Classification of Enzymes

Q.

What is the role of HCl in digestion?

Q. Name the type of enzyme involved in the following reaction:
S-G + S’ $\to$ S + S’-G

1. Isomerase
2. Transferase
3. Hydrolase
4. Lyase

Q. In the polynucleotide chain of DNA, a nitrogenous base is linked to the $–OH$ of:

1. 2'C pentose sugar
2. 3'C pentose sugar
3. 5'C pentose sugar
4. 1'C pentose sugar

Q.

Which Bond Is Present Between The Phosphate And Hydroxyl Groups Of Sugar?

Q. Synthesis of histone proteins and tubulin proteins takes place in __A__ and __B__ respectively.

1. A B
   S-phase G${}_1$ phase
2. A B
   G${}_2$ phase S phase
3. A B
   G${}_1$ phase G${}_2$ phase
4. A B
   S phase G${}_2$ phase

Q. Which of the following statements is true with respect to transcription?

1. RNA synthesis always occurs in the 5' - 3' direction
2. RNA polymerase needs a primer to initiate transcription
3. U is inserted in RNA complementary to T in DNA
4. All of these

Q. Intrinsic factor is essential for absorption of

1. vitamin $B_{12}$
2. folic acid
3. proteins
4. extrinsic factor

Q.

Why is succinate dehydrogenase embedded in the mitochondrial membrane?

Q.

Which of the following is the cofactor of carbonic anhydrase?

1. Cu

2. Zn

3. Fe

4. Mg

Q. If the “annealing” step is missed during PCR, what would be its effect on the entire process?
I. DNA strands will not separate
II. Primers will not attach
III. DNA Polymerase would not work
IV. DNA will not extend

1. I & II
2. II, III & IV
3. II only
4. II & IV

Q. What would happen if lysosomes get ruptured in a cell?

1. Cell dies
2. Cell shrinks
3. Cell swell up
4. Nothing would happen

Q.

The main difference in gram positive and gram negative bacteria resides in their :

(1)	Cell envelope
(2)	Flagella
(3)	Cell membrane
(4)	Cell wall

Q. Which of the following is an example of ribozymes?

1. Protease
2. Ribosomes
3. Deoxyribonuclease
4. Ribonuclease P

Q.

During biological nitrogen fixation, inactivation of nitrogenase by oxygen poisoning is prevented by.

1. a) Cytochrome

2. b) Leghaemoglobin

3. c) Xanthophyll

4. d) Carotene

Q.

The sugar moiety present in DNA and RNA is

1. Hexose

2. Triose

3. Pentose

4. Tetrose

Q. PCR involves three different steps with variable temperatures. The step of PCR conducted at the highest temperature causes

1. annealing of the primers
2. separation of the DNA strands
3. synthesis of DNA by Taq DNA polymerase
4. All of these

Q.

Are enzymes destroyed after they react?

Q.

What kind of biomolecule is an enzyme?

Q. Which of the following is not correct for a successful PCR?

1. Thermostable DNA polymerase
2. Nanogram of DNA template
3. Primer with exposed 5'−OH group only
4. dNTPs

Q.

The enzyme lipase is present in _________

Q.

What is a bolus?

Q. Which of the following catalyses the transfer of functional groups from one molecule to another?

1. Ligases
2. Transferases
3. Lyases
4. Hydrolases

Q.

What is the strongest type of interaction between two cysteine amino acids in a protein?

Q. Which one of the following makes use of RNA template to synthesise DNA?

1. DNA ligase
2. DNA dependent RNA polymerase
3. Reverse transcriptase
4. DNA dependent DNA polymerase

Q.

Match the enzyme with their respective substrate and choose the right one among options given
$\begin{array}{cccc}& ColumnI& & ColumnII\\ A.& \text{Lipase}& 1.& \text{Dipeptides}\\ B.& \text{Nuclease}& 2.& \text{Fats}\\ C.& \text{Carboxypeptidase}& 3.& \text{Nucleic acids}\\ D.& \text{Dipeptidases}& 4.& \text{Proteins, peptones and proteoses}\end{array}$
Codes
(a) A-2, B-3, C-1, D-4 (b) A-3, B-4, C-2, D-1
(a) A-3, B-1, C-4, D-2 (d) A-2, B-3, C-4, D-1

Q. Which of the following enzymes are used as the tools of recombinant DNA technology?

1. Restriction enzymes, polymerase enzymes, lipase
2. Restriction enzymes, polymerase enzymes, ligases
3. Restriction enzymes, lipase, ligases
4. Restriction enzymes, polymerase enzymes, esterase
   

Q. Study the graph given below and name the three phases of PCR indicated by 1, 2 and 3.

1. 1-Annealing, 2-Renaturation,
   3-Extension
2. 1-Renaturation, 2-Annealing,
   3-Extension
3. 1-Denaturation, 2-Renaturation,
   3-Annealing
4. 1-Denaturation, 2-Annealing,
   3-Extension

Q. Molecular scissors, which cut DNA at specific sites are known as __________.

1. DNA polymerases
2. DNA ligases
3. RNA polymerases
4. restriction enzymes

Q. Which of the following enzyme(s) is/are an exception to the rules laid down for naming of enzymes?

1. Trypsin
2. ATPase
3. ATP synthase
4. Amylase

Q. Select the incorrect statement about dNTPs.

1. These serve as energy sources for polymerisation reactions
2. These serve as substrates for DNA polymerase
3. These act as enzymes to catalyze the DNA replication process
4. Both a and b are correct