Guard cells are specialized cells in the epidermis of leaves, stems and other organs that are used to control gas exchange,
including water vapor via transpiration. Guard cells perceive and process environmental stimuli to trigger cellular responses
resulting in stomatal opening or closure. All but one environmental stimuli might trigger stomatal opening. That would be

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)

the sun's light combined with the visible wavelenghts form what is called ultraviolet radiation, which are the long waves at the end of a visible light sprectrum.

hope it ,

bioteacher101