University:
Minnesota State University Moorhead
Course:
BIOL-341 | Genetics
Academic year:

2022
Views:

256

Pages:

3
Author:

Kaiden Murphy

Name: Date: More Punnett Square Practice 11.2 A punnett square helps scientists predict the possible genotypes and phenotypes of offspring when they know the genotypes of the parents. The phenotype is the physical appearance of an organism and the genotype is the inherited combination of alleles. This skill sheet will give you additional practice in using punnett squares to solve genetics problems. In rabbits, black fur is dominant to white fur. If you cross a BB male with a Bb female, what are the possible genotypes and phenotypes of the offspring? What is the percent chance for each type? Solution: 1. B B B BB BB b Bb Bb Genotype Phenotype Chance BB Black fur 50% Bb Black fur 50% In cabbage butterflies, White wings are dominant to yellow wings. If a Ww butterfly is crossed with a ww butterfly, what are the possible genotypes and phenotypes of the offspring and the percent chance for each? W w w w Ww ww Ww ww Fill in the table: Genotype Ww ww Phenotype White Wing Yellow Wings Chance 50% 50% Page 2 of 3 2. In dogs, there is a hereditary type of deafness caused by a recessive gene. Two dogs who carry the gene for deafness but have normal hearing are mated. What are the possible genotypes and phenotypes of their offspring and the percent chance for each? D 11.2 d D DD Dd d Dd dd Fill in the table: Genotype 3. Phenotype DD Normal hearing Dd Deafness dd Deafness Chance 25% 50% 25% In guinea pigs, short hair is dominant over long hair. If a short haired SS guinea pig is crossed with a long haired ss guinea pig, what are the possible genotypes and phenotypes of their offspring and the percent chance of each? S S s Ss Ss s Ss Ss Fill in the table: Genotype Phenotype Ss short haired Ss Short Haired Chance 100% 100% Page 3 of 3 4. Can you curl your tongue up on the sides? Tongue-curling in humans is a dominant genetic trait. Suppose a man who is Tt for tongue-curling marries a woman who is also Tt for this trait. What are the possible genotypes and phenotypes of their children and the percent chance for each? T 11.2 t T TT Tt t Tt tt Fill in the table: Genotype TT Tt tt 5. Phenotype Chance tongue curling 25% tongue curling 50% not tongue curling 25% In guinea pigs, rough coats (with lots of swirly cowlicks) are dominant over smooth coats. If an RR guinea pig is crossed with a Rr guinea pig, what are the possible genotypes and phenotypes of the offspring? What are the chances of each? R R r RR Rr R RR Rr Fill in the table: Genotype Phenotype Chance RR swirly coat 50% Rr not swirly 50%