Perch dissection

Pre-Lab:

Students will be responsible for answering the following pre-lab questions:

1) Describe an open circulatory system. What organisms have open circulatory systems?

2) Describe a closed circulatory system. What organisms have closed circulatory systems?

3) What is the purpose of the Perch Dissection Activity?

4) Draw and label the external anatomy of the perch.

5) Label the internal anatomy of the perch on the diagram provided.

6) Outline the dissection procedure to examine the internal anatomy of the perch.

At the beginning of class, the teacher will collect the pre-lab questions. Anyone who has not completed them will be asked to do so at that time.

At the end of the period, students will not be dismissed until all the garbage has been thrown out, the apparatus washed, dried and placed where it was found and all the lab benches are clean.

The students will be expected to hand in a lab write-up (excluding a hypothesis), their perch diagram and answers to the discussion questions.

Post-Lab Discussion Questions:

1. What evidence is there of a rich blood supply in the gills? Why is this rich blood supply important?

2. Is the perchs circulatory system open or closed? Support your answer by describing what you observed.

3. What evidence is there that the perchs circulatory system is linked to the systems for digestion and gas exchange?

4. What systems did you observe in the perch that help maintain the perchs internal environment?

5. If a perch had a damaged swim bladder that could hold no air, would the fish sink to the bottom or float? Explain.