3.2. English and Turkish Students’ Alternative Conceptions
about Genetics Concepts. From the analysis of students’
responses to the TGCT items, several alternative conceptions
were identified that were held by at least 10% of the students.
A value of 10%was chosen because a higherminimum value
could possibly eliminate any valid alternative conceptions
that may have been held by significant numbers of students
[29]. English and Turkish students’ levels of selecting statements
based on known alternative conceptions are displayed
in Table 3. Sixteen significant alternative conceptions were
identified (reaching the 10% threshold in one or both of the
samples) and grouped under the headings of gene, chromosome,
relationships among gene, chromosome andDNA, and
relationships between cell divisions and inheritance. Of these
16 alternative conceptions, eight reached the 10% threshold
in both samples and the other eight only in one of the two
samples.