Nucleotides

Q.

Under which of the following conditions will there be no change in the reading frame of following mRNA?

5’AACAGCGGUGCUAUU3’

1. Deletion of GGU from 7th, 8th, and 9th positions

2. Insertion of G at 5th position

3. Deletion of G from 5th position

4. Insertion of A and G at 4th and 5th positions, respectively

Q.

Two nucleotides are linked through

1. 3' - 2' Phosphodiester bond

2. 5' - 3' Phosphodiester bond

3. 3' - 5' Phosphodiester bond

4. 2' - 3' Phosphodiester bond

Q. Chargaff's rule states that in an organism:

1. Amount of adenine (A) is equal to that of cytosine (C) and the amount of thymine (T) is equal to that of guanine (G)
2. Amount of all bases is equal
3. Amount of adenine (A) is equal to that of thymine (T) and the amount of guanine (G) is equal to that of cytosine (C)
4. Amount of adenine (A) is equal to that of guanine (G) and the amount of thymine (T) is equal to that of cytosine (C)

Q.

Dinucleotide is obtained by joining two nucleotides together by a phosphodiester linkage. Between which carbon atoms of pentose sugars of nucleotides are these linkages present?
(a) 5' and 3' (b) 1' and 5' (c) 5' and 5' (d) 3' and 3'

Q. A segment of DNA has 120 adenine and 120 cytosine bases. The total number of nucleotides present in the segment is:

1. 120
2. 480
3. 240
4. 360

Q. 7.How to find peroxy linkage in K3CrO8 without drawing structure

Q.

Dinucleotide is obtained by joining two nucleotides together by phosphodiester linkage. Between which carbon of pentose sugar of nucleotides are these linkages present?

1. 5' and 3'

2. 1' and 5'

3. 5' and 5'

4. 3' and 3'

Q.

In nucleoside, a base is attached at 1' position of sugar moiety. Nucleotide is formed by linking of phosphotic acid unit to the sugar unit of nucleoside. At which position of sugar unit is the phosphoric acid linked in a nucleoside to give a nucleotide?

Q.

Which moieties of nucleosides are involved in the formation of phosphodiester linkages present in dinucleotides? What does the word diester in the name of linkage indicate? Which acid is involved in the formation of this linkage?

Q. Which general formula below represents that of an organic ester?

1. $R-OH$
2. $R-COOH$
3. $R-O-R$
4. $R-COO-R$
5. $R-CO-R$

Q.

Chargaff's rule states that in an organism

[CBSE PMT 2003]

1. Amounts of all bases are equal

2. Amount of adenine (A) is equal to that of thymine (T) and the amount of guanine (G) is equal to that of cytosine (C)

3. Amount of adenine (A) is equal to that of guanine (G) and the amount of thymine (T) is equal to that of cytosine (C)

4. Amount of adenine (A) is equal to that of cytosine (C) and the amount of thymine (T) is equal to guanine (G)

Q. Purine derivative among the following bases is

1. Cytosine
2. Thymine
3. Guanine
4. Uracil

Q. What is the structure of Perchloro ethane?

Q.

Chargaff's rule states that in an organism

[CBSE PMT 2003]

1. Amounts of all bases are equal

2. Amount of adenine (A) is equal to that of thymine (T) and the amount of guanine (G) is equal to that of cytosine (C)

3. Amount of adenine (A) is equal to that of guanine (G) and the amount of thymine (T) is equal to that of cytosine (C)

4. Amount of adenine (A) is equal to that of cytosine (C) and the amount of thymine (T) is equal to guanine (G)

Q. How many tripeptides can be prepared by linking the amino acids glycine, alamine and phenyl alanine?

1. One
2. Six
3. Three
4. Twelve

Q.

Chargaff's rule states that in an organism

[CBSE PMT 2003]

1. Amounts of all bases are equal

2. Amount of adenine (A) is equal to that of thymine (T) and the amount of guanine (G) is equal to that of cytosine (C)

3. Amount of adenine (A) is equal to that of guanine (G) and the amount of thymine (T) is equal to that of cytosine (C)

4. Amount of adenine (A) is equal to that of cytosine (C) and the amount of thymine (T) is equal to guanine (G)

Q. The functional group present in cytosine are:

1. Keto and amino
2. Keto only
3. Amino only
4. Methyl

Q. How many $S-S$ linkage(s) is/are present in sodium tetrathionate ?

1. 4
2. 3
3. 2
4. 1

Q. Purine derivative among the following bases is

1. Guanine
2. Cytosine
3. Thymine
4. Uracil

Q. A segment of DNA has 120 adenine and 120 cytosine bases. The total number of nucleotides present in the segment is:

1. 120
2. 240
3. 360
4. 480