2.4 – Proteins

1.Which molecule could be hydrolysed into amino acids?

2. Which of the molecules contain peptide bonds or are sugar molecules?

3. How does the proteome of a species contain a larger number of proteins than genes that code for these proteins?

4. Cladograms can be created by comparing DNA or protein sequences. The cladogram on the left is based on DNA sequences and the cladogram on the right is based on comparing protein sequences. What is the reason that cladograms based on DNA sequences are more reliable predictors of the phylogenetic relationship of species than cladograms based on protein sequences?

5. The most abundant structural protein in the human body is found in ligaments and skin. What is the name of this protein?

6. The bacterium Neisseria gonorrhoeae causes infections related to the human reproductive system. The graph shows the percentage of samples in which this bacterium showed resistance to six antibiotics over a period of ten years. What is a possible explanation for the total percentage resistance being larger than 100% in 2010?

7. The diagram shows a molecular structure. Which type of molecule is shown?

8.Which is an effect of protein denaturation?

9. What are these molecules?

10. The image shows the structural formula of a molecule. What is this molecule?

11. Where are proteins synthesized by free ribosomes used?  

12. A channel protein is used to transport ions across a membrane. What would you expect to find lining the inside of the channel?

13. Which molecular structure correctly illustrates two amino acids linked by a peptide bond?

14. How many molecules of water are required to completely hydrolyse a polypeptide made up of 23 amino acids?  

15. Which type of molecule is shown in the diagram below?

16. Which substance in prokaryotes contains sulfur?

17. What is a role of sulfur in living organisms?