| 1. How did the Platyhekmithes advace over the coelenterates? (read both your new and old text) 2. Check your text or handout on the nephridium of the earthworm. What is the pathway of urine in a nephridium? Draw a Nephridium and label it. Then write the parts in order of flow as numbered steps. Show how wastes are picked up from one segment but drain out of the next segment. |
This side is for writing basic points as as planner. |
| 3. Why do you suppose there are loops in the main
Nephridium?
4. Why did an extensive capillary network evolve around the loops of the nephridium (explain carefully) 5. Study a human Nephron in your textbook. Then explain how the Nephron is similar in structure and function to the Nephridium! Also indicate differences. | f |
| 6. Explain how terrestrial Arthropod Malpighian tubule excretion works (old book pg 502, new book pg 611) Also check the picture on pg 611 of the grasshopper. Use Steps. Draw a grasshopper's abdomen with the Malpighian tubules. Place arrows on your diagram to show flow of liquid waste. (You can do this if you read page 612 carefully). | f |
| 7. WHY is excretion necessary for both humans and
earthworms?
8. What is the main nitrogenous chemical in human urine? (earthworms excrete a lot of ammonia along with urea but this is okay because urine is dilute). | f |
| 9. WHY does mammalian urine need to be concentrated but it is fine if earthworm urine is dilute? | f |
| 10. Draw a diagram of three segments of an earthworm from a top view, showing two nephridia per segment. Be sure to label the septa and all parts of one of the six nephridia. | f |
