Lab Investigation: Grasshopper Vs

Name(s)______Date______Period______

Grasshopper & Crayfish: Lab Questions/ Data sheet

Part I: Grasshopper data

1. List the main characteristics that define the Insecta class.

2. What are the stages of incomplete metamorphosis in the grasshopper?

3. How much does the nymph differ from the adult grasshopper?

4. What is the function of the labrum?

5. How are the mandibles adapted for crushing blades of grass?

6. How are the maxillae adapted for holding and cutting food?

7. What is the function of the labium?

8. How do the palpi of the maxillae and the labium function in feeding?

9. What is the function of the gastric caecum?

10. What is the function of the malphigian tubules?

11. Describe how the grasshopper’s circulatory system works. 12. Write some notes about your overall reaction to this dissection: what interested/surprised you? What did you learn the most/best from this dissection experience, as opposed to looking at illustrations?

Part II: Crayfish data

1. How many segments are on the abdomen? _____ How many pieces make up the carapace? _____

2. Where are the large compound eyes in relation to the rostrum?

3. Description: structure of the antennules and antennae.

4. Description: mouth part movements

5. Comparison: maxillipeds, chelipeds and walking legs

6. Sex of crayfish. ______

7. What is this structure and what is it used for?

8. Description: gonads, heart, and stomach

9. Observation: intestine and muscles

10. Describe the crayfish eye. What do you notice different about this structure? 11.

Major Appendages on a Crayfish Appendage Location Function