Transcript 1 RR
1. Who is named the “Father of Genetics?” 2. Why did he use pea plants? 1. Gregor Mendel 2. To study the inheritance of traits and they reproduced quickly 1. What is pure bred, true breeding, or homozygous mean? 2. What type of offspring results when you cross two pure “true” breeding parents with different traits? 3. What are the offspring of two parents called? 1. Both alleles are either dominant or recessive AA or aa 2. All hybrid (Aa) offspring result 3. F1 generation Aa What results when the offspring (F1) of true breeding parents self-pollinate? Rr x Rr R r R RR Rr r Rr rr Genotype Ratio: 1 RR: 2 Rr: 1 rr Phenotype Ratio: 3 Round: 1 Wrinkled 1. What is probability? 2. What is the probability of getting heads when you flip a penny? 1. Probability: The chance of something happening! 2. ½ or 50% Why did we keep increasing the number of flips of our penny in the “Coin Toss” lab? The higher the number of trials you perform, the more likely you are to get the expected outcome (probability). ½ heads, ½ tails If you toss a coin 6 times in a row, what is the probability it will land heads for all 6 tosses? If you toss a coin 6 times in a row, what is the probability it will land heads for all 6 tosses? ½ x ½ x ½ x ½ x ½ x ½ = 1/64 What is the “Principle of Independent Assortment?” During gamete formation, genes for different traits separate without influencing the other. Foil each parent to get 4 gametes GgYy GY Gy gY gy Be able to define: Complete Dominance Incomplete Dominance Co-Dominance Complete Dominance The dominant trait (G) over shadows the recessive trait (g) and only the dominant trait shows up in the phenotype. Incomplete Dominance Neither trait is dominant over the other and a new trait is displayed. BLENDING!!! Red flowers crossed with white flowers make pink flowers. Co-Dominance Both traits are equally displayed and neither is dominant over the other. ABO blood types: A blood x B blood = AB blood Describe the genotypes and phenotypes of each blood type: Type A Type B Type AB Type O Describe the genotypes and phenotypes of each blood type: AB has same genotype and phenotype What are polygenic traits? What are polygenic traits? Traits that have a wide variety of color ranges such as eye colors, hair color, skin color. How many different gametes would you get from the following parent? AABbCcDdEEFFGgHh First determine how many different letters are there for each letter type then multiply! AABbCcDdEEFFGgHh 1x2 x2 x2x1x1x2x2= 32 gametes Can this parent AaBBccDdeeFfGgHH have a child with the following genotype? Why or why not? AABbCcDdEEFFGgHh Can this parent AaBBccDdeeFfGgHH have a child with the following genotype? Why? NO, because the parent would need to have a big E in their genotype in order for the child to have 2 EE’s. AABbCcDdEEFFGgHh Know what forms from the sex cells in females and males! Male 4 Sperm are produced Female 1 Egg and 3 polar bodies are produced Know the stages of Meiosis I & II The paired, homologous chromosomes come together during Meiosis I to make Tetrads The chromatids pull apart during Meiosis I I 4 genetically different cells result at the end of Meiosis Haploid = one set of chromosomes When does crossing over occur during Meiosis? Why is this important? During Prophase I Important for GENETIC DIVERSITY!! X S Xt X X T s Diploid Parent SsTt XX S s XX t T What are the four possible combinations for the haploid cells? XX S l l S S T T t ST s XX t l l l l T s St l l t s sT st 1.What is this picture called? 2.What 4 things are shown from this picture? 1.What is this called? Karyotype 2.Shows: • Autosomes = all chromosomes # 1 - 22 chromosome pairs (not sex chromosomes) • Sex Chromosomes (XX= female or XY= male) # 23 pair • Homologous Chromosomes = chromosomes that code for the same traits and pair up with each other • Inherited Disorders (ex: Down’s, Turner’s, Kleinfelter’s, Super males/females) What is non-disjunction? Non-disjunction –When chromosome pairs don’t separate properly during Meiosis I Can involve all types of chromosomes (sex, autosomes, homologous) What chromosomal disorder is this on the #21 pair? #21 Down’s Syndrome (Trisomy 21) #21 What chromosomal disorder is this on the sex chromosome? XXY Kleinfelter’s Syndrome XXY What chromosomal disorder is this on the sex chromosome? XO Turner’s Syndrome XO Who determines the sex of the offspring? Mother or Father Why? What is probability of getting a girl? A boy? Father determines sex of offspring 50% chance of Boy 50% chance of Girl He provides either an X or a Y to pair up with the mother’s X to make a boy or girl •What is this picture called? •What do each of the shapes and shading combinations represent? •How many generations are shown? Normal Male Normal Female Female with Trait Pedigree Chart = shows how a trait is passed from one generation to the next. 3 Generations Carrier Female Male with Trait Carrier Male Line = Marriage Be able to describe the differences between: Meiosis and Mitosis Be able to describe the advantages and disadvantages between: Asexual and Sexual Reproduction Mitosis Meiosis Somatic Cells – all body cells 2 cells are made Sex Cells - gametes Diploid Haploid Asexual Reproduction Sexual Reproduction Advantages No mate needed for reproduction Very fast reproduction time Lots of organisms Disadvantages All organisms are alike, No Genetic Diversity 4 cells are made Advantages GENETIC DIVERSITY! Disadvantages Need a mate for reproduction Slower reproduction time Fewer organisms Know the term Sex-linked genes/traits and how the key and Punnett square would look. What chromosome carries these types of traits? XBXb x XbY female carrier x male colorblind XB ? Xb Xb XBXb XbXb Y XBY ? XbY Phenotypes: 1 Female/Carrier 1 Female/Colorblind 1 Male/Normal 1 Male/Colorblind Know the term Sex-linked genes/traits and how the key and Punnett square would look. What chromosome carries these types of traits? Sex-linked gene/trait – Traits linked to sex chromosomes such as hemophilia or colorblindness XBXb x XbY female carrier x male colorblind XB Xb Xb XBXb XbXb Y XBY XbY Phenotypes: 1 Female/Carrier 1 Female/Colorblind 1 Male/Normal 1 Male/Colorblind Sex-linked traits only carried on X Y doesn’t carry traits Know the definitions of the following vocabulary terms: •Allele •Gametes •Genes •Genetics •Karyotype •Pedigree •Probability •Punnett Square •Allele- Different forms of a gene •Gametes- Sex Cells (egg & sperm) •Gene- Part of a chromosome; codes for traits •Genetics- Study of how traits are passed generation to generation • Karyotype- Picture of all chromosomes matched up - looking for sex and the presence of abnormal # of chromosomes •Pedigree- Family tree (picture) shows passing of trait from one generation to the next generation •Probability - Chance of something happening •Punnett Square- Chart showing offspring’s trait probabilities Know the definitions of the following vocabulary terms: •Dominant •Recessive •Genotype •Phenotype •Heterozygous •Homozygous •Trait •Homologous •Dominant – Gene whose effect masks the partner (recessive) trait •Recessive – Gene whose effect is masked by partner (dominant) trait •Genotype – Genetic makeup of organism (letters) •Phenotype – Trait expressed “physical” looks •Heterozygous – Pair of different alleles (Rr) •Homozygous – Pair of same kind of alleles (RR) (rr) •Trait – Inherited characteristic (feature) •Homologous – Pair of same kind of chromosomes Know the definitions of the following vocabulary terms: •Co-dominance •Incomplete dominance •Diploid •Haploid •Independent Assortment •Non-disjunction •Segregation •Co-dominance – Both alleles expressed EQUALLY •Incomplete dominance – Blending of traits •Diploid – Having 2 sets of chromosomes •Haploid – Having 1 set of chromosomes •Independent Assortment – Genes that separate have no effect on the other’s inheritance •Non-disjunction – When chromosomes don’t separate •Segregation – Separation of alleles Understand which is the P, F1, F2 generations and how you get each. Know how to do the following types of crosses: •Monohybrid Cross •Dihybrid Cross •Incomplete Dominance Cross •Sex-linked Cross Must show key, parents’ genotypes, possible gametes, Punnett square, genotypes and phenotypes of offspring Doing the different types of Punnett Squares!