Which event in meiosis increases genetic variation within a population?
A. DNA condenses to form chromosomes.

B. Segments of chromosomes cross over.
C. Chromosomes duplicate themselves.
D. Chromosomes form pairs.

Because of recombination and independent assortment in meiosis, each gamete contains a different set of DNA. This produces a unique combination of genes in the resulting zygote. Recombination or crossing over occur during prophase 1

only about ten percent of the energy at one trophic level is passed on to organisms at the next trophic level. the remainder of the energy is used in life processes or lost as heat.