Presentation is loading. Please wait.

Presentation is loading. Please wait.

Chapter 4: Heredity Section1- Genetics Life Science Lesson Plan.

Similar presentations


Presentation on theme: "Chapter 4: Heredity Section1- Genetics Life Science Lesson Plan."— Presentation transcript:

1 Chapter 4: Heredity Section1- Genetics Life Science Lesson Plan

2 Inheriting Traits  Create a short list of characteristics about yourself…  What is another name for these characteristics?  TRAITS

3 Heredity  Heredity is the passing of traits from parents to offspring.  Inherited Traits- Traits that are passed from parents to their offspring (through fertilization)

4 Genes are passed… but what are genes?  Genes are sections of DNA on a chromosome.  These genes on chromosomes control the traits that show up in an organism. –There are thousands of genes on a chromosome

5  Alleles are different forms of a trait that a gene may contain. –There are 2 alleles for each gene –1 from mom and 1 from dad  Example: Height –1 allele is tall –1 allele is small

6 Alleles alleles a gene

7 B. Genetics- is the study of inherited traits. 1. Gregor Mendel- The Father of Genetics “The Man”

8

9 Mendel’s Experiment  Mendel studied the traits of Pea Plants –Look Page 105  Crossed 2 Plants with different expressions of the trait –Example- Tall (T)& Short (t) –Round R & Wrinkled r

10 Mendel’s Experiment  When the plants were crossed he discovered that the new plant formed looked like one of the two parents.  Take a look… Mendel’s Tall vs. Short Plants

11 VOCABULARY  3. Purebreds- offspring receives the two same alleles for a trait (TT or tt)

12 VOCABULARY  4. Hybrids- offspring receives two different alleles for a trait (Tt)

13 2 Types of Alleles a.Dominant allele- covers up or dominates the other trait Represented by a Capital Letter b. Recessive allele- the trait seems to disappear Represented by a lower-case letter

14  “Homo”zygous – an organism with 2 alleles for one trait that are the same (written TT)  “Hetero”zygous – an organism with 2 alleles for one trait that are different (written Tt)

15  Genotype- the genetic- makeup of an organism (types of letters used)

16  Phenotype- the way an organism physically looks/behaves as a result of its genotype.  Types of Words used: Tall, Short, Blonde, Brown, etc.

17 The Use of Punnett Squares  A Punnett Square can help you predict what an offspring will look like. “What’s the Probability of the baby’s gender?”

18  A Punnett Square can help you predict what an offspring will look like 1. Monohybrid: Offspring of parents that differ in only one genetic characteristic

19 Monohybrid Cross: GG x gg

20 DYHIBRID CROSSES 2. Dyhybrid: Offspring of parents that differ in TWO genetic characteristic ***USE FOIL to separate the combinations F – FIRST O – OUTSIDE I – INSIDE L – LAST

21 DIHYBRID EXAMPLE Tall & Green TtGg x TtGg

22 DIHYBRID EXAMPLE #2 Brown hair vs Blonde hair AaBb x aaBb

23

24 Chapter 4 Part 2- Genetics Since Mendel Life Science

25 Question…  If you crossed Purebred Red four- o’clock flower with Purebred White four-o’clock flower, what would the offspring look like?

26  Actually… they were PINK!?!?!

27  Incomplete Dominance- when two homozygous parents combine, the offspring results in a blended phenotype  Combining Purebred Red & White and produced Pink

28  Neither allele for a trait is Dominant.  The phenotype produced is mixed between the two homozygous parents. –The combining of Purebred Red & Purebred White produced PINK plants.

29 What would happen if you crossed a Red horse and a White horse?

30 PINK!?!?!

31 Just kidding… ROAN

32  Although Mendel studied peas that were controlled by two alleles, many traits can be controlled by more than two alleles…

33 Multiple Alleles  A trait that is controlled by Having more than two alleles is controlled by Multiple Alleles.  Traits controlled by Multiple Alleles produce more than three phenotypes of that trait.

34 Example (Flip to Page)  Example of Multiple Alleles…  Blood Types: A, B, AB, and O. –The O allele is recessive to both A and B

35 Other Worksheet…  Phenotype A - AA or AO Genotype  Phenotype B – BB or BO Genotype  Phenotype AB – AB Genotype  Phenotype O – OO Genotype

36

37 Polygenic Inheritance  Polygenic Inheritance- when a group of gene pairs acts together to produce one trait. –Which creates more variety in phenotypes

38 What would be an example?  Many traits such as…Skin Color, Eye Color, Hair Color, and Handspan are traits produced by a combination of genes.

39 Human Genes & Mutations  Mutations : a permanent change in the DNA sequence  A mutation can be helpful, harmful, or cause no effect.

40

41

42

43

44

45

46

47

48

49 Mutations  Chromosome disorders- caused by more or fewer chromosomes than normal  Downs Syndrome- caused by an extra copy of chromosome 21

50 Recessive Genetic Disorders  There are human genetic disorders that are caused by Recessive Genes.  How could this occur?  Both parents contain the recessive allele

51  Because parents are Heterozygous, they do not show any symptoms –(Called “carriers” for the trait.)  Cystic Fibrosis is a homozygous recessive disorder.

52 Sex-Linked Disorders  An allele inherited on a sex chromosomes ( X or Y ) is called a sex-linked gene.  Inherited conditions are linked with the X and Y chromosomes.

53  Example- Color Blindness is a sex- linked disorder caused by recessive allele on the X chromosome.

54

55

56 Where did you get your genes from?

57 Pedigrees  Pedigree- used to follow or trace traits through generations of a family.

58 No… not the dog food…

59 Section 3 III. Advances in Genetics A. Genetic Engineering- experimentations that changes the arrangement of DNA that makes up a gene.

60 Types: 1. Recombinant DNA  Inserting a useful section of DNA into a bacteria  Example- Creating Insulin (Page 143)

61 2. Gene Therapy-  When a “normal allele” is placed into a virus, the virus then delivers the normal allele when it infects a specific cell. (Figure 13 Page 144)  May be used to control Cystic Fibrosis and other disorders.

62 3. Genetically Engineering Plants-  Plants are created by genetically inserting the desired genes of one plant into another plant you want to show those genes.  Also genetically engineered: ANIMALS  “Cloning”

63 Works Cited  www.coolclips.com www.coolclips.com  http://kentsimmons.uwinnipeg.ca/cm15 04/mendel.htm http://kentsimmons.uwinnipeg.ca/cm15 04/mendel.htm  www.classzone.com www.classzone.com  www.dkimages.com www.dkimages.com  www.virtualsciencefair.org www.virtualsciencefair.org  www.scienceray.com


Download ppt "Chapter 4: Heredity Section1- Genetics Life Science Lesson Plan."

Similar presentations


Ads by Google