Replication transcription translation

1. During replication of DNA, which one of the following enzymes polymerizes the Okazaki fragments?

1. DNA Polymerase I

2. DNA Polymerase II

3. DNA Polymerase III

4. RNA Polymerase I

2. A nucleic acid was analyzed and found to contain 32% adenine, 18% guanine, 17% cytosine and 33% thymine. The nucleic acid must be:

1. Single-stranded RNA

2. Single-stranded DNA.

3. Double—stranded RNA

4. Double stranded DNA

3. A nucleotide consists of

1. A sugar, a base and a phosphate

2. A sugar and a phosphate

3. Paired bases

4. A sugar, a base and three phosphates

4. Which of the following is a purine?

1. Cytosine

2. Adenine

3. Thymine

4. Uracil

5. ATP is from which general category of molecules?

1. Polysaccharides

2. Proteins

3. Nucleotides

4. Amino acids

6. The accepted hypothesis for DNA replication is

1. Conservative theory

2. Dispersive theory

3. Semi-conservative theory

4. Evolutionary theory

7. When DNA polymerase is in contact with guanine in the parental strand, what does it add to the growing daughter strand?

1. Phosphate

2. Cytosine

3. Uracil

4. Guanine

8. In DNA double helix, the two DNA chains are held together by

1. Covalent bonds between the pair of bases

2. Hydrogen bonds between the pair of bases

3. Ionic bonds between the pair of bases

4. None of the above

9. Which of the following enzyme adds complementary bases during replication?

1. Helicase

2. Synthesase

3. Replicase

4. Polymerase

10. The sigma subunit of prokaryotic RNA polymerase:

1. Binds the antibiotic Rifampicin

2. Is inhibited by -amanitin

3. Specifically recognizes the promoter site

4. Is part of the core enzyme

11. The regulatory step in biosynthesis of pyrimidine is catalysed by

a) Dihydroorotase

b) Aspartatetranscarbamylase

c) Dihydroorotatedehydrogenase

d) Carbamoylphosphatesynthetase

12. During replication of DNA, which one of the following enzymes polymerizes the Okazaki fragments?

a) DNA Polymerase I

b) DNA Polymerase II

c) DNA Polymerase III

d) RNA Polymerase I

13. The enzyme DNA ligase

a) Introduces super helical twists

b) Connects the end of two DNA chains

c) Unwinds the double helix

d) Synthesis’s RNA primers

14. Nucleoside is a pyrimidine or purine base

a) Covalently bonded to a sugar

b) Ionically bonded to a sugar

c) Hydrogen bonded to a sugar

d) None of the above

15. The glycosidic bonds in DNA and RNA

a) Connect the sugar to the base

b) Can be hydrolyzed by OH- ion

c) Stabilize Watson-Crick H-bonds

d) Is free to rotate over about 180°

16. In a double stranded molecule of DNA, the ratio of purines: pyrimidines is:

a) Variable

b) Determined by the base sequence in RNA

c) Genetically determined

d) Always 1:1

17. A patient has Lesch-Nyhan syndrome caused by an absence of hypoxanthine-guanine phosphoribosyltransferase. The patient's condition is caused by an enzyme deficiency in which of the following biochemical pathways?

a) Ganglioside metabolism

b) Monosaccharide

c) Purine metabolism

d) Pyrimidine metabolism

18. The step of protein synthesis in which the information contained specific segment of DNA is copied into RNA is called

a) Transduction

b) Translation

c) Transformation

d) Transcription