<span>One can infer from this situation the following things: first, the fertilizers used in the farm eventually get to the adjacent river. Second, these fertilizers may be providing some benefitial conditions to the algae, allowing it to grow exponentially and strongly.</span>
The excretory system allows animals to remove metabolic waste their bodies. Many of these substances are potentially toxic. in Mammals nitrogenous toxins like urea are expelled through liquid urine while in reptiles and birds the nitrogenous compounds are expelled as a solid. This allows birds and reptiles to use less water in the processes of metabolism.
The answer is the first one