SBI3U: Exploring Modes of Inheritance. Purpose

Transcription

1 SBI3U: Exploring Modes of Inheritance Assigned: Purpose Name: Due: To master understanding of various modes of inheritance by creating original creatures with various traits that are passed on by each mode of inheritance. Parameters Create an organism that has four traits that are easy to draw. They must be drawn in colour. Each trait has to use one out of the four following modes of inheritance dominance incomplete dominance (YOU CANNOT USE COLOUR FOR THIS CHARACTERISTIC!) codominance X-linked dominance Generate allele symbols so that they follow the proper formatting for each type of inheritance. Give them a species name. The males and females must be easily and appropriately distinguished from each other. Complete Table 1 for your creature showing the mode of inheritance, the first allele and the second allele and their phenotypes for each trait. You only have to write the one allele and draw the trait that goes with it. So you won t see the heterozygous traits in this chart. That will come later. P F1 Generation On one page draw a male and female of your species. They have to be true breeders for traits except for the sex-linked one. Write their personal names above their picture. These are a family, so everyone has to have a name! Choose which parent will have the dominant traits and which one will have the recessive traits by making the dominant one, the same gender as you. For the sex-linked inherited trait, the female must be a carrier. The male can have either the dominant or recessive allele. You choose. In Table 2, show their genotypes below their picture. Make sure the genotype is a string of all their alleles. Below the P generation parents complete the four Punnett Squares of the P generation cross in Table 3 below your drawings of the parental combinations, one square for each trait. Complete Table 3a by filling in the genotypic and phenotypic ratios for the F1 generation. Use whole numbers for the genotypes and percentages for the phenotypes.

2 F1 F2 Generation Complete Table 4 for the F1 male crossing with an F1 female. Complete Table 5 Punnett squares for the F1 F2 Generation Complete Table 5a by filling in the genotypic and phenotypic ratios for the F1 generation. Use whole numbers for the genotypes and percentages for the phenotypes. Four F2 offspring will be generated by using poker chips to randomly select one out of four possible outcomes for each genotype. Complete Table 6 using this process. Complete Table 6a by filling in the actual genotypic and phenotypic ratios for the F2 generation. Use whole numbers for the genotypes and percentages for the phenotypes. When you have completed the charts, and the analysis questions that follow, cut them out and mount them attractively to make a poster. Analysis Questions 1. What did you have to ensure when designing the trait that is inherited by a) dominance? b) incomplete dominance c) codominance? 2. What makes sex-linked inheritance unique from the other three inheritance patterns used in this activity? 3. Explain why the ratios of the actual outcomes may not match the predicted ratios from the Punnett squares. Describe what you would have to do differently to get results that almost perfectly matched your Punnett square ratios if they didn t. 4. If you did a Punnett square for all for traits simultaneously, a tetrahybrid cross, how many boxes would be in that Punnett square? Show your calculations for this. 5. Explain how the Law of Independent Assortment connects to this activity. (You ll have to do a little textbook reading to learn what this is). No citation is needed for this assignment. CRITERIA LEVEL 4 LEVEL 3 LEVEL 2 LEVEL 1 < LEVEL 1 Thinking & Investigation - application of skills and (e.g. design, interpretation & analysis) - applies all or almost all of the skills and - applies most of the skills and - applies some of the skills and - applies few of the skills and - applies very little skills and Communication - use of scientific terminology, symbols, conventions accurately & effectively - expresses ideas clearly shows a high shows a considerable shows a moderate shows a limited shows a negligible

3 Table 1: Traits for The Species Dominance Incomplete Dominance Codominance Sex-Linked Inheritance

4 Table 2: P Generation P Generation Names Male Female Genotype

5 Table 3: P F1 Generation Punnett Squares Simple Dominance F1 Incomplete Dominance F1 Codominance F1 Sex-linked Inheritance F1 Table 3a: F1 Punnett Square Ratios Trait F1 Genotypic Ratio F1 Phenotypic Ratio

6 Table 4: F1 Generation F1 Generation Names Male Female Genotype

7 Table 5: F1 F2 Generation Punnett Squares Simple Dominance F2 Incomplete Dominance F2 Codominance F2 Sex-linked Inheritance F2 Table 5a: F2 Punnett Square Ratios Trait F1 Genotypic Ratio F1 Phenotypic Ratio

8 Table 6: Actual F2 Offspring F2 Generation Names Genotype F2 Generation Names Genotype Table 6a: F2 Actual Ratios Trait F1 Genotypic Ratio F1 Phenotypic Ratio

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