The actual answer (sorry for the late reply, but this is for the rest of the people coming afterwards) would actually be B) Switch primitive reptile with primitive insect. Insects came before any reptiles.
Introducing a predator means there will be less prey which will help balance the population of prey. Some predators may run out of food and there might be no prey left for them. If the prey were removed the predator population would decline.
I would say urinary system due to it containing fluid. But I also want to say endocrine so between them both
Answer:
Excessive amounts of nutrients can lead to more serious problems such as low levels of oxygen dissolved in the water. Severe algal growth blocks light that is needed for plants, such as seagrasses, to grow. When the algae and seagrass die, they decay
Explanation:
Typically it'd be called spawning or in some cases it could be called "roe".
So either "spawn" or "roe".
