CPSC 445/545 - Assignment 1 (covers Module 1)

handed out Thu, 04/09/23; due Thu, 04/09/30


1 DNA, RNA, Proteins [5 marks]

Consider the following (incomplete) eukaryotic mRNA sequence:

5'-AAAUGUGUGUCCGUCUGACU...CCUUCUCAGGGCGCAUAAUC-3'

(a) What is the corresponding complementary DNA sequence? [1 mark]

(b) What is the amino-acid sequence of the corresponding gene product (protein), under the assumption that translation starts at the beginning of the mRNA? [2 marks]

(c) What can you say about the structure of the genomic DNA sequence from which this (mature) mRNA was transcribed? How would you answer the same question if the mRNA were prokaryotic? [2 marks]

(Hint: Think about all steps in the process of protein synthesis from genomic DNA in eukaryotes and prokaryotes: transcription, ...)


2 Genetic Code [7 marks]

As a reading assignment, you have read Douglas Hofstadter's article 'The Genetic Code - Arbitrary'.

(a) Briefly outline the thought experiment which is provided to support the hypothesis that the genetic code is arbitrary. (No more than 200 words.) [2 marks]

(b) Briefly outline the major objections to the hypothesis that the genetic code is arbitrary, as discussed in the article itself, including the postscriptum. (No more than 200 words.) [2 marks]

(c) Based on what you've learned so far, can you elaborate the objections from part b, lending them even more credibility? Can you think of additional objections to Hofstadter's hypothesis that are not mentioned in the article? (No more than 200 words.) [3 marks]


3 Terms and concepts [6 marks]

Provide brief explanations (at most 50 words each) in the style of short dictionary entries for the following terms and concepts:

(a) PCR [1 mark]

(b) Restriction endonuclease [1 mark]

(c) enzyme [1 mark]

(d) DNA microarrays [1 mark]

(e) snoRNA [2 marks]

Give all explanations in your own words Specify the sources of information (books, papers, webpages, etc.) you consulted for your answers.

Example:

dNTP: Deoxiribonucleoside Triphosphate {dATP, dCTP, dGTP, dTTP} [1]; also called nucleotides, dNTPs are the basic components of DNA strands. They are the building blocks required to make copies of a DNA strand [3] and are used in PCR, DNA labeling, and DNA sequencing [2].

[1] Mouse Genome Information Glossary, http://www.informatics.jax.org/mgihome/other/glossary.shtml#d
[2] BioCarta Company, http://www.biocarta.com/TDS/ntp-10001.pdf
[3] University of Washington Genome Center, "Sequencing Tutorial", http://www.genome.washington.edu/UWGC/tutorial/SequencingPCR.cfm


General remarks: