Download BIOS 1700 Dr. Tanda 8 September 2016 Week 3, Session 2 1

BIOS 1700
Dr. Tanda
8 September 2016
Week 3, Session 2
1. Which amino acid has a disulfide bond? Which amino acid has the smallest R group
and free rotation? Which amino acid is stiff and kinked?
2. What protein structures are held together by hydrogen bonding?
3. What is the purpose of chaperones?
4. The large subunit in a ribosome has three binding sites for tRNAs. Name these three
binding sites.
5. Describe each level of protein structure.
Primary:
Secondary:
Tertiary:
Quaternary:
6. What is the difference between heterodimer and homodimer? What level of protein
structure do these terms pertain to?
7. Could a protein complex function if one of the subunits was missing or was not
assembled correctly?
8. Illustrate a ribosome. (Include: large subunit, small subunit, exit site, peptidyl site,
aminoacyl site)
9. Associate each level of protein structure with a picture below.
Gly
Ser
10. Avery and his colleagues wanted to understand what biological molecule(s)
transforms nonvirulent Streptococcus pneumoniae to a virulent one. So, they treated
extract of the heat-killed virulent strain with a various enzymes prior to mixing it with a
nonvirulent strain. They used RNase, protease, and lipase (lipid-digesting enzyme). Do
you think that this experiment allows you to definitively identify what biological
molecule(s) contain(s) the genetic information? State why you think so.
11. A famous biologist in Athens, OH, claimed that he created a strain of the fruit fly
(eukaryotes) that does not have any activity of one of the proteins building spliceosome.
Dr. T immediately dismissed this biologist’s claim. Explain.
12. Hypothetically, the same gene exists in E. coli (prokaryote) and in yeast (eukaryote).
The speed of transcription of any genes in E. coli and yeast is the same. Dr. T measured
accumulation of the protein from this gene in E. coli and yeast and observed that E. coli
accumulated this protein much faster than yeast. What may explain this observation?
13. Below is a double-stranded DNA segment, which is transcribed.
5’-CGTAAATGGCGCGA-3’
3’-GCATTTACCGCGCT-5’
Write a RNA sequence when the top strand is used as a template in the 5’ to 3’ direction.
14. Polymerization of RNA molecule during transcription requires energy. Where does
the energy for this reaction come?
Cys