Discuss the interrelationship between sea otters, sea kelp, and sea urchins, environmental science homework help

Discuss the interrelationship between sea otters, sea kelp, and sea urchins. Be sure to include in your answer the concept of what a keystone species is and which species of the three is the Keystone species.
What is succession? A mature forest community is completely destroyed by fire. Describe the stages of succession by which this community is restored.
Discuss the difference between a native species, an introduced species, and an invasive species? What impact do introduced and invasive species have on food webs?
What role to decomposers play in the law of conservation of matter?
How does biodiversity enhance stability in an ecological community? How are humans impacting biodiversity?

Extra credit:

What biome is Southeast PA located within?

Why do doctors sometimes recommend eating yogurt when taking antibiotics?

NOTE: JUST USE The “UPLOADED Powerpoint files.”