Why is it important polar bears stay around

In the Arctic marine ecosystem, polar bears play a vital role. With polar bears gone, the ecosystem will be affected negatively and have a bad influence on other organisms.

1. a host loses nutrients to a parasite

2. a parasite only benefits when the host is alive (cause if the host dies the parasite dies with it )

3. producers to consumers

4. the tapeworm is a parasite

5. they convert energy from the sun (photosynthesis)

6. sunflower-robin (i think im 80% sure)

7. producer

8. consumer

9. prey

10. fresh water snails ( cause the green algea is the producer and the snails are the primary consumers and the small fish consumer so is the big fish)

x would be the most and the least would be y because there are more fruit   and seeds than flock z has insects