The present study conducted to investigate the contribution of conceptual change texts, accompanied by concept mapping instruction to eleventh-grade students' understanding of cellular respiration concepts, and their retention of this understanding. Cellular respiration concepts test was developed as a result of examination of related literature and interviews with teachers regarding their observations of students' difficulties. The test was administrated as pre-test, post-test, and delayed post-test to a total of 70 eleventh-grade students in two classes of the same high school in an urban area, taught by the same teacher. The experimental group was a class of 34 students who received conceptual change texts accompanied by concept mapping instruction. A class of 36 students comprised the control group who received traditional instruction. Besides treatment, previous understanding and logical thinking ability were other independent variables involved in this study. The results showed that logical thinking, treatment, previous understanding of cellular respiration concepts each made a statistically significant contribution to the variation in students' understanding of cellular respiration concepts. The result also showed that conceptual change texts accompanied by concept mapping instruction was significantly better than traditional instruction in retention of this understanding.