Which waste is removed by the interactions between the respiratory and circulatory system?

I believe it’s carbon dioxide, because you use your respiratory system to breathe in oxygen, and oxygen goes through your circulatory system. And you breathe out CO2.

Think it's rice because in many countries rice is the main food so it can be traditionally served all at once.

As long as it was one lick and the dog is a bigger dog, it should be fine. watch it carefully for a few days.