Chapter 2 The Chemistry of Cells ‐‐‐‐‐‐Nucleic Acids The 3rd class Homework I. Definitions 1. Nucleic acids : 2. Phosphodiester bond: II. True or False 1.
The basic unit of nucleic acids is the amino acid. ( ) 2.
tRNA serves as an amino acid carrier to transport amino acid for protein synthesis. ( ) 3.
The cyclic five‐carbon sugar is different between DNA and RNA. ( ) 4.
DNA has rare mutant. This property provides genetic variability for evolutionary change. ( ) 5.
The double‐stranded helix of DNA was defined by James Watson and Francis Crick in 1953. ( ) III. Choose the Best Answer 1. The linkage among nucleotides in polynucleotide chain is ( ). A. H‐bond B. Phosphodiester bond C. Phosphoester bond D. Glycosidic bond E. Peptide bond 2. The basic unit of nucleic acids is ( ). A. Amino acid B. Nucleotide C. Protein D. DNA E. RNA 3. The phosphate of nucleotide is linked to ( ) of the sugar. A. 1’‐carbon atom B. 2’ ‐carbon atom C. 3’ ‐carbon atom D. 4’ ‐carbon atom E. 5’ ‐carbon atom 4. The phosphate of nucleotide is linked to the cyclic five‐carbon sugar by a ( ) bond. A. H‐bond B. Phosphodiester bond C. Phosphoester bond D. Glycosidic bond E. Peptide bond 5. In DNA molecule, the base A is paired with ( ). A. A B. G C. C D. T E. U 6. Which of the following is right about the function of mRNA ( )? A. As a template for protein synthesis B. As a component of ribosome C. Store the genetic information D. Transferring amino acids to ribosomes for protein syhthesis E. None 7. There are ( ) base pairs per helical turn. A. 10 B. 9 C. 8 D. 7 E. 6 8. RNA molecule has a local region of double helix. It is called ( ). A. Major groove
B. Hairpin loop C. β sheet D. Insertion/deletion loop E. Lac operon 9. The length of one helical turn is ( ). A. 0.34nm B. 3.4nm C. 34nm D. 2nm E. 0.2nm 10. Which of the following is not right about DNA or RNA ( )? A. The basic unit of DNA and RNA is nucleotide. B. Four bases in DNA are A, G, C, U. C. The structure of DNA is double‐stranded helix. D. Nucleic acids include DNA and RNA. IV. Multiple Choice 1. In RNA, four bases are ( ). A. A B. G C. C D. U 2. The three parts of nucleotides are ( ). A. Five‐carbon sugar B. Base C. Phosphate D. amino acid 3. RNA includes ( ). A. mRNA B. rRNA C. tRNA D. None 4. The function of DNA includes ( ). A. Store genetic information B. Replicate itself with high accuracy to make sure the genetic information transfer from one generation to the next C. As a template for protein synthesis D. As a component of ribosome 5. Which of the following is right about DNA and RNA ( )? A. The five‐carbon sugar in DNA is deoxyribose, and it is ribose in RNA. B. Both in DNA and RNA, there are four kinds of bases. C. There is one different base between DNA and RNA. D. The molecular structure of DNA and RNA is different. answer V. Definitions 1. Biopolymers composed of nucleotides linked in a linear sequential order through phosphodiester bonds. Two types of nucleic acids: DNA and RNA. 2. The phosphate is responsible for the connection between nucleotides in nucleic acids. The linkage among nucleotides is called Phosphodiester bond. VI. True or False 1. F 2. T 3. T 4.T 5.T VII. Choose the Best Answer 1. B 2. B 3.E 4.C 5.D 6.A 7. A 8. B 9. B 10.B VIII. Multiple Choice 1. ABCD 2. ABC 3 .ABC 4 .AB 5.ABCD