Dredge-up properties of the non-rotating 2, 3, 5, and 7 M_⊙ models. Left panel: HRD of the four models. The blue and green circles and crosses show the beginning and end of core hydrogen and core helium burning. The red, orange, and purple plus signs show the moments of the first (2 M_⊙), second (3, 5, and 7 M_⊙), and third dredge-up episodes respectively. Right panels: surface abundances around the two dredge-up episodes that each star experiences. The initial mass of the corresponding model is indicated at the top of each subpanel.