1 / 32

What is the probability of rolling a 1 and 5 in two separate rolls?

What is the probability of rolling a 1 and 5 in two separate rolls?. Agenda for Tuesday March 30 th Mendel notes Punnett Squares. Law of Segregation. Chromosomes separate during meiosis and unite during fertilization. Law of Independent Assortment.

solada
Télécharger la présentation

What is the probability of rolling a 1 and 5 in two separate rolls?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. What is the probability of rolling a 1 and 5 in two separate rolls? Agenda for Tuesday March 30th • Mendel notes • Punnett Squares

  2. Law of Segregation • Chromosomes separate during meiosis and unite during fertilization

  3. Law of Independent Assortment • Random distribution of chromosomes occurring during meiosis • Genes on separate chromosomes sort independently

  4. The point? • It’s all random • Which alleles we get (genes) (traits) • Crossing over • Etc.

  5. What is a trait? Agenda for Thursday March 31st • Mendel • Punnett Squares

  6. Mendel • Father of genetics • Loved nature • Austrian monk • taught natural science • worked on plant breeding experiments using pea plants • Developed basic understanding of genetics and inheritance

  7. Mendel’s Work • It took him 2 years to select the pea plant • He collected data for 10 years. • His sample sizes were large; he tabulated results from 28,000 pea plants. • He replicated his experiments. • Published work but was dismissed • Found later

  8. Mendel’s Experiment • P Generation – parent generation • F1 generation – first filial generation, offspring of parents • F2 generation – second filial generation, offspring of F1 generation • Ratio of 3:1

  9. Mendel’s Results

  10. Collected 6022 yellow and 2001 green 3:1 ratio

  11. Conclusions • 2 forms of seed traits in the pea plants • Alleles – forms of a gene passed on to each generation • Green and yellow pea seeds • We use letters to represents alleles/genes/traits • Individuals are diploid so we use 2 letters **Genes are on the chromosomes

  12. Dominant and Recessive • Dominant – the trait we see (expressed with capital letter, A) • Recessive – trait that is masked (expressed with lower case letter, a) • Which is better, dominant or recessive?

  13. Dominance • Mendel’s experiment, green color was masked • Recessive • Organism with two of the same allele – homozygous • AA, aa • Organism with two different alleles – heterozygous • Aa • Dominant trait observed (notice the dominant allele)

  14. Homozygous (pure bred) Same HH hh

  15. Heterozygous (hybrid) Different Hh Rr

  16. Genotype Allele makeup of an individual Tt T T tt RR Rr rr

  17. Phenotype Observable characteristics of an individual

  18. Punnett Squares Let’s Practice

  19. Practice A Tt (tall) plant is crossed with a tt (short plant). What percentage of the offspring will be tall? A green pea sead (gg) is crossed with a hybrid yellow seed (Gg). What will be the genotypic and phenotypic ratios of the offspring?

  20. Practice A heterozygous plant (Tt) is crossed with another heterozygous (Tt) plant. What percentage of the offspring will be tall? In guinea pigs, rough coats are dominant over smooth coats. If an Rr guinea pig is crossed with an Rr guinea pig. What are the chances of each genotype and phenotype? Include genotypic and phenotypic ratios.

  21. Define homozygous, heterozygous, phenotype, and genotype Agenda for Friday April 1st 1.Quiz 2. More practice with Punnett Squares

  22. A Tt (tall) plant is crossed with a tt (short plant). What percentage of the offspring will be tall? • Quiz • Review Punnett Squares • Making Dragons

  23. Making Dragons

  24. A Rr (round) seed is crossed with a Rr (round plant). What are the phenotypic and genotypic ratios? • Finish making dragons • Comparing ratios of Punnett squares to actual ratios lab

  25. What is the process of combining two gametes called? • Finish Comparing Punnett Square ratios • Dihybrid Crosses

  26. Dihybrid Cross • a cross between of two individuals that differ in two traits of particular interest For example: GGbb/ggBb or RRYY/rryy

  27. What is a dihybrid cross? • Dihybrid Review • Gene Linkage and Polyploidy • Mapping Chromosomes

  28. Genetic Recombination • New combination of genes produced by crossing over and independent assortment Why is genetic recombination important?

  29. Gene Linkage • Genes on same chromosomes are said to be linked • Travel together during Meiosis • Not always true – crossing over occurs • Genes close together cross over more frequently • Make chromosome maps based on that info.

  30. Chromosome Map • Map genes A, B, C, D • Frequency of crossing over • AD = 25% • AB = 30% • CD = 15% • BD = 5% • BC = 20%

  31. Polyploidy • Most cells are Diploid (2n) • Polyploidy – one or more extra sets of chromosomes • Triploid – 3n • In humans polyploidy is lethal • Other organisms it is not • Roughly 1 in 3 plants are polyploidy • Increased vigor and size

More Related