Science is at heart a rational activity. Reasoning, being an important component of critical thinking has been successfully taught using Socratic methods. As an approach, the instructor or designer of instruction models an inquiring and probing mind focusing on providing questions and not answers. The main aim has been to allow learners to construct and evaluate their own reasoning or judgements explicitly, thereby making it consistent with current constructivist approaches to teaching and learning. Mendelian genetics has long been identified as an important subject but it is perceived as difficult because it requires students to operate at a higher level of scientific reasoning as well as to have mastery of theoretical genetic concepts. Success in concept acquisition and problem solving depends on many variables. Higher order questions were formulated and integrated into the instructional module for instruction on Mendel's first and second laws. This form of cognitive scaffolding was embedded in the learning cycle model of instruction. This paper discusses a study done on 262 students undergoing a matriculation programme of the Ministry of Education, Malaysia looking into the elements of higher order questions and their benefits on their performance on problem solving in Mendelian genetics at the preuniversity level. (Contains 3 tables.)