Desertification extends beyond the expansion of existing deserts to include land degradation due to human activity in drylands. Land degradation destroys or reduces the productivity of the soil, and is caused by excessive and unsustainable activities such as deforestation, overgrazing, poor land management, soil salinization, and soil erosion.
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This is an example of CONDOMINANCY.
Condominancy is said to occur when two different alleles are combined together to form a different allele, in which the alleles are expressed equally and none of them is dominant. In the example given above, the black rat population mated with the white rat population to produce offspring that are grey in colour. Thus, the white and the black colour of the parents are not dominant, but are equally expressed to give gray colour.
Hyperkalemia, depolarization
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