{bp}\)
Explanation:
The length of DNA helix in a typical nucleosome is \(200 \mathrm{bp}\) approximately. The negatively charged DNA is wrapped around the positively charged histone octamer to form nucleosome. - A nucleosome contains: - 200 bp of DNA - two copies of each core histone \((\mathrm{H} 2 \mathrm{~A}, \mathrm{H} 2 \mathrm{~B}, \mathrm{H} 3\), and \(\mathrm{H} 4\) )
