Answer:
An ecosystem is a community of living organisms with nonliving components of their environment, interacting together as a system
Explanation:
I vivid description of an ecosystem is that species of different kinds make up populations which makes up communities.
The most likely answer here is 1 and 4.
1) closed circulation
2) The spleen can easily be damaged if someone suffers a sever injury to the stomach. When the spleen is damaged, it can cause pain in the abdomen, dizziness, and pain in the left shoulder.