Who won the Nobel Prize in 2004?

Directions: Read the following passage and answer the question that follows.

In 1991, Buck and Axel were the first to identify the genes that encode the odorant (smell) receptors in the brain. Receptors can be thought of as the specialised "doors" or "entryways" into brain cells that give particular substances, like the chemicals that make up odors, access to the inner workings of olfactory brain cells. That discovery sparked a renaissance of research into the sense of smell, and Buck and Axel won the Nobel Prize for their work in 2004.