Tuesday, December 6, 2011 Name: ____________________________________ Period: ____ Describe heredity as the passage of instructions from one generation Competency to another and recognize that heredity information is contained in 3d – DOK 2 genes, located in the chromosomes of each cell. 8th Grade – I can calculate percentages and numbers of offspring with a specific Lesson 5.5 genotype and phenotype. Page 5 Unit 5 – Heredity and Genetics: Percentages, Numbers, and Punnett Squares Quick Review A substance turns red litmus paper blue. It also dissociates very easily in water. Use this information to answer the following questions. 1. How could this substance be classified? base 2. What is the range of possible pH for the substance? >7 3. When the substance is mixed with water, it releases what atom or molecule? OH4. What two groups on the periodic table could it be made from? Alkali metals and alkali earth metals 5. This substance is a (strong or weak) (acid or base). Key Points on Percentages, Numbers, and Punnett Squares 1. What a. A Punnett square can be used to determine the chance of a single offspring having a certain genotype or phenotype. b. If a cross produces a large number of offspring, a Punnett square can also be used to predict the number of offspring with a certain genotype or phenotype. 2. How Plankton, a character from SpongeBob, is a. Write down the genotypes of the green in color. This trait is given by the parents that are being crossed. b. Fill in the Punnett square according to dominant allele of the color gene in his species. The recessive allele gives a pink the instructions in lesson 5.4 organism. If Plankton, a heterozygote, is c. Determine the specific phenotype or crossed with a pink plankton, what chance genotype the question is asking you to will their offspring have of being pink? determine. Cross: X d. Create a ratio for this phenotype of genotype. Punnett Square: e. Convert to number or percentage i. Chance that a single offspring will have the given phenotype of genotype = percentage. a) Convert fraction to a decimal b) Move decimal two places Trait of offspring being studied: right and add percent sign. ii. Number of offspring with a trait = Ratio: setup proportion using the ratio Number of Offspring or Percentage Chance? and the total number of Answer: offspring. Tuesday, December 6, 2011 Name: ____________________________________ Period: ____ Describe heredity as the passage of instructions from one generation Competency to another and recognize that heredity information is contained in 3d – DOK 2 genes, located in the chromosomes of each cell. th 8 Grade – I can calculate percentages and numbers of offspring with a specific Lesson 5.5 genotype and phenotype. Page 5 Unit 5 – Heredity and Genetics: Percentages, Numbers, and Punnett Squares Quick Review A substance turns red litmus paper blue. It also dissociates very easily in water. Use this information to answer the following questions. 1. How could this substance be classified? 2. What is the range of possible pH for the substance? 3. When the substance is mixed with water, it releases what atom or molecule? 4. What two groups on the periodic table could it be made from? and 5. This substance is a ( or weak) (acid or ). Key Points on Percentages, Numbers, and Punnett Squares 1. What a. A Punnett square can be used to determine the of a having a certain or . b. If a cross produces a large number of offspring, a Punnett square can also be used to the number of offspring with a certain or . 2. How a. Write down the of the Plankton, a character from SpongeBob, is green in color. This trait is given by the parents that are being . dominant allele of the color gene in his b. the Punnett square according to the instructions in lesson 5.4 species. The recessive allele gives a pink organism. If Plankton, a heterozygote, is c. Determine the crossed with a pink plankton, what chance or the question is asking will their offspring have of being pink? you to determine. Cross: X d. Create a for this phenotype of Punnett Square: genotype. e. Convert to or i. Chance that a will have the given phenotype of genotype = . a) Convert to a Trait of offspring being studied: b) Move decimal places and add percent . Ratio: ii. Number of offspring with a trait = Number of Offspring or Percentage Chance? setup using the Answer: and the number of . Tuesday, December 6, 2011 Name: ____________________________________ Period: ____ Punnett Square Introduction: Guided Practice Gene Body Shape Body Color Eye Shape Nose Style Dominant Allele SquarePants (S) Yellow (Y) Round (R) Long (L) SpongeBob’s aunt and uncle, SpongeWilma and SpongeWilbur, have different shaped eyes. Wilma is believed to be homozygous for her round eyes, while Wilbur has oval eyes. If Wilma and Wilbur have eight children how many would be expected to have oval eyes? Recessive Allele RoundPants (s) Blue (y) Oval (r) Stubby (l) If SpongeBob and his new wife, SpongeSusie, are both heterozygous for yellow body color, what is the percentage chance that their offspring will be blue? Punnett Square Introduction: Independent Practice 1. SpongeBob’s aunt is famous around town for her itty, bitty stubby nose! She recently met a fellow who also has a stubby nose. What chance would their offspring have of being homozygous dominant? 2. SpongeBob and his wife, SpongeSusie, are carriers of the recessive RoundPants allele. SpongeSusie has found out she is pregnant. What is the chance that they will have a RoundPants child?