2. The study of heredity, transfer of characteristics from parent to offspring.

3.  New Journal Entries

4. Entry 33 10/18 Genotype vs. Phenotype  Genotype is the genetic makeup (AA, Aa, or aa)  Phenotype is the physical trait, a result of the genotype Allele For any trait, such as hair color, there are different forms of the protein that create the different hair colors. Each different form is called an allele. We use capital letters to represent dominant alleles and lower case letters to represent the recessive alleles. Copy the vocabulary in your journal

5. A. The Father of Genetics:  Gregor Mendel is known as the Father of Genetics. He studied pea plants, because they were easy to observe and reproduce. Knowing that the male part of the plant produced sperm, and that the female part produced the egg, he was able to join the two reproductive cells. This is called fertilization.

6. B. Inheritance of chromosomes  Egg + sperm  zygote (earliest stage of development) (meiosis)  (fertilization)  (mitosis and development) egg sperm zygote fertilization mitosis & development meiosis

7. B. Inheritance of Chromosomes  Chromosomes exist in pairs, one from sperm and one from egg. Known as homologous pairs  A section of DNA within the chromosome that contains the info to make proteins called a gene. Genes determine our traits.  A trait is any physical or physiological characteristics. Ex: eye color, blood type

8.  We will all receive the same type of genes but we can get different versions of a gene called an Allele. Ex: Gene: thumb type. Alleles: Hitchhikers thumb or straight thumb.  Alleles are represented by letters. A dominant allele is written with a capital. A recessive allele is written with a lowercase. Ex: Hitchhikers thumb (A) or straight thumb (a).  *Dominant genes masks/hides recessive.

9.  Genotype describes the 2 alleles you received from mom and dad. Homozygous means you received identical copies (purebred) AA – homozygous dominant aa - homozygous recessive Heterozygous means you got one dominant and one recessive (hybrid); Aa. ○ 2 people can have the same appearance but have different genetics: AA vs Aa.  Phenotype describes how the alleles are portrayed or look physically.

10. Ticket out the Door 1&2 - Identify which picture below represents the phenotype and which represents the genotype?  Match the following… 3. ____ HeterozygousA.) BB 4. ____ Homozygous Dominant B.) Bb 5. ____ Homozygous RecessiveC. ) bb BB Picture APicture B

11. From gene to protein transcription translation protein

12. Entry 3410/19 1&2 - Identify which picture below represents the phenotype and which represents the genotype?  Match the following… 3. ____ HeterozygousA.) BB 4. ____ Homozygous Dominant B.) Bb 5. ____ Homozygous RecessiveC. ) bb BB Picture APicture B

13. D. Mendel’s Three Principles  1. Principle of Dominance: dominant alleles can mask/ hide recessive alleles Genotypes:Phenotypes: Homozygous dominant:(AA)Dominant trait is expressed Heterozygous: (Aa)Dominant trait is expressed Homozygous recessive:(aa)Recessive trait is expressed

14. D. Mendel’s Principles  2. Principle of Segregation: during meiosis the alleles separate so each parent can only pass on one allele per trait. We get half of our genes from each parent.

15. D. Mendel’s Principles 3. Principle of Independent Assortment: genes on separate chromosomes are passed on independently (randomly) from one another.

16. E. Genetic Probability  Punnett squares are used to predict the outcome of fertilization between the gametes. The sides of the Punnett square are labeled with the genotype from each parent (sperm and egg).  Monohybrid Cross- involves only 1 trait.  Dihybrid Cross- involves 2 traits.

17. Mendelian Genetics Ex: Huntington’s disease breaks down the nervous system. It is a dominant trait. If a heterozygous woman marries a man without Huntington's what is the chance their kids will have the disease? _______% What is the phenotypic ratio (compare the result of the genes)? What is the genotypic ratio (compare the genetic combinations)? Mother H h Father ?

18. Entry 3310/19 1.Pick up the assignment on LAB STATION 1 2.Complete 3.Paste in Journal

19. Genetics Group Practice- 10 punnett squares  Draw a card from the gene stack and one from the parent stack  Complete the cross by doing a punnett square (alleles are already assigned, see your instruction sheet)  Complete the Genotype and phenotype ratios  Write what the children will look like: 25% blond hair 75% brown hair

20. Entry 35 10/25  In tomatoes, red fruit (R) is dominant over yellow fruit (r). A plant that is homozygous for red fruit is crossed with a plant that has yellow fruit. What would be the genotype and phenotype of the P1 generation and the genotypic and phenotypic ratio of the F1 generation?  If two of the F1 generation from the above cross were mated, what would be the genotypes and phenotypes of the F2?

21. 5 types Non-Mendelian Inheritance  These traits are NOT just dominant or recessive, there for they do not follow the Mendelian genetics.

22. 1. Codominance: Both alleles are equally dominant and will be expressed (in heterozygote). o Phenotype: both versions of the trait show in the heterozygote o Genotype: use 2 different letters. o Ex: Sickle Cell Anemia is a codominant disorder. This means that you will have normal disk shaped cells (N), and sickle shaped cells (S). o 3 Possibilities: * Heterozygous genotype is resistant to malaria.* GenotypePhenotype NNNormal cells only NSNormal & Sickle cells SSSickle cells only

23. 2. Incomplete Dominance- neither allele is completely dominant to mask the other. ○ Phenotype: the heterozygote results in a blended phenotype. ○ Genotype: Capital letters for both alleles and use a prime (‘) symbol. ○ Ex: In humans this happens in the genes for curly hair. H= curly, H’= straight. So… GenotypePhenotype H Curly H H’Wavy H’ Straight

24. Ticket Out the Door  If feather color in a species of birds is codominant, cross a white bird with a black and white spotted bird. List all possible phenotypes.  If fur color is incompletely dominant, cross a gray fur dog with a black dog. List all possible phenotypes.

25. Entry 36 10/26  Pick up practice problems on Lab Station 1 complete and paste/tape into journal. (Incomplete/Codominant Probs.)

26. 3. Multiple Alleles: more than two alleles exist for a trait  Blood Types: A, AB, B, O GenotypePhenotype I A I A or I A i A I A I B AB I B I B or I B i B (ii)- recessive O

27. 4. Sex-linked Traits: Are you colorblind??

28. 4. Sex-Linked: trait found on the X sex chromosome. Hemophilia and Color blindness are recessive disorders.  Phenotype: Female – less likely but can express a sex-linked trait Male –express sex-linked traits more often because they have only one X sex chromosomes FemaleMale GenotypePhenotypeGenotypePhenotype X A UnaffectedX A YAffected X A X a CarrierNo male-carriers for a sex linked disorders. XaXaXaXa AffectedXaYXaY Unaffected

29. 5. Polygenetic- Traits that depend on many genes and create a range of phenotypes.  NO PUNNETT SQUARE can be used.  Instead these traits can be graphed using a bell-shaped curve. There is a wide range of differences.  Ex. Height, skin color, weight

30.  You have been given one blood sample to test.  Follow the directions on the sheet to test your sample.  Record your results on your answer sheet.  Record Results on Board- Type of Sample (ex: suspect #1) and your results

31. Ticket Out the Door  1. A sex-linked trait is found on the __ chromosome.  2. Cross a mom with type AB blood with a dad who is type O. List all possible phenotypes.

32. Entry 3710/30  NEW SEATS - Look for your name on the desk  Pick up practice problems on Lab Station 1 complete and paste in journal.

33. Entry 3810/31  Autosomal Trait  Trait inherited on one of the first 22 pairs of chromosomes……. NOT sex-linked  Aneuploidy  Having too many or too few chromosomes  Causes by mistakes in Meiosis--  nondisjunction

34. H. Genetic Disorders 1. Huntington’s disease- found on chromosome 4, causes brain to break down, loss of muscle coordination, and symptoms often appear in your 40’s. Pattern of Inheritance: Autosomal Dominant 2. Sickle-cell Anemia- leads to misshapen red blood cells, leads to poor circulation and pain. Pattern of Inheritance: Autosomal Codominant (both versions of trait are equally dominant) Heterozygous individuals are resistant to malaria Primarily in African-Americans

35. 3. Cystic fibrosis- increased mucus in lungs and digestive tract,. Pattern of Inheritance: Autosomal Recessive Mostly affects Caucasians. 4. Tay-Sach’s disease- breaks down central nervous system leading to premature death (die before 2). Pattern of Inheritance: Autosomal Recessive Found in Jewish and Pennsylvania Dutch populations. 5. PKU (phenylketonuria)- Inability to break down the amino acid phenylalanine, Can build up in brain and lead to decreased mental function Pattern of Inheritance: Autosomal Recessive Can be controlled by diet

36. 6. Hemophilia- blood does not clot normally Pattern of Inheritance: Recessive sex-linked disorder Mainly affects males. Carriers are females only. 7. Colorblindness Pattern of Inheritance: Recessive sex-linked disorder Mainly affects males. Female carriers only.

37. I. Chromosomal Disorders  Inherited due to problems with the ENTIRE chromosome.  Caused by a mistake in MEIOSIS called nondisjunction. Nondisjunction is when chromosomes fail to separate properly. This mistake leads to Aneuploidy- an incorrect (extra or missing) number of chromosomes in a fertilized zygote.

38. Non disjunction causes aneuploidy

39. 1. Down’s Syndrome- is caused by an extra chromosome #21 (trisomy 21). Causes mental retardation, heart defects, and an enlarged tongue.

40. 2. Klinefelter’s Syndrome- male has an extra X-chromosome (XXY). Male but develops female secondary sex characteristics, and usually sterile. Use testosterone therapy to treat. 3. Turner’s Syndrome- female with ONLY one X-chromosome (XO). Female with underdeveloped gonads, infertile.

42. Entry 39 11/1  Identify each disorder as Autosomal Disorder or Chromosomal Disorder The chromosomes fail to separate leading to Down Syndrome The gene that controls red blood cells is found on chromosome pair 11 sickled shaped cells can result causing poor blood circulation. A female only inherits one X chromosome and results in underdeveloped female characteristics

43. J. Nature vs. Nurture:  Nature is heredity (your DNA).  Nurture is your environment  Scientist debate: Which has a greater influence?  Example: We use identical twins to study the effects of the environment on genes.  Diet: can stop the progression of PKU, and limit the risk for genetic predispositions such as diabetes, heart disease, and certain cancers.  Environmental Toxins: environmental factors such as UV radiation or tobacco can directly change our genes (lung/mouth cancer, skin cancer)

44. Ticket out the Door ____Turner’s Syndrome A. Sex Linked Disorder ____Sickle Cell Anemia B. Autosomal Chromosome Disorder ____Colorblindness C. Sex Chromosome Disorder ____Down’s Syndrome D. Autosomal Codominant Disorder How can your environment influence gene expression?