Mendelian Genetics

Your grade = your score/119

 

1. Define genetics and heredity. 2 points

2. What was Gregor Mendel’s contribution to Science? 2 points

3. What were the advantages of using the pea plant for Genetic research? 6 points

4. What were the 7 traits that Mendel selected for further study? 7 points

5. Mendel’s experiments had three features that represented improvements over previous experiments involving genetic crosses. What were they? 6 points

6. Explain the technique that Mendel used to perform a monohybrid genetic cross using the flower of a pea plant that had yellow seeds with the flower of a pea plant that had green seeds. What were the offspring from such a cross called? 4 points

7. Explain the terms dominant and recessive. 4 points

8. Explain the terms phenotype and genotype. 4 points

9. Define the terms gene, allele. 4 points

10. Define the terms homozygous, heterozygous. 4 points

11. State Mendel’s Law of Segregation. 2 points

12. Perform a genetic cross of pea plants with purple flowers with pea plants with white flowers. Use W for the purple trait, and w for the white trait. Show the results for the F1 and F2 generation. 10 points

 

P1

 

 

F1

 

 

 

 

13. What is the phenotypic ratio for this cross? The genotypic ratio? 4 points

14. What is a test cross? 2 points

15. Perform a test cross of pea plants with purple flowers with pea plants with white flowers. Use W for the purple trait, and w for the white trait. 20 points

Using the example of a cross of pea plants with purple flowers with pea plants with white flowers, let’s assume the parent chosen from the F2 generation of plants with the yellow-seeded phenotype was homozygous (WW). The test cross would be:

 

WW X ww

 

 

 

 

 

All of the individuals resulting from the cross of an individual homozygous for purple flowers with an individual that is homozygous recessive (white-flowered) will appear ____________________. The parent with the unknown genotype was ________.

 

Now consider the cross in which a heterozygous individual is chosen by chance and used for the cross:

 

Ww X ww

 

 

 

 

 

In this case there are two ____________________ individuals and two ____________________ individuals, a ratio of 1 ____________________ to 1 ____________________. The parent with the unknown genotype was ________.

16. What is a dihybrid cross? 2 points

17. State the Principle of Independent Assortment. 2 points

18. Perform a dihybrid cross using the following example. In guinea pigs, the allele for black fur B is dominant over the allele for brown fur b. The allele for short hair S is dominant for the allele for long hair s. 20 points

P1 BBSS X bbss

 

 

F1 BbSs

 

 

 

 

What is the phenotypic ratio from this cross?

 

19. What is incomplete dominance? 2 points

20. Define the term mutation. Compare chromosomal mutations to point mutations. Define gene deletion, duplication, inversion, and translocation. 12 points

 

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