7.1.3 Codominance and Multiple Alleles

• Match the inheritance pattern with an example:

  Codominance ↔️ Blood type AB

  Complete dominance ↔️ Brown eyes vs blue eyes
• What is the phenotype of roan cattle in codominance?

  Speckled red and white
• In codominance, the phenotype of a heterozygote is a combination of traits from both alleles
• Codominance occurs when two different alleles of a gene are both fully expressed in the phenotype
• How do heterozygotes in codominance differ from homozygotes?

  Display distinct traits
• What feather color do BW heterozygotes exhibit in Andalusian chickens?

  Blue-gray
• Match the genetic inheritance pattern with its example:

  Multiple Alleles ↔️ Human Blood Types (A, B, O)

  Codominance ↔️ AB Blood Type
• What is the definition of codominance in genetics?

  Both alleles are fully expressed
• How do heterozygotes differ in codominance compared to complete dominance?

  Distinct traits from homozygotes
• Blue-gray feathers in Andalusian chickens are an example of codominance.


  True
• In human blood types, which antigen is expressed in codominance for type AB blood?

  Both A and B
• In codominance, what happens to allele expression?

  Both alleles are fully expressed
• In humans, blood type AB is an example of codominance
• Multiple alleles refer to the presence of more than two alleles for a particular gene
• In human blood types, which allele is recessive?

  O
• Arrange the alleles of the C gene in rabbits according to their dominance hierarchy:

  1️⃣ C (full color)

  2️⃣ c^h (Himalayan)

  3️⃣ c^e (chinchilla)

  4️⃣ c (albino)
• In codominance, there are only two alleles for a gene, while in multiple alleles, there are more than two in the population
• An example of codominance is blood type AB, while an example of complete dominance is brown versus blue eyes
• AB blood type in humans is an example of codominance.


  True
• Match the examples of codominance with their descriptions:

  AB blood type ↔️ Expresses both A and B antigens

  Roan cattle ↔️ Mix of red and white hairs

  Andalusian chickens ↔️ Blue-gray feathers from black and white alleles
• Arrange the rabbit coat color alleles from most dominant to least dominant:

  1️⃣ C (full color)

  2️⃣ c^h (Himalayan)

  3️⃣ c^e (chinchilla)

  4️⃣ c (albino)
• Match the inheritance patterns with their examples:

  Codominance ↔️ AB blood type

  Multiple alleles ↔️ ABO blood group in humans
• In codominance, heterozygotes display traits intermediate between the two alleles.


  True
• Individuals with blood type AB express both A and B antigens
• What is the key difference between codominance and complete dominance?

  Allele expression
• Order the steps involved in analyzing codominance in inheritance:

  1️⃣ Define the genetic inheritance pattern

  2️⃣ Identify the heterozygous genotype

  3️⃣ Express both allele traits in the phenotype
• In codominance, the heterozygous phenotype combines traits from both alleles

  True
• Roan cattle exhibit codominance with red and white hair colors.

  True
• Multiple alleles are present in the population but individuals can only carry two alleles at a time.


  True
• The ABO blood group in humans is determined by three alleles: A, B, and O
• What are the four possible blood types in the ABO system?

  A, B, AB, O
• What is the key difference between codominance and multiple alleles in terms of allele expression?

  Codominance expresses both alleles fully
• What is codominance in genetics?

  Both alleles are expressed
• What is the phenotype of heterozygous offspring in codominance?

  Combination of both alleles
• What is the definition of multiple alleles?

  More than two alleles
• In human blood types, which alleles are codominant?

  A and B
• What is the significance of codominance in inheritance?

  Greater diversity of phenotypes
• In rabbits, the C gene controls coat color with four alleles.


  True
• Codominance and multiple alleles are both genetic inheritance patterns.


  True
• Codominance is a genetic inheritance pattern where two different alleles are both fully expressed in the phenotype.


  True