Genetics Questions If you still have questions on
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Genetics
Questions? If you still have questions on Punnett squares and genetics once you’ve been through the Power. Point, watch YOUTUBE videos. Also, write down you questions for me to answer in class. Here a couple helpful You. Tube Link: • https: //www. youtube. com/watch? gl=US&hl=en&client=mvgoogle&feature=fvwrel&v=prk. HKjf. Um. Ms&rl=yes&nomobile=1 • https: //www. youtube. com/watch? v=i-0 r. Sv 6 ox. SY
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On an even page in your notebook draw the picture to the right and fill in each line with descriptions from the list below. • • • Genotype Phenotype Trait Purebred Hybrid Homozygous Dominant Homozygous Recessive Heterozygous Allele Dominant Allele Recessive Allele Genotype Homozygous Dominant Homozygous Recessive Purebred Trait Heterozygous Hybrid Phenotype Trait Genotype Allele Trait Dominant Allele Genotype Hybrid Heterozygous Phenotype Trait
Traits Answer the following questions beside your chart. 1. What is the difference between a dominant Detached Earlobes and recessive allele? • The dominant allele is always expressed when present (HH , Hh). • The recessive allele is only expressed when the dominant is absent (hh). Traits Dimples Attached Earlobe No Dimples Freckles No Freckles Cleft Chin No cleft 2. If you were a scientist and only had a chart of Brown / a populations traits, how could you decide Black hair what traits were dominant and what were recessive? Brown Eyes • The traits that had the highest number in the population would be dominant. There are three different genotype combinations HH , Hh , hh. The dominant allele has a 2/3 chance of being expressed over a recessives 1/3 chance. # Blonde Hair Gray / Blue Eyes #
Punnett square #2 is incorrect. The Alleles move straight down or straight across. They can not be moved diagonal The upper case A is into the Punnett square. incorrect. It should be two lower case a’s a A a a Aa Aa aa aa 1 A a a a Aa aa Aa Aa 2 A a aa Aa 3
How to complete a Punnett Square – Write on blank side of half sheet Step 1 – Draw the 4 square Step 2 – Put parent allele’s on the outside of Punnett square. Trait – Eye Color Alleles - Brown Eyes and Blue Eyes E = Brown e= blue Male / Father alleles Female / Mom Alleles E e
Step 3 - Bring dad alleles down - Bring mom alleles across Step 4 - Determine probability/percentage of each genotype Percentage 75% chance of brown eyes 25% chance of blue eyes Male / Father alleles Female / Mom Alleles E e EE Ee Ee ee Trait – Eye Color Alleles - Brown Eyes and Blue Eyes E = Brown e= blue
g G g Gg g gg is homozygous recessive and 50% gg 50% T t t T Tt Tt 100% tt is homozygous recessive and 0 %