Final answer:
The phenotype of a cell is determined by gene expression, influenced by an organism's genotype and environmental conditions. Alleles, which are different versions of a gene, contribute to phenotypic variation, and a myriad of genetic and environmental factors influence phenotype distribution in a population.
Step-by-step explanation:
The phenotype of a cell is ultimately determined by the genes that are expressed under specific environmental conditions. While many cells could share the same genotype, or the Genetic makeup, their phenotypes can vary widely due to differences in gene expression. Phenotypic variation is also contributed by alleles, which are different versions of a gene. In cases where an allele only affects the phenotype when an individual has two copies of that allele, it is known as a recessive allele. Conversely, a dominant allele can affect the phenotype when only one copy is present.
Genetic drift, the bottleneck effect, and the founder effect can influence allele frequencies in a population and thus contribute to phenotypic diversity. These factors along with gene flow, mutation, non-random mating, and environmental variance are all influential in how phenotypes are distributed within a population. It's important to understand that most complex phenotypes, like those in humans and other organisms, do not result from a single gene but from the interaction of multiple genes and environmental factors.
Mendel's laws and the understanding of alleles, genotype, and phenotype are fundamental in explaining how characteristics are inherited and how they can manifest in different observable traits. While a particular phenotype can result from various genotypes, it is the combination of an organism's genotype and its environment that produces the phenotype.