Shells are considered biotic because they come from living things. Biotic describes something living or use to be living such as plants and animals. So shells are considered biotic because they come from a living organism.
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What does this question even mean
Both parents must be carriers, which means they have the heterozygous gene (one uppercase letter & one lower case letter). They will still carry that mutated gene (because they have a lower case letter), and their offspring will have a 25% chance of getting a recessive disorder. The percentage is low but still possible.
Genetic drift is such type of mutation that may become more common in the population and over time due to the process
Genetic drift is describes as the random fluctuations in the numbers of the gene variants in a population. Genetic drift may takes place when the occurrence of the variant forms of the gene, called as alleles, increases and also decreases by chance over time. These variations is the presence of alleles are to be measured as the changes in allele frequencies. In the population, the different of alleles that create the coat color are equally distributed. for example A disease which comes into the rabbit population and kills the 98 of the rabbits. The only rabbits that are is left are red and grey rabbits, simply by the chance. The genes have thus called “drifted” from 6 alleles to only 2.
To know more about Genetic drift visit:
brainly.com/question/11919163
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