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1. Introduction to Genetics51m
2. Mendel's Laws of Inheritance3h 37m
3. Extensions to Mendelian Inheritance2h 41m
4. Genetic Mapping and Linkage2h 28m
5. Genetics of Bacteria and Viruses1h 21m
6. Chromosomal Variation1h 48m
7. DNA and Chromosome Structure56m
8. DNA Replication1h 10m
9. Mitosis and Meiosis1h 34m
10. Transcription1h 0m
11. Translation58m
12. Gene Regulation in Prokaryotes1h 19m
13. Gene Regulation in Eukaryotes44m
14. Genetic Control of Development44m
15. Genomes and Genomics1h 50m
16. Transposable Elements47m
17. Mutation, Repair, and Recombination1h 6m
18. Molecular Genetic Tools19m
- Genetic Cloning
  9m
- Methods for Analyzing DNA
  9m
19. Cancer Genetics29m
- Overview of Cancer
  21m
- Cancer Mutations
  7m
20. Quantitative Genetics1h 26m
21. Population Genetics50m
- Hardy Weinberg
  19m
- Allelic Frequency Changes
  31m
22. Evolutionary Genetics29m

3. Extensions to Mendelian Inheritance

Variations of Dominance

Genetics

3. Extensions to Mendelian Inheritance

Variations of Dominance

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Multiple Choice

The gene for dark eyes is ___ over the gene for blue eyes, which is recessive.

codominant

incompletely dominant

epistatic

dominant

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Understand the terminology: A dominant gene is one that expresses its trait even if only one copy is present, while a recessive gene requires two copies to express its trait.

Identify the traits involved: Here, the gene for dark eyes and the gene for blue eyes are being compared.

Recall the relationship between dominant and recessive alleles: If dark eyes are dominant over blue eyes, then the presence of one dark eye allele will mask the expression of the blue eye allele.

Review the options: Codominant means both alleles are expressed equally; incompletely dominant means a blend of traits; epistatic refers to one gene masking another gene at a different locus.

Conclude that since dark eyes mask blue eyes and blue eyes are recessive, the correct term to describe the relationship is 'dominant'.