Biology · Variation and Genetics
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The phenotype of heterozygote is distinct from those of the two homozygotes, not an intermediate expression, this is termed as:
- A
Dominance
- B
Complete dominance
- C
Incomplete dominance
- D
Codominance
Codominance, in genetics, is a phenomenon in which two alleles (different versions of the same gene) are expressed to an equal degree within an organism. As a result, traits associated with each allele are displayed simultaneously. Example: Human blood group AB
Dominant refers to the relationship between two versions of a gene. Individuals receive two versions of each gene, known as alleles, from each parent. If the alleles of a gene are different, one allele will be expressed; it is the dominant gene. The effect of the other allele, called recessive, is masked.
Complete dominance is when one allele is fully dominant over the other.
Incomplete dominance is when a dominant allele, or form of a gene, does not completely mask the effects of a recessive allele, and the organism's resulting physical appearance shows a blending of both alleles.
Codominance, in genetics, is a phenomenon in which two alleles (different versions of the same gene) are expressed to an equal degree within an organism. As a result, traits associated with each allele are displayed simultaneously. Example: Human blood group AB
Tagged under Biology · Variation and Genetics · 2017