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Corn kernel activity. 3/27 ATB. What carries your genetic code? Today: Look over tests Start new chapter!. Chapter 11 Review. What are autosomes? What does diploid mean? What is the difference between the cells produced in mitosis and meiosis? What is the purpose of mitosis
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3/27 ATB • What carries your genetic code? • Today: • Look over tests • Start new chapter!
Chapter 11 Review • What are autosomes? • What does diploid mean? • What is the difference between the cells produced in mitosis and meiosis? • What is the purpose of mitosis • How many sex chromosomes do you have? • How many sex cells do you have? • What is the purpose of meiosis? • What is crossing over? • What are homologous chromosomes?
3/28 ATB • What type of plant did Mendel use in his experiments? • Today: • Show me your completed page 2 and 3 of your note packet • First 15 minutes…complete the book assignment on page 3 of your note packet • Rest of class…start the new chapter on genetics
What is genetics? • Scientific study of heredity • Helps us understand what makes organisms unique
Brief History • Gregor Mendel – Austrian monk • One of 1st to study heredity • Heredity - Transmission of characteristics from parents to offspring – studied pea plants • Trait – genetically determined form of a characteristic • Examples: Yellow color, pea shape (shriveled or round)
True Breeding • What does it mean that Mendeal had peas that were “true breeding”? • plants that, when self pollinated, always produce the same traits
Pollination Fertilization – • When a male and female sex gametes fuse. Self-Pollination – • when pollen is transferred to the stigma of the same plant Describe a trait • Specific characteristic of an individual • Examples: Seed color or plant height
Pollination – • when pollen is transferred from the anther of a flower to the stigma • Cross-Pollination – • when pollen is transferred to the stigma of a different plant
Genes and Alleles • P generation – parent generation • F1 Generation – 1st “filial” generation – offspring of the P generation (means son / daughter) • F2 Generation – 2nd “filial” generation – offspring of the F1generation • What are genes? • Factors that determine an individuals characteristics • Alleles– various forms of a trait • Allele for pea pod color – G = green and g = yellow
Dominant and Recessive Alleles • What does the Principle of Dominance State? • Some alleles are dominant and others are recessive • Dominant – alleles that are always expressed (mask recessive) • Recessive – alleles that are masked by dominant alleles • Example: Pea pod color • G = green pods • g = yellow pods • What will these offspring look like? • GG • gg • Gg
Segregation • Segregation of Alleles • Alleles for height segregate (or separate) during gamete formation • What are gametes? • Sex cells • This is saying that during gamete formation, the alleles for each gene segregate from each other so that each gamete only carries one allele for each gene • So a sex cell can’t carry the 2 alleles for being tall
4/18 ATB • A protein in a cell membrane changed its shape to move sodium and potassium ions against their concentration gradients. Which molecule was MOST LIKELY use by the protein as an energy source • A) ATP • B) ADP • C) catalase • D) amylase • Today: • Monohybrid cross perfection • Go over tests
3/31 • What does true breeding mean? • Today: • Review genetics • Start punnett squares
Probability • What is probability? • Likelihood that an event will occur. • Cup game and probability!
Heterozygous – • when alleles for a trait are different (Gg) Homozygous – • when alleles for a trait are the same (GG or gg) Genotype – • genetic make up (Gg) Phenotype – • organisms appearance (Green)
Monohybrid Cross – • when you make a cross for only one trait • Example: • Trait = pod color • Cross: Yellow Pod x Green Pod Punnett Square – • diagram used to show results of crosses
Monohybrid Cross Practice T = tall t = short R = round r = wrinkled W = white w = purple 1. Cross the following: TT x tt. • What is the genotype ratio? • What is the phenotype ratio?
2. Cross a heterozygous round plant with another heterozygous round plant. • What is the genotypic ratio? • What is the phenotypic ratio?
3. Cross a heterozygous white plant with a purple plant • What is the genotypic ratio? • What is the phenotypic ratio?
4/19 ATB • Make a punnett square to complete the following cross. T = tall t = short • Cross a heterozygous plant with a short plant. What are the genotypic and phenotypic ratios? • Today: • Finish discussion on monohybrid crosses • Today is the last day we will really focus on the monohybrid crosses
Worksheet pages • You must complete by the end of the period: • Page 10, 15, 16, 21, 22 • Pg 28-29 – homework
4/22 ATB • What is the phenotypic ratio of a cross of two heterozygous plants? • Today: • Go over worksheets from Friday • Homework: Page 28-29. • Discuss incomplete dominance / codominance • Test – Thursday
Test Cross – • Cross done to find the genotype of an organism • Cross the unknown with a homozygous recessive
Law of segregation – • Alleles for a trait separate during gamete formation • So when we’re making our sex cells, the alleles (for forms of a trait) separate and are inherited independently (so a male pollen grain may have the allele for being green OR being yellow)
Law of Segregation – • alleles from parents separate during gamete formation • A) Copy of gene separates – so each sex cell only receives one copy • (So a parent with GG donates “G” to one gamete and the other “G” another.)
Law of Independent assortment – • Genes for different traits are transmitted independently of one another • Means that different traits are not inherited together.
Dihybrid Crosses • Dihybrid Cross – • when you make a cross for two traits • Example: • Pod color AND plant height • Flower color AND pod shape. • Cross: Tall, Yellow Plant x Short, Green Plant
Cross a short, purple plant with a homozygous tall, heterozygous white plant. What is the phenotypic / genotypic ratios?
Dihybrid Cross Practice T = tall t = short W = white w = purple Cross a heterozygous tall, white plant with another heterozygous tall, white plant. What is the phenotypic / genotypic ratios?
Dihybrid cross practice • Bottom of page 13 • Page 26