How does crossing-over result in genetic recombination? A. It reduces the original cell’s chromosome number by half.

B. It mixes half the maternal chromosomes with half the paternal chromosomes.

C. It randomly separates the maternal and paternal chromosomes.

D. It permits the exchange of genetic material between homologous chromosomes.

satellites are frequently used to make observations of the orbit on earth

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.

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