Answer the following question given this paragraph: 

Reptiles have a circulatory system with a heart that pumps blood. Reptiles also have a centralized nervous system with a brain. Their brain is relatively small, but the parts of the brain that control the senses and learning are larger than in amphibians. Reptiles have good senses of sight and smell. They use their tongue to smell scents. That’s what the blue-tongued lizard in Figure below is doing. Some reptiles also have a heat-sensing organ that helps them locate the warm bodies of prey animals such as birds and small mammals.


Q: Instead of using their nose, reptiles can use what organ to smell scents?


A:
tongue