Answer: a. the lowest trophic level
Explanation:
The keystone species is the one on which the entire ecosystem depends upon. It maintains a balance in the ecosystem. If this species is removed the ecosystem will drastically change. The members of the keystone species are abundantly available at the lowest trophic level. This will help in making a balance in a community or ecosystem. If some members die others will be available to survive others.
Gas exchange because each stoma in the leaf can be opened or closed. In the light the guard cells aboard water and become turgid and the stoma opens
Answer:
the sun or grass
Explanation:
first the sun because the sun helps produce photosynthesis which grows the grass so that other animals can eat from the grass
