Alleles

An allele is one of two or more versions of a gene that are found at the same place on a chromosome. Alleles can be dominant or recessive. Dominant alleles mask the expression of recessive alleles when they are present together. The combination of alleles present in an individual determines its genotype, which in turn influences its phenotype, or physical characteristics.

Key Points about Alleles:

1. Alleles are different versions of the same gene.
2. Alleles can be dominant or recessive.
3. The combination of alleles determines an individual's genotype and phenotype.
4. Alleles are located at the same position on homologous chromosomes.

Study Guide for Alleles:

Definition of Allele:

What is an allele and how does it relate to genes and chromosomes?

Types of Alleles:

Explain the difference between dominant and recessive alleles. Provide examples of each type.

Genotype and Phenotype:

How do alleles influence an individual's genotype and phenotype? Provide examples to illustrate this relationship.

Mendelian Inheritance:

Discuss how alleles are inherited according to Mendel's laws of segregation and independent assortment. Provide examples of each type of inheritance.

Allele Frequencies:

Explain how allele frequencies in a population can change over time through processes such as natural selection, genetic drift, and gene flow.