LIFS1901 2022 Spring 4 (Determination of Form and Function of an Organism)

Review Question Set

Multiple-Choice Questions

Choose the best answer for each question

1.    The process of protein synthesis using RNA as the template is known as _____.

A. central dogma

B. translation

C. genetic code

D. gene expression

E. transcription

2.    Which is true?

A. rRNAs contain codons, but mRNAs and tRNAs do not.

B. mRNAs contain codons, but rRNAs and tRNAs do not.

C. mRNAs, rRNAs and tRNAs contain codons.

D. tRNAs contain codons, but mRNAs and rRNAs do not.

E. mRNAs, rRNAs and tRNAs do not contain codons.

3.    Which is true about the organization of a protein-coding gene in the simplest form?

A. Its protein-coding region is downstream of its regulatory region.

B. Its protein-coding region is in the middle of its regulatory regions.

C. Its protein-coding regions and regulatory regions are interspersed with each other.

D. Its regulatory region is in the middle of its protein-coding regions.

E. Its protein-coding region is upstream of its regulatory region.

4.     In E. coli, lactose regulates the expression of the gene coding for the lactose- degrading enzyme by _____.

A. binding to the promoter of the gene

B. binding to the enzyme

C. binding to the ribosome-binding site of the gene

D. binding to a specific repressor protein

E. doing something other than those mentioned in the other choices

5.    Which is true about transcription of a protein-coding gene?

A. The coding strand of DNA is used as a template.

B. The RNA produced has the sequence of non-coding strand of DNA except that the T’s are replaced by U’s.

C. RNA polymerase travels from the 3’ end to the 5’ end of the template strand of DNA.

D. New ribonucleotides are added to the 5’ end of the growing RNA.

E. None of the above

6.    In which way does DNA serve as the ultimate determinant form and function of an organism?

A.   It acts as enzymes catalyzing reactions of the organism.

B.   It determines what proteins are produced by the organism.

C.   It acts as structural components that build the organism.

D.   It stores the energy required for all the activities of the organism.

E.   None of the above

7.     Which is NOT a process involved in regulation of expression of a protein-coding gene?

A.   Synthesis of RNA

B.   Synthesis of protein

C.   Degradation of protein

D.   Structural modification of protein

E.   None of the above

8.     The differences between different types of bodily/somatic cells in a multicellular organism are caused by ______ in these cells.

A.   different genes

B.   different DNA sequences

C.   different amounts of DNA

D.   different genes being expressed

E.   none of the above

9.     When a less specialized cell differentiates into a more specialized cell, ______ in the cell changes.

A.   the gene expression pattern

B.   the amount of DNA

C.   the sequence of DNA

D.   the number of chromosomes

E.   none of the above

10.   If an organism has about 10000 genes in total, it should have approximately ______ protein-coding gene(s).

A.   10000

B.   1000

C.   100

D.   10

E.    1

Multiple-True/False Questions

For each question, there can be 0 to 4 true branches. Determine the validity of each of the 4 branches.

11.  ______ is a normal base pair in nucleic acid.

A. A-T

B. A-G

C. A-U

D. C-G

12.  ______ is DIRECTLY involved in polypeptide synthesis process.

A. DNA

B. mRNA

C. rRNA

D. tRNA

13.  ______ is one of the functions of regulatory regions of a protein-coding gene.

A. Controlling the rate of translation

B. Controlling the rate of transcription

C. Controlling the location at which transcription starts

D. Controlling the amino acid sequence of the protein

14.  RNA splicing ______

A.   deletes portions of DNA from a gene.

B.   deletes portions of RNA from the original product of transcription.

C.   enables the production of different proteins from one gene.

D.   enables the production of the same protein from different genes.

15.  ______ has an effect on the expression level of a protein-coding gene.

A.   Translation rate of the mRNA of the gene

B.   Degradation rate of the mRNA of the gene

C.   Transcription rate of the gene

D.   Extent of modification of the polypeptide encoded by the gene

16.  ______ of a cell is generally kept unchanged throughout the lifetime of a cell.

A.   Proteins

B.   Carbohydrates

C.   Lipids

D.   RNAs

17.  A stem cell ______

A.   is a fully differentiated cell.

B.   can divide to form another stem cell.

C.   can divide to form a more specialized cell.

D.   can be naturally generated by a more specialized cell.

18.  In general, ______

A.   a eukaryotic cell has more DNA than a prokaryotic cell.

B.   a eukaryotic cell has more genes than a prokaryotic cell.

C.   a eukaryotic cell has more chromosomes than a prokaryotic cell.

D.   the proportion of protein-coding DNA in a eukaryotic cell is higher than that the proportion of protein-coding DNA in a prokaryotic cell.

19.  ______ is involved in either initiation, elongation or termination of transcription.

A.   Formation of basepairs between deoxyribonucleotides and ribonucleotides

B.   Formation of basepairs between ribonucleotides

C.   Breaking of basepairs between deoxyribonucleotides

D.   Breaking of basepairs between deoxyribonucleotides and ribonucleotides

20.  ______ is involved in either initiation, elongation or termination of translation.

A.   Formation of basepairs between deoxyribonucleotides

B.   Formation of basepairs between deoxyribonucleotides and ribonucleotides

C.   Formation of basepairs between ribonucleotides

D.   Breaking of basepairs between ribonucleotides

Short-Answer Questions (each worth 2/3% of course assessment)

Given below is the base sequence of a DNA strand. Make use of the genetic code table to answer Questions 21 to 24 about this DNA strand.

5’---ATATGAACCGTACTCCGGTATCATACGGCGACTGACTGTTAGCG---3’

21.  Write the base sequence of the DNA strand that forms double-stranded DNA with the given DNA strand.

22.  If the given DNA strand is the coding strand for a protein, write the sequence of the mRNA formed by the transcription of this DNA strand.

23.  If the start codon is present in the given DNA strand, write the amino acid sequence of the polypeptide encoded by this DNA strand.

24.  What is the sequence of the anticodon of the tRNA that carries the second amino acid of the polypeptide encoded by this DNA strand?