Venn Diagram Comparison of Frog and Human Skeletons

Themes:

• Skeletal System: Structure and Function
• Comparative Anatomy: Frogs and Humans

In the space below, you will create a Venn diagram. A Venn diagram is a graphical way of comparing and contrasting two things.

• Draw two large circles side by side which overlap in the middle of the paper (so it looks like a very large Master Card symbol).
• Above the left circle, write "Frog Skeleton." Above the right circle, write "Human Skeleton."
• Fill in the diagram by describing features or characteristics that only the frog skeleton has (like a very large mouth, four fingers in the hands) in the left circle and ones that only the human skeleton has (like 12 pairs of ribs, a relatively small mouth) in the right circle. Consult the bones hut on Frog Island and other resources to help you fill out the different areas of the Venn diagram.
• In the overlap section, describe features or characteristics that both skeletons share (like phalanges, metacapals, and carpals in the hand)
• After you complete your diagram, answer the questions.

Answer the following questions:

1. Why do you think frogs have a larger mouth (compared to the rest of their body) than humans do?

2. Thinking about how they use them, why do you think the shape of a frog's foot and legs is different from a human's?

3. If you look carefully at the frog's hand, you can see a tiny metacarpal that is all that is left of their first finger (the thumb). Why do you think humans didn't slowly lose that finger over hundreds of generations as well?

4. Why do you think the overall shape of the arms of both frogs and humans is similar?

5. In frogs, the forament magnum (the hole in the skull that the spinal cord passes through) is located in the back of the skull. Where do you think it is in humans and why?

6. What is the big difference between the tarsal bones of a frog and of a human?

7. Humans have two bones in their forearm that can rotate around each other. How is it different in frogs, and why do you think it is different (hint: think about how each uses their forearms)?

8. The cranium is the part of the skull that surrounds and protects the brain. Compare the size of the cranium in the frog and in the human. Why do you think this is different?

9. Imagine you were some alien scientist in the future who was exploring the Earth after some catastrophe wiped out all life. If you were looking at the skeletons of a human, frog, and fish, and the shell of a lobster, which would you think are most closely related and which are most distantly related and why?