HELP PLEASE! Fill in the blanks

1) __ species - affect the type and abundance of other species in an ecosystem. the ecosystem would be drastically different if keystone species. Disappeared as they regulate the populations of other species.

2) __ species - also known as the _____ ____ ____, this species is one whose presence or absence indicates the quality or characteristics of certain environmental conditions. ____
Are good indicator species because they are very sensitive too changes in environmental conditions, especially when pathogens like __
Or fungi are present In the environment.