compare digestion and respiration.
how would unhealthy teeth or germs affect digestion.
how are the digestive and circulatry system alike.
explain how the heart and lung help each other provide oxtgen to the body.
how would unhealthy teeth or germs affect digestion.
how are the digestive and circulatry system alike.
explain how the heart and lung help each other provide oxtgen to the body.