DNA

Q.

If Adenine makes 30% of the DNA molecule, what will be the percentage of Thymine, Guanine and Cytosine in it?

1. T : 20 ; G : 30 ; C : 20

2. T : 20 ; G : 20 ; C : 30

3. T : 20 ; G : 25 ; C : 25

4. T : 30 ; G : 20 ; C : 20

Q.

The two strands in DNA are not identieal but are complementary. Explain.

Q. Why essential amino acids are not synthesized in the body?

Q.

The internal (cellular) energy reserve in autotrophs is

1. Glycogen

2. Protein

3. Starch

4. Fatty acid

Q.

The two strands in DNA are not identical but are complementary. Explain.

Q. If the total amount of adenine and thymine in a double-stranded DNA is 60%, then the amount of guanine in this DNA will be

1. 30%
2. 40%
3. 15%
4. 20%

Q.

The amino acid which are synthesized in the body are known as:

1. Natural

2. Essential

3. Non-essential

4. Artificial

Q. Which of the following bases are not present in DNA?

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

Q. Amino acids are organic compounds that contain amino and carboxylic groups. In the form of proteins, amino acid residues form the second-largest component of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis.

Which of the following is an amino acid?

1. $H_{2}N-COOH$
2. 
3. 
4. 

Q.

Write the important structural and functional differences between DNA and RNA.

Q. One strand of DNA has sequence of nucleotide 3 ‘ATTCGCTAT 5’ then other strand of DNA has

1. 3 ‘TAGCACGTA 5’
2. 5 ‘TAGCACGTA 3’
3. 3 ‘TAAGCGATA 5’
4. 5 ‘TAAGCGATA 3’

Q. In DNA, the linkages between different nitrogenous bases are

1. phosphate linkage
2. peptide linkage
3. H - bonding
4. glycosidic linkage

Q.

What are the three coding letters in mRNA called?

Q.

Write the structures of fragments produced on complete hydrolysis of DNA. How are they linked in DNA molecule? Draw a diagram to show pairing of nucleotide bases in double helix of DNA.

Q. In both DNA and RNA, heterocyclic base and phosphate ester linkages are at

1. and respectively of the sugar molecule
2. and respectively of the sugar molecule
3. and respectively of the sugar molecule
4. and respectively of the sugar molecule

Q.

Glucose and fructose are:

1. Functional isomers

2. Optical isomers

3. Position isomers

4. Chain isomers

Q.

The central dogma of molecular genetics states that the genetic information flows from:

1. Amino acids $\to$ Proteins $\to$ DNA

2. DNA$\to$ Carbohydrates $\to$ Proteins

3. DNA $\to$ RNA $\to$ Carbohydrates

4. DNA $\to$ RNA $\to$ Proteins

Q. Which of the following amino acid is a non-essential amino acid?

1. Methionine
2. Phenylalanine
3. Tyrosine
4. Tryptophan

Q.

Chargaffs rule is applicable to

1. Single-stranded DNA

2. Single-stranded RNA

3. Double-stranded DNA

4. Double-stranded RNA

Q. The number of hydrogen bonds between Guanine and Cytosine; and between Adenine and Thymine in DNA are:

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

Q.

How many letters are in DNA code?

Q. Amino acids are organic compounds that contain amino and carboxylic groups. In the form of proteins, amino acid residues form the second-largest component of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis.

Consider the following sequence of reaction for production of an alpha amino acid. The amino acid formed is:

1. $H_{2}N-C{H}_2-COOH$
2. 
3. 
4. 

Q. Amino acids are organic compounds that contain amino and carboxylic groups. In the form of proteins, amino acid residues form the second-largest component of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis.

Serine $\left(HOC{H}_{2}CH\right(N{H}_2\left)COOH\right)$ is an essential amino acid. The correct Fisher projection od serine is:

1. 
2. 
3. 
4. 

Q. Which is the nitrogenous base present only in RNA, but not in DNA?

Q.

Why are complementary single strands called sticky ends?

Q.

Which of the following bases is not present in DNA?
(a) Adenine (b) Thymine (c) Cytosine (d) Uracil

Q. What is DNA and 5 to 3 in DNA ? Explain with figure? Draw the structure of all 20 amino acid. How to draw cyclic structure of carbohydrates?

Q. Why is DNA called polynucleotide?

Q.

The chemical formula of gypsum is:

1. MgSO₄.7H₂O

2. BaSO₄

3. CaSO₄.2H₂O

4. KCl

Q. An organic compound (A) having molecular formula C9H10O forms orange-red ppt (B) with the 2, 4-DNP reagent. Compound (A) gives yellow ppt (C) when heated in the presence of iodine and NaOH along with a colorless compound (D). (A) does not reduce Tollens reagent or Fehlings solution nor does it decolorize the Br2 water. On drastic oxidation of (A) with chromic acid, carboxylic acid (E) of molecular formula C7H6O2 is formed. Identify A to E