Transcript Slide 1
1. Who is named the “Father of Genetics?” 2. Why did he use pea plants? 1. Who is named the “Father of Genetics?” Gregor Mendel 2. Why did he use pea plants? To study the inheritance of traits What do pure bred, true breeding, and homozygous mean? What do pure bred, true breeding, and homozygous mean? All mean the same thing… Both alleles are either capitals or lower case. AA or aa What do hybrid and heterozygous mean? What do hybrid and heterozygous mean? Actually mean the same thing… A a 2 Alleles are different A a A a What do we call the offspring when you cross two pure “true” breeding parents with different traits? GG x gg What do we call the offspring when you cross two pure “true” breeding parents with different traits? All HYBRID (Gg) offspring result Offspring of two parents (P) are called ____. TT x tt 4 Tt “P” generation “?” generation Offspring of two parents (P) are called ____. TT x tt 4 Tt “P” Generation “F1” Generation What results when the offspring (F1) of true breeding parents self-pollinate (breed with themselves)? TT x tt (P) Hint: Do a Punnett Square!!! Tt (F1) Tt x Tf (F1 x F1) ? What results when the offspring Tt (F1) of true breeding parents self-pollinate (breed with themselves)? Tt x Tt T t T TT Tt t TT Tt Genotype Ratio: 1 RR: 2 Rr: 1 rr Phenotype Ratio: 3 Round: 1 Wrinkled What is probability? What is the probability of getting heads when you flip a penny? Probability= The chance of something happening! Chance of getting heads ½ or 50% Why did we keep increasing the number of flips in the “Coin Toss” lab? More times you flip a penny, 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: • Compete Dominance • Incomplete Dominance • Co-Dominance Complete Dominance The dominant trait (G) masks (hides) 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: Co-Dominance AB has same Genotype & Phenotype What are polygenic traits? What are polygenic traits? Traits that have a wide variety of color ranges such as eye color, hair color, skin color and height. How many different gametes would you get from the following parent? AABbCcDdEEFFGgHh How many different gametes? 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 or why not? NO, because the parent would need to have a big E in their genotype in order for the child to have both big E’s. AABbCcDdEEFFGgHh What process forms 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? Crossing Over During Prophase I Important for GENETIC DIVERSITY!! What are the chromosome pairs for a … FEMALE? MALE? What are the chromosome pairs for a … FEMALE XX MALE XY What is this picture called? What 4 things are shown from this picture? What is this called? Karyotype 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/Super females) What is non-disjunction? Non-disjunction –When chromosome pairs don’t separate properly during Meiosis I Can involve all chromosomes (sex, autosomes, homologous) What chromosomal disorder is shown? Down’s Syndrome (Trisomy 21) What chromosomal disorder is shown? Kleinfelter’s Syndrome XXY What chromosomal disorder is shown? 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 XY 50% chance of Girl XX Father 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 and shows? •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 •Shows male or female •Shows “no trait” “carries trait” or “has trait” Carrier Female Male with Trait 4 Generations shown 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 MUST KNOW ALL OF THIS INFORMATION!!!!! MITOSIS vs MEIOSIS Mitosis Meiosis Somatic Cells – All body cells 2 cells are made: Identical Sex Cells – Gametes (sperm and egg) 4 cells are made: All different Diploid “2N” Haploid “N” 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 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 Carrier Female x Male Colorblind Sex-linked traits only carried on X Y doesn’t carry traits! XB Xb Xb XBXb XbXb Y XBY XbY Phenotypes: 1 Female/Carrier 1 Female/Colorblind 1 Male/Normal 1 Male/Colorblind 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 a trait •Genetics- Study of how traits are passed generation to generation • Karyotype- Picture of all paired chromosomes looking for sex and the presence of abnormal # of chromosomes •Pedigree- Chart that shows passing of trait from one generation to the next generation •Probability - Chance of something happening •Punnett Square- Chart showing possible offspring from a parent cross. 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; gene type •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 Di-Hybrid Cross Incomplete Dominance Complete Dominance Sex-Linked Cross Doing the different types of Punnett Squares!