Presentation on theme: "Do Now: If the world were hit with a massive outbreak of a disease like Bubonic Plague. What would the impact be on human?"— Presentation transcript:
Do Now: If the world were hit with a massive outbreak of a disease like Bubonic Plague. What would the impact be on human?
Homework – Thursday’s class Review your tests, make corrections and be ready to re-take the test tonight at 7:45.in the Biology room. Read pages 338 – 343 Define these terms: Transformation Bacteriophage
Review Write these questions and be prepared to answer them: Why did Gregor Mendel choose the Pea to study genetics and what did he find? –The pea has a simple design. –Fertilization - –Hybrids –Pollination –Gametes
Review What is heredity: The sum of the characteristics and potentialities genetically derived from one's ancestors What are traits? The specific characteristic of an organism such as height, or color What is the Law of Segregation? Each parent passes along one trait (allele) to the off-spring What is the difference between Genotype & Phenotype? Genotype = the genetic make up. For example blonde hair would be bb, meaning two recessive genes. Phenotype = actual physical characteristics. In this case blonde hair.
Review Genotype – the genetic makeup of a gene (TT, Tt, tt) Homozygous –Same type of alleles (Tall – Tall= TT) or (short- short=tt) Heterozygous – both different (Tall-short = Tt).
Review What is the difference between Homozygous & Heterozygous? Homozygous are genotypes that are the same and either dominant or recessive, not one of each. For Example – blonde hair (bb) or Brown hair (BB). Heterozygous are genotypes that are both different, meaning one dominant and one recessive. Mendel’s law of Dominance would simply be that although two different genotypes are present, the dominant gene would expressive itself. The recessive would just be passed along without being expressed.
Review This is an example of what? (Two possible answers) Inbreeding and / or Genetic Drift
Small gene pool / inbreeding Inbreeding and / or Genetic Drift aka the Founder’s Effect. A small isolated community will naturally have less genetic diversity. Some random and / or rare conditions tend to appear more often. For example the British Royal Family and hemophilia.
Dihybrid Di-hybrid – deals with two traits. (p. 316) – each box will have 4 alleles = BbTt X BbTt. B- Brown Hair, b – Red Hair, T – Tall, t – Short
Dihybrid Do the following - BbTt X BbTt. B- Brown Hair, b – Red Hair, T – Tall, t – Short BTbTBtbt BT bT Bt bt
Ratios How many Brown Hair and Tall will you have? 9 How many Brown Hair & short 3 How many Red Hair & Tall 3 How many Red Hair & short 1
Review stuff What is Co-Dominance? Both are expressed equally. Incomplete Dominance? Neither one is fully expressed, they are blended (meaning neither red nor white is expressed, but the blending in this case pink.
Dominant vs Recessive Hitler’s hope was to have his “super race” by creating genes that were recessive, which he considered to be “pure”. Explain why he felt that the use of recessive genes was “pure?” Because on the rarity of the traits. Also, once doing the Di-Hybrid (16 box Punnett Square) there is only one totally recessive box. That recessive cannot be altered or in his mind corrupted. There is no way to tell if someone with brown hair is homozygous (BB) or heterozygous (Bb). Very easy to see Blonde hair - bb
Principle of Dominance Principle of Dominance. Create a scenario that illustrates the Principle of Dominance. Blue eyed mom (bb) homozygous and brown eyed dad (you pick either heterozygous (Bb) or homozygous (BB). Use the punnet square below.
Before leaving Before you leave, clean up the area around your table. Make sure you have the homework(s) for tonight.