Table 2.

Features of the physical models of meiosis that student groups created^a

Group	Meaning of size	Meaning of color	Chromosome structure	Pairing during meiosis I	Crossing over	Overall model
1	No differences	Parental origin	Hybrid, unreplicated	None (sister chromatids only)	Not shown	Poor
2	Homologous pairs	Homologous pairs	Correct	Homologous pairs	Not shown	Moderate
3	Homologous pairs	Homologous pairs	Correct	Mispaired	Not shown	Moderate
4	Homologous pairs	Homologous pairs	Correct	Homologous pairs	Different alleles represented	Good
5	Homologous pairs	No differences	Correct	Homologous pairs, oriented incorrectly	Not shown	Moderate
6	No differences	Parental originb	Correct	Homologous pairs	Different alleles represented	Good
7	No differences	Homologous pairs	Correct	Homologous pairs	Not shown	Moderate
8	No differences	Homologous pairs	Correct	Homologous pairs	Not shown	Moderate
9	No differences	Homologous pairs	Correct	Homologous pairs	Switching of segments represented	Moderate
10	Homologous pairs	Homologous pairs	Correct	Homologous pairs	Not shown	Moderate
11	Homologous pairs	Homologous pairs	Correct	Homologous pairs	Not shown	Moderate
12	Homologous pairs	Parental origin	Hybrid, replicated	Nonspecific	Not shown	Poor
13	No differences	Homologous pairs	Correct	Homologous pairs	Not shown	Moderate
14	Homologous pairsc	Parental origin	Correct	Homologous pairs	Switching of segments represented	Good
15	No differences	Homologous pairs	Correct	Homologous pairs	Not shown	Moderate

^aShaded boxes indicate places in which student models deviated from the classic representations used in most textbooks.

^bThis group used the same color for the chromosome arms for pairs of homologues but different-colored centromeres to represent origin.

^cThis group showed only two pairs instead of three pairs.