Heterozigozia

Heterozygosity refers to a genetic state in which an individual possesses two different versions, or alleles, of the same gene. This is in contrast to homozygosity, where an individual has two identical alleles for a particular gene. Alleles are different forms of a gene that arise through mutation. For example, a gene that determines eye color might have an allele for brown eyes and an allele for blue eyes. An individual who is heterozygous for eye color would have one allele for brown eyes and one allele for blue eyes.

The inheritance of alleles determines an organism's genotype, which is the specific combination of genes it carries. When an individual is heterozygous for a particular gene, their genotype is represented by two different letters, often one uppercase (representing a dominant allele) and one lowercase (representing a recessive allele). For instance, if 'B' represents the allele for brown eyes and 'b' represents the allele for blue eyes, a heterozygous individual would have the genotype Bb.

The expression of the alleles in a heterozygous individual depends on the relationship between them. If one allele is dominant over the other, the trait associated with the dominant allele will be expressed, masking the effect of the recessive allele. In the eye color example, if the allele for brown eyes (B) is dominant over the allele for blue eyes (b), a Bb individual will have brown eyes. However, if the alleles exhibit codominance, both traits will be expressed simultaneously. Recessive traits are only expressed when an individual is homozygous for the recessive allele. Heterozygosity plays a crucial role in genetic diversity within populations and influences the inheritance of traits.