1. 11.1 – Intro. To genetics
FQ: What key genetics vocabulary do I need to understand before I can start learning about genetics?
ET: Read the chapter mystery on pg Write down the question that is to be investigated as we go through the chapter.

2. Basic vocabulary to help in our study of genetics
Allele
Fertilization
Principle of dominance
Trait
Segregation
Hybrid
gamete
Gene

3. Vocabulary Gametes: These are sex cells
Ex. Animals have sperm and egg
Ex. Plants have pollen and ovum
Fertilization: in sexual reproduction, this is the joining of gametes
Ex. Sperm and egg form a cell that develops into an embryo

4. Vocabulary
Trait: the physical expression of a gene, basically a characteristic
Gene: the actual information in the DNA that determines traits. This is what is passes from generation to generation
Allele: Different forms of a trait
The trait is height
The different alleles for height could be short or tall
Genetics: the study of heredity – the passing of genetic information from one generation to the next

5. Traits VS. Alleles The trait - eye color The trait - thumb shape
Alleles (forms): blue, brown, green
The trait - thumb shape
Alleles: bent or straight
The trait - hair line
Alleles: widows peak or straight

6. Vocabulary continued…
Segregation: When homologous pairs of chromosomes (one moms and one dads) separate to make gametes (haploid cells)
Principle of Dominance: some alleles are dominant over others

7. Lets look at some of these traits!
Read through the “Quick lab” on pg. 311
Make the data table in your notebook
Make your prediction according to step 2
Figure out your features
Survey your friends!

8. 11.1 - Gregor Mendel Learning Targets: Entry Task:
Describe how Mendel studied inheritance in peas
Summarize Mendel’s conclusions about inheritance
Entry Task:
Trait: fur pattern
Alleles: ????
Pick a trait and list the possible alleles for that trait

9. Gregor Mendel 1822 Who: An Austrian monk
What: developed an explanation for the mechanism of evolution

11. What Mendel did… F2
Generation P
Parental F1
Generation

12. Genotype VS. Phenotype
Phenotype: what form of the trait is expressed – what they look like!
Tall
Short
Blue eyes etc…
What every form of trait you see in that individual
Genotype
Homozygous – an organisms has two identical alleles, like “TT.” Both parents gave a tall allele
Homozygous dominant
Homozygous recessive
Heterozygous – an organisms has two different alleles, like “Tt.” Parents gave different forms of the height gene

13. Lets practice! For each set of alleles, write the genotype and phenotype.
Straight hair is dominant over curly SS Ss ss
Freckles recessive to no-freckles FF Ff ff
Brown fur is dominant over white BB Bb bb

14. 11.2 – Genotypes and Phenotypes
ET: Choose letters and write the alleles for the given genotype
Brown eyes is dominant over blue eye
Homozygous dominant
Heterozygous
Homozygous recessive
Widows peak is dominant over straight hair line
Attached ear lobes is recessive to unattached

15. Mendel’s Conclusions
Inheritance is determined by factors that are passed from one generation to the next, genes.
Some forms of a trait (alleles) are more dominant than others, the principle of dominance

16. Biology – Punnett Squares
LT: Today I will…
Make predictions about patterns of inheritance
Use mathematical methods for solving genetics problems (Punnett square)
ET: Write the genotype for an individual who has attached ear lobes, has a widows peak, and hairy fingers
eeWWFF
eeWwFw

17. Punnett Squares We will cross two homozygous parents
TT – homozygous dominant
tt – homozygous recessive T T t t

18. 11.2/11.3 – Probability and Patterns of Inheritance
LT: Today I will…
Explain the principle of independent assortment
Use Mendel’s principles to solve punnett square problems
ET: What are the possible allele combination in the following individuals gametes
Genotype is TTRR
Genotype is ttrr
Genotype is TtRr

19. Lets practice making gametes!
If the genotype is…
Bbyy
bbYY
BBYy
HHJJII
Hhjjii
HhJjIi
Possible gametes are…
By by bY
BY By
HJI
Hji hji
HJI HjI Hji HJi hJI hji hJi hjI

20. The Two-Factor Cross: 2 traits
P generation: RRYY homozygous dominant for round yellow peas x rryy homozygous recessive for wrinkled green peas
RRYY Parent’s Gametes –
rryy Parent’s Gametes - RY RY RY RY ry ry ry ry

21. Lets cross 2 F1 generation plants!
All the possible combos. RY Ry rY ry
RRYY
RRYy
RrYY
RrYy
RRyy
Rryy
rrYY
rrYy
rryy

22. Other forms of Inheritance
Incomplete Dominance = A blending of both alleles
Ex. The allele for red petals is not completely dominant over the allele for white petals so the offspring has pink petals

23. Continued…
Co-dominance = Both traits will show up. They are not blended together, you actually see both
Ex. The allele for black feathers is co-dominant with the allele for white feathers so the bird is black and white spotted

24. Continued…
Sex linked traits – some inherited traits are located on the chromosomes that determine gender, the X or Y.
Females have two X chromosomes: XX genotype
Males have one of each: XY genotype
EX. Hemophilia is an X-linked recessive disorder. This means…
If you’re a make, XY, and you inherit a recessive allele it will show up because you do not have another X chromosome with a normal dominant allele to over power it.

25. Meiosis Simulation

26. Get your Snurfle worksheet out for reference
Meiosis
Get your Snurfle worksheet out for reference
ET: What is meiosis?
Learning objectives:
Explain the process of meiosis
Compare mitosis and meiosis
Identify crossing over
Explain how linked genes work

27. Independent Assortment
Genes on different chromosomes segregate independently during the formation of gametes (meiosis)

28. Crossing Over

29. Polygenic Traits
Traits controlled by two or more genes: eye and skin color. So there are several different combinations possible
*Incomplete dominance – In a heterozygote there is a blending of the two traits ex. Red and white produce pink
*Co-dominance – In a heterozygote both traits are visible ex. Black and white speckled chickens

30. Focus Question: Epigenetics – does the environment have a role in how genes determine traits?
Make a claim about this