Drag the tiles to the correct boxes to complete the pairs. Match the inheritance patterns with the scenarios that exemplify them. Codominance Multiple alleles Incomplete dominance A man with straight hair and a woman with curly hair have a child with wavy hair. → Genes with the alleles IA, IB, and i are responsible for the expression of A, B, and O blood types. → A red flower and a white flower produce an offspring with equal proportions of red and white coloration.
The Correct Answer and Explanation is:
Correct Pairs:
- Incomplete dominance → A man with straight hair and a woman with curly hair have a child with wavy hair.
- Multiple alleles → Genes with the alleles IA, IB, and i are responsible for the expression of A, B, and O blood types.
- Codominance → A red flower and a white flower produce an offspring with equal proportions of red and white coloration.
Explanation
Inheritance patterns describe how traits are passed from parents to offspring through genes. The three patterns in this case—incomplete dominance, multiple alleles, and codominance—represent different mechanisms of gene expression.
Incomplete dominance occurs when neither allele is completely dominant over the other. Instead of showing one trait exclusively, the offspring expresses a blended phenotype. For example, a man with straight hair (possibly SS) and a woman with curly hair (CC) may have a child with wavy hair (SC). The wavy hair is a result of the blending of the two different hair textures, showing that neither straight nor curly is completely dominant.
Multiple alleles refer to the existence of more than two forms of a gene in the population. A classic example is the ABO blood group system, where three alleles—IA, IB, and i—combine in various ways to produce four blood types: A (IAIA or IAi), B (IBIB or IBi), AB (IAIB), and O (ii). Although each person can only have two of these alleles, the population carries all three, and they interact to determine blood type.
Codominance occurs when both alleles in a heterozygous organism are fully and simultaneously expressed, without blending. An example is a cross between a red flower and a white flower resulting in an offspring that displays both red and white patches. This differs from incomplete dominance because both traits appear distinctly, not as a mix.
Understanding these patterns helps in studying heredity, predicting genetic outcomes, and grasping the complexity of trait inheritance beyond simple dominant-recessive relationships.
