1.5 – The origin of cells

1.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?

2. 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?

3. What is evidence for the endosymbiotic theory?

4. What is evidence for the endosymbiotic theory?

5. The statement relates to Pasteur’s experiments. What did this statement suggest?

6. What can be deduced about a striated muscle fibre from both of these statements?

7. Which of the following will contribute to the cell theory? I.     Living organisms are composed of cells. II.   All cells come from pre-existing cells by mitosis. III.  Cells are the smallest units of life.