Neurons Just as it moves rapidly from the lungs into the bloodstream, nicotine (shown here as green chevrons) also easily diffuses through capillary walls. It then migrates to the spaces surrounding neurons—gangly cells that transmit nerve impulses throughout the nervous system. These impulses are the basis of our thoughts, feelings, and moods. Previous | Next Resources | Teacher's Guide | Transcript | Site Map | Search for a Safe Cigarette Home Search | Site Map | Previously Featured | Schedule | Feedback | Teachers | Shop Join Us/E-Mail | About NOVA | Editor's Picks | Watch NOVAs online | To print PBS Online | NOVA Online | WGBH © | Updated October 2001 |