What are alleles and where are they found?

An allele is an alternative form of a gene (in diploids, one member of a pair) that is located at a specific position on a specific chromosome. Diploid organisms, for example, humans, have paired homologous chromosomes in their somatic cells, and these contain two copies of each gene.

Explanation:

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.

some of your causes might be acidic rain or natural wildfires that cause the parks to be degraded

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