Physical exchange between homologous chromosomes (crossover) occurs during metaphase I of meiosis. true false

False

Explanation:

Crossing over is a phenomenon unique only to the process of meiosis. It is the process whereby a segment of genetic material is exchanged between the non-sister chromatids of homologous chromosome (similar but non-identical chromosomes from both parent).

Crossing over occurs when homologous pairs lie side by side to form a structure called TETRAD in the PROPHASE I stage of meiosis. Hence, according to this question, it is FALSE as crossing over does not occur in the metaphase stage.

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.