Which describes the greenhouse effect? an artificial process a dangerous process a natural process a new process

Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.

The transport tubes from food came down the plant are called?

What type of plant is good for a bioassay and where can i buy it? i only have a month.