Overhunting of an herbivore will firstly cause the decrease of that herbivore population. This decrease will affect predators that feed on that herbivore in a negative way. The plants that are in the diet of the herbivore may over populate (Does not affect plant). For example think about the zebra population in the Africa. If zebra population decreases because of overhunting, the lions, cheetahs... predators that feed on zebras will have the biggest damage as their is less food source.
You are supposed to go take a walk and observe your surroundings. The concepts taught in your class are to be used so if you give me what you learned that would help. So out of those 10 relationships of each biological surrounding you list the concept taking place and then pick 5 and write a summary on the back of the page. Hope this helps...