Answer:
In an eco-system, all animals and insects are important. Since there is no picture, I'll descibe what would happen. If a keystone species went missing or extinct, shortly after the rest of the ecosystem will callapse. The bird population would decrease because lack of food, shelter or environment, then those who feed on birds will slowly decline, then worms or insects that the bird was keeping in check, overpopulate. This can have disaterous consequences, not only for this specific ecosystem but for any.
the immune system is the body system that fights infection's my friend
ANSWER:
The answer is A. swallowing
The would be under weight because the villi allows the nutrients from the food to be absorbed through the walls of the small intestine and into the bloodstream and if the nutrients can't be absorbed the person will become malnourished.
