2. In this chapter, you learned that some pathogens must attach to host cells to cause disease. To accomplish this, molecules on their surface (adhesins or ligands) recognize and attach to molecules (receptors or integrins) on the surface on certain host cells.
So a chromatic note, is any note you play that is not in the scale you are playing. They are also a great way to practice, especially if you are going through the pentatonic scale. Try adding one of these outside chromatic notes to your scale, and see how it sounds above the chord you are playing over.
Each key signature has several modes in them, but all the modes of each key signature contain the exact same note pitches. What makes each mode different from the other in the same key is the pattern of tones and semi-tones, not the actual pitches themselves, as is the case with regular scales, so all modes use the same notes in any given key.