Your teacher likes to copy. Found this at https://examples.yourdictionary.com/examples-of-keystone-species.html
Grizzly bears: As predators, bears keep down the numbers of several species, like moose and elk. They also carry and deposit seeds throughout the ecosystem. Bears that eat salmon will leave their dropping and the partially eaten remains that provide nutrients such as sulfur, nitrogen and carbon to the soil.
Plant cells are the basic unit of life in organisms of the kingdom Plantae. They are eukaryotic cells, which have a true nucleus along with specialized structures called organelles that carry out different functions.They also have a cell wall that provides structural support.
B according to my school.
