Download - Genetics Intro
![Page 1: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/1.jpg)
GeneticsA study of inheritance
![Page 2: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/2.jpg)
ObjectivesA.Understand1.Phenotype2.Genotype3.Dominance4.Gene Segregation
B.Use a Punnett square to1.Solve monohybrid crosses2.Predict genotype ratio3.Predict phenotype ratio
![Page 3: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/3.jpg)
Gregor Mendel
• Father of modern genetics
![Page 4: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/4.jpg)
Gregor Mendel
• Father of modern genetics
• Researched with pea plants
![Page 5: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/5.jpg)
Gregor Mendel
• Father of modern genetics
• Researched with pea plants
• Developed ideas of dominance and trait segregation
![Page 6: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/6.jpg)
Phenotype
• Phenotype – Physical characteristics
![Page 7: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/7.jpg)
Genotype
• Phenotype – Physical characteristics
• Genotype – Genes we inherit from our parents
![Page 8: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/8.jpg)
Phenotype
– Facial structure
Notice the similarities:
![Page 9: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/9.jpg)
Phenotype
– Facial structure– Eyes
Notice the similarities:
![Page 10: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/10.jpg)
Phenotype
– Facial structure– Eyes– Smile
Notice the similarities:
![Page 11: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/11.jpg)
Phenotype
– Facial structure– Eyes– Smile– Ears
Notice the similarities:
![Page 12: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/12.jpg)
Phenotype
– Facial structure– Eyes– Smile– Ears– Nose
Notice the similarities:
![Page 13: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/13.jpg)
Phenotype
– Facial structure– Eyes– Smile– Ears– Nose– Neck
Notice the similarities:
![Page 14: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/14.jpg)
Mendelian GeneticsMendel studied a number of characteristics in pea plants including:
•Height - short or TALL
![Page 15: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/15.jpg)
Mendelian GeneticsMendel studied a number of characteristics in pea plants including:
•Height - short or TALL•Seed color - green or YELLOW
![Page 16: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/16.jpg)
Mendelian GeneticsMendel studied a number of characteristics in pea plants including:
•Height - short or TALL•Seed color - green or YELLOW•Seed shape - wrinkled or ROUND
![Page 17: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/17.jpg)
Mendelian GeneticsMendel studied a number of characteristics in pea plants including:
•Height - short or TALL•Seed color - green or YELLOW•Seed shape - wrinkled or ROUND•Seed coat color - white or GRAY
![Page 18: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/18.jpg)
Mendelian GeneticsMendel studied a number of characteristics in pea plants including:
•Height - short or TALL•Seed color - green or YELLOW•Seed shape - wrinkled or ROUND•Seed coat color - white or GRAY •Pod shape - constricted or SMOOTH
![Page 19: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/19.jpg)
Mendelian GeneticsMendel studied a number of characteristics in pea plants including:
•Height - short or TALL•Seed color - green or YELLOW•Seed shape - wrinkled or ROUND•Seed coat color - white or GRAY •Pod shape - constricted or SMOOTH•Pod color - yellow or GREEN
![Page 20: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/20.jpg)
Mendelian GeneticsMendel studied a number of characteristics in pea plants including:
•Height - short or TALL•Seed color - green or YELLOW•Seed shape - wrinkled or ROUND•Seed coat color - white or GRAY •Pod shape - constricted or SMOOTH•Pod color - yellow or GREEN•Flower position - terminal or AXIAL
![Page 21: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/21.jpg)
Mendelian GeneticsWe will work with the following three:
•Height - short or TALL•Seed color - green or YELLOW•Seed shape - wrinkled or ROUND•Seed coat color - white or GRAY •Pod shape - constricted or SMOOTH•Pod color - yellow or GREEN•Flower position - terminal or AXIAL
![Page 22: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/22.jpg)
Predicting Inheritance
To determine the chances of inheriting a given trait, scientists use Punnett squares and symbols to represent the genes.
UPPERCASE letters are used to represent dominant genes.
lowercase letters are used to represent recessive genes.
![Page 23: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/23.jpg)
Predicting Inheritance
For example:T = represents the gene for TALL in pea plantst = represents the gene for short in pea plants
So:TT & Tt both result in a TALL plant, because T is dominant over t. t is recessive. tt will result in a short plant.
Remember there are two genes for every trait! One from each parent.
![Page 24: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/24.jpg)
Predicting Inheritance
For example:T = represents the gene for TALL in pea plantst = represents the gene for short in pea plants
So:TT & Tt both result in a TALL plant, because T is dominant over t. t is recessive. tt will result in a short plant.
Remember there are two genes for every trait!
Mendels’ Principle of Dominance
Some genes (alleles) are dominant and others are recessive. The phenotype (trait) of a dominant gene will be seen when it is paired with a recessive gene.
![Page 25: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/25.jpg)
Predicting Inheritance
Let’s cross a totally dominant tall plant (TT) with a short plant (tt).Each plant will give only one of its’ two genes to the offspring or F1 generation.
TT x tt
T T t t
![Page 26: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/26.jpg)
Predicting Inheritance
Let’s cross a totally dominant tall plant (TT) with a short plant (tt).Each plant will give only one of its’ two genes to the offspring or F1 generation.
TT x tt
T T t t
Mendels’ “Law” of Segregation
Each gene (allele) separates from the other so that the offspring get only one gene from each parent for a given trait.
![Page 27: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/27.jpg)
Punnett Squares
Tt Tt
Tt Tt
The genes from one parent go here.
The genes from the other parent go here.
![Page 28: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/28.jpg)
Punnett Squares
T T
t Tt Tt
t Tt Tt
![Page 29: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/29.jpg)
Punnett Squares
T T
t Tt Tt
t Tt Tt
![Page 30: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/30.jpg)
Punnett Squares
T T
t Tt Tt
t Tt Tt
![Page 31: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/31.jpg)
Punnett Squares
T T
t Tt Tt
t Tt Tt
![Page 32: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/32.jpg)
Punnett Squares
T T
t Tt Tt
t Tt Tt
![Page 33: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/33.jpg)
Punnett Squares
T T
t Tt Tt
t Tt Tt
F1 generation
![Page 34: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/34.jpg)
Interpreting the Results
The genotype for all the offspring is Tt.The genotype ratio is:
Tt - 4/4
The phenotype for all the offspring is tall.The phenotype ratio is:
tall - 4/4
![Page 35: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/35.jpg)
Punnett Squares
T t
T ?? ??
t ?? ??
Your Turn!!
![Page 36: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/36.jpg)
Punnett Squares
T t
T TT Tt
t Tt ttF2 generation
![Page 37: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/37.jpg)
Punnett Squares
T t
T TT Tt
t Tt tt
Next, give the genotype and phenotype ratios of the offspring (F2 generation).
![Page 38: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/38.jpg)
Punnett Squares
T t
T TT Tt
t Tt tt
Genotype ratio: TT - 1
![Page 39: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/39.jpg)
Punnett Squares
T t
T TT Tt
t Tt tt
Genotype ratio: TT - 1, Tt - 2
![Page 40: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/40.jpg)
Punnett Squares
T t
T TT Tt
t Tt tt
Genotype ratio: TT - 1, Tt - 2, tt - 1
![Page 41: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/41.jpg)
Punnett Squares
T t
T TT Tt
t Tt tt
Genotype ratio: TT - 1, Tt - 2, tt - 1
Phenotype ratio: Tall - 3
![Page 42: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/42.jpg)
Punnett Squares
T t
T TT Tt
t Tt tt
Genotype ratio: TT - 1, Tt - 2, tt - 1
Phenotype ratio: Tall - 3, short - 1
![Page 43: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/43.jpg)
Punnett Squares
T t
T TT Tt
t Tt tt
This is a monohybrid cross. We worked with only one trait. The height of the plant.
![Page 44: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/44.jpg)
Punnett Squares
T t
T TT Tt
t Tt tt
This is a monohybrid cross. We worked with only one trait. The height of the plant.
Later we will work with a dihybrid cross, using the height of the plant and either seed color or seed shape.
two
![Page 45: Genetics Intro](https://reader030.vdocuments.mx/reader030/viewer/2022012910/5481d935b4af9f99108b4e6e/html5/thumbnails/45.jpg)
Homework - Punnett Squares
T t
T TT Tt
t Tt tt
Questions 1 & 2 on Rats Practice Problems and question 1 on Foxes and Watermelons Practice Problems.