Grade 12 Non-Mendelian Inheritance Worksheet
Explore advanced concepts in genetics beyond simple Mendelian patterns, including incomplete dominance, codominance, multiple alleles, and polygenic inheritance.
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Grade 12 Non-Mendelian Inheritance
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Read each question carefully and provide your best answer. Show all work for Punnett square problems.
1. In snapdragons, red flowers (RR) crossed with white flowers (WW) produce pink flowers (RW). This is an example of:
Complete dominance
Codominance
Incomplete dominance
Polygenic inheritance
2. Human blood types (A, B, AB, O) are an example of:
Multiple alleles and codominance
Incomplete dominance
Sex-linked inheritance
Epistasis
3. When one gene affects multiple phenotypic traits, this is called .
4. The interaction between two or more genes to control a single phenotype, where one gene masks or modifies the expression of another, is known as .
5. Traits like human height and skin color, which are determined by the cumulative effect of many genes, exhibit inheritance.
6. A cross between a black chicken and a white chicken produces offspring with both black and white feathers (erminette). What type of inheritance pattern is this, and why?
7. Explain the difference between incomplete dominance and codominance, providing an example for each.
8. In a certain breed of cat, coat color is determined by a gene with multiple alleles: C (full color), c^b (Burmese color), and c^s (Siamese color). Full color is dominant to Burmese and Siamese, and Burmese is dominant to Siamese. A full-color cat (C c^b) is crossed with a Siamese cat (c^s c^s).
Draw a Punnett square to show the possible genotypes and phenotypes of the offspring. What are the phenotypic ratios?

9. Sex-linked traits are always expressed more frequently in females than in males.
True
False
10. Environmental factors can influence the expression of genes, leading to variations in phenotype even among individuals with the same genotype.
True
False