Answer:
A gene is a stretch of DNA or RNA that determines a certain trait. Genes mutate and can take two or more alternative forms; an allele is one of these forms of a gene. For example, the gene for eye color has several variations (alleles) such as an allele for blue eye color or an allele for brown eyes.
Explanation:
<span>The answer would be: a) Frost-wedging happens when water freezes and breaks rocks.
Normally, the volume of a substance will become lower when the temperature drops but when water becomes ice it will expand. Water that freezes into ice can produce a high pressure from the expansion of their volume. If enough water fills a joint in a rock, the rock might get enough force to fractured or break. This will happens in the area that has a freeze-thaw cycle like in the polar climate.</span>
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