Example of natural active immunity is fighting off cold and artifical active immunity is building up a resistance to a disease due to immunization and allergic reaction is an response to antigen resulting from active immunity
This would cause the overpopulation in the grassland preserve. There would be too many antelopes and zebras that they would have to compete for survival. The food resources would run out for both species and cause a competition among every animal.
If you cut a starfish radially (cut passing through the centre of the body) in five parts, every part will regrow into a new fully developed star fish.
