Tribble Genotypes and Phenotypes

Transcription

1 Name(s): Period: Tribble Genetics Instructions Step 1. Determine the genotype and phenotype of your F 1 tribbles based on inheritance of traits from purebred dominant and recessive parent tribbles. One tribble should be male and one female, Step 2. Draw your F 1 tribbles portraits. Step 3. Mate your tribbles using a coin to determine the inheritance of traits in the F 2 generation. Step. Draw the tribble offspring portraits. Step 5. Organize the tribble portraits into a pedigree chart. Tribble Genotypes and Phenotypes Dominant Phenotypes Recessive Phenotypes Trait Phenotype Allele Genotype Trait Phenotype Allele Genotype Blue B BB, Bb White b bb Round R RR, Rr Square r rr Triangular T TT, Tt Oval t tt Fang F FF, Ff Square f ff Genotype Phenotype Male XY Straight hair XX Curly hair Punnett Square for Generation Complete the Punnett square for the cross of purebred dominant tribble with a purebred recessive tribble. NOTE: is neither recessive, nor dominant. XX is female. XY is male. (B, b) (X,Y) (R,r) (T,t) (F,f) What will the F 1 offspring look like? Why?

2 Draw the faces of the F1 offspring. Purebred Recessive Generation Purebred Dominant F 1 Generation Male Complete the Genotype and Phenotype s of the F 1 generation. F 1 Male F 1 Trait Phenotype Genotype Trait Phenotype Genotype If the F1 offspring are mated, what will the F2 offspring look like? Complete the Punnett Square for each trait using the F 1 tribble genotypes. (B, b) (X,Y) (R,r) (T,t) (F,f)

3 Tribble Genetics Worksheet for F2 Tribbles Complete the table for each F 2 offspring phenotypes and genotypes. Use a coin to determine which allele is inherited from each parent. For gender, all offspring inherit an X chromosome from the female parent. Flip the coin once to determine whether the offspring inherits an X or Y chromosome from the male parent. Let tails= Y and heads = X. There is no dominant or recessive allele for gender. Other Traits For color, eyes, nose, and teeth, you will need to flip the coin once for the allele inherited from the male parent, and once for the allele inherited from the female parent. Let heads = dominant and tails = recessive; You are now ready to complete the final step, the pedigree.

4 Tribble Pedigree Layout instructions Tribble Pedigree Male Use the title Tribble Pedigree. 2. Place the F 1 parent pets below the title. 3. Label the parents as Male and.. Connect the parents to the offspring using the lines as shown. 5. Label each offspring. Be careful that they match your chart. 6. Attach the final chart of phenotypes and genotypes. Make sure your name and your partner s name are on the chart of phenotypes and genotypes. Grading Notes Each Punnett square is worth 1 point. The square is either correct or incorrect. Genotypes and phenotypes must match to be correct. Phenotypes and portrait features must match to be correct. Points will be deducted for: More than 3 teeth More than one curl or straight hair Additional features such as braces, glasses, bows, tattoos, eyebrows coloring in noses or teeth as these are not considered species characteristics of the Tribbles. Any unnecessary decoration or writing

5 Grading Rubric Category Score Male Tribble Phenotype Male Tribble Tribble Phenotype Tribble Punnett Squares Pedigree Following directions No 1 deduction 2 3 More than Add on 10 points 8 points 6 points points 2 points 0 points Add on Maximum Score = 100 points Total Score