ANSWER KEY
Pre-Lab Questions
The Eastern Newt is the least related organism out of the three. While all three are classified into the same domain, kingdom, phylum and class the Eastern Newt is in a different order than the American Green Tree Frog and the European Fire-Bellied Toad.
DNA sequencing has allowed for the comparison of genes at the molecular level as opposed to physical traits at the organism level. Physical traits can be misleading when classifying how related two organisms are. DNA sequencing can also trace relatedness through generations and more accurately assess how closely related two organisms are.
The organism’s physical features can be used to compare it to known organisms. Some physiological features can even possibly be used to help classify it.
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Experiment 1: Dichotomous Key Practice Level American Green Tree
Fro g
European Fire-
Bellied Toadinomial Name
Table 3: Dichotomous Key Results
(2 pts each)
Post-Lab Questions
The options become more and more specific.
The dichotomous key options became more and more specific as they came closer to identifying the organism just like the classification system starts as a broad category (i.e, animal kingdom) and becomes more specific until a unique species is classified (i.e., species).
Experiment 2: Classification of Organisms
The flow chart questions will lead you to the correct classification of the organisms into their respective kingdoms. Table 2, shown above, has an error in your lab manual–sunflowers do not have motility. Most of you saw the discrepancy and went with the answer you got from the flow chart. For the blanks in the completed table (above), that’s because those answers are variable, and not necessary to identify that organism using the given flow chart. (3 pts)
Post-Lab Questions
Yes. If the questions in the “tree” were answered correctly, each organism should end up in the correct kingdom.
Your answers will vary, but you should have brainstormed other organisms that belong to each domain or kingdom. For example, fish are also in the animal kingdom – how do fish differ from bears (gills instead of lungs, live in water, etc.)? What makes types of protists different from each other (shape, form of motion, etc.)?
Answers will vary.
Example: