MISSION 3 — Frog Legs and Fish Eggs
When scientists compare DNA, there are usually thousands upon thousands—or even millions—of nucleotide bases involved. A computer then scans the sequences and aligns them in the way that provides the best match. In some cases, the computer will add “blank” spaces to improve alignment. Such spaces represent nucleotides that were added or deleted as opposed to changed in one or more lineages.
In this level, you’ll get the hang of analyzing DNA by looking at a tiny 4-base snippet. A dash (–) represents either a blank space added to improve alignment or a position that is not important for the analysis you’ve been asked to do. To make things easier, the information from the species compare tab is shown below. However, don’t forget to read the species tabs—they might help you.
Play "Frog legs and fish eggs" and answer questions 6–7 after you've completed the level.
6. Draw your completed tree from this level of the game and an equivalent tree using the "Visualize It" tool below.
You must be signed in to save work in this lesson. Log in
7. True or false: “The change from a T to a C at position 3 caused all of the changes that exist between the cichlid and coelacanth/frog.” Explain your answer.
You must be signed in to save work in this lesson. Log in