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.
Answer:
calcium, iron, magnesium, potassium, chloride, zinc, sodium, sulfur
Explanation:
The warmer the star, the bluer it will appear. The cooler a star, the more red it will appear.
Proxima Centauri Red Dwarf Stars for example have significantly less heat, therefore their red color.