Josh McDermott lectures on smell and taste as part of MIT's 9.35 Perception course. He covers how olfactory receptors in the nose detect airborne chemical compounds and how taste receptors on the tongue register basic taste qualities, explaining the transduction process that converts chemical signals into neural activity. The lecture addresses how these two chemical senses interact to produce flavor perception, and how the receptor systems differ from vision and hearing in terms of coding and specificity. Drawing on findings from sensory neuroscience, McDermott walks through the anatomy of the relevant receptor cells and the pathways carrying their signals to the brain. This is lecture 23 in the Spring 2024 offering of the course, continuing the term's survey of perceptual systems with a focus on the chemical senses rather than the more commonly studied visual or auditory modalities.