Download CS4030: Tutorial 1- Biological Issues (from Bioinformatics ch 1)

CS4030: Tutorial 1- Biological Issues (from Bioinformatics ch 1)
1. Deoxyribonucleic acid (DNA) differs from ribonucleic acid (RNA) in two ways: (1) RNA uses
the nitrogenous base uracil in place of DNA’s thymine, and (2) the hydroxyl (OH) group
attached to the 2’ carbon of the deoxyribose sugar of RNA is replaced with just a hydrogen
(H) in DNA. Sketch the chemical structure of the deoxyribose sugar used by DNA in the
ribose sugar used in RNA.
2. Diagram the ”Central Dogma” of molecular biology complete with labels that indicate the
portions that correspond to transcription and translation and indicate what enzymes are
responsible for those important steps.
3. Examine the chemical structures of the amino acid R groups shown in figure 1.5b of chapter
1 of Bioinformatics (which you should by now have obtained electronically). What atom(s)
is/are found in the R groups that are in the hydrophilic amino acids that generally is absent
in the nonpolar group?
4. How many nucleotides long would a DNA sequence need to be in order for it not to be found
by chance more than once in a genome whose size is 3 billion base pairs long?
5. What sequence of amino acids would the following RNA sequence code for if it were to be
translated by a ribosome?: 5’-AUG GGA UGU CGC CGA AAC -3’. What sequence of amino
acids would it code for if the first nucleotide were deleted and another ”A” were added to the
3’ end of the RNA sequence?
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