1. Genetics

2. Heredity
Heredity – characteristics inherited from parents to offspring through genes

3. Genetics
The study of genes and heredity

4. Traits
Characteristics that are inherited through genes

5. Gregor Mendel
A monk in the 1800s
First to identify heredity

6. Garden Peas Studied the traits in garden peas Tall/short
Round/wrinkled
Green/yellow pods
Purple/white flowers

7. Background information
Each trait or characteristic has 2 copies of DNA that code for that trait
Each copy of the trait is called an allele
Each organism has two copies of each allele

8. Conclusions Mendel had certain rules for heredity
Characteristic, unit factor/gene/height
Two contrasting traits/alleles/tall or short
Another example pod color – green/yellow

10. The Rule of Dominance
Alleles can be either dominant or recessive (strong or weak)
Dominant alleles are observable
Recessive alleles are not usually observable, when the dominant allele is present

11. The Law of Segregation
Alleles for a gene separate when forming a sperm and egg

12. Law of Independent assortment
Alleles for different genes are distributed to sperm and egg independently
Could be
tall and fat
Short and thin
Tall and thin
Short and fat
Why all siblings do not look exactly alike

13. Dominant The allele that is expressed – you can see it
Use the first letter of the word and capitalize it
C curly hair
B brown hair

14. Recessive The allele that is not expressed
It is covered up by the dominant allele
It is there you just cannot see it
Use the lower case for the recessive allele
c for straight hair
b blonde hair

15. Phenotype
The way an organism physically looks
Brown hair, tall

16. Genotype The copies of alleles or genes that an organism has
Genetic make-up
genotype controls the phenotype
BB, Bb, bb

17. Homozygous – (Homo: same)
Pure
When an organism has 2 copies of the same allele
BB – homozygous dominant
bb – homozygous recessive

18. Heterozygous (Hetero: different)
Hybrid
When an organism has 2 different alleles for a gene
one capital;
one lower case
Bb, Gg etc.

19. Parent or “P” Generation
The 2 organisms that are used to reproduce

20. F1 Generation
The offspring - babies

21. F2 generation
The babies of the F1 or the grandchildren of the P generation

22. Incomplete dominance There is no dominant allele or recessive allele
The 2 alleles are blended
and make up a new physical appearance
Ex. A red allele and a white allele can make a pink flower

23. Co dominance
There is no dominant or recessive allele but both are expressed
Ex: a chicken with white
& black feathers
Blood Types:
A, B, AB, or O

25. Punnett Square
A chart used to predict the probability of traits represented among offspring
If 2 plants pollinate – predict what it would look like!

26. Monohybrid
One cross because you are looking at only one trait

28. Pedigree A diagram representing a family tree
The alleles that each person in the family has

29. Monohybrid Punnett Square Problems
Height – tall is dominant to short
Symbol for tall _______
Symbol for short _____
Phenotype –
Homozygous tall male X short female
Genotype
Male _____ X Female ______

30. P1 Punnett Square
F1 genotype ratio
F1 phenotype ratio

31. Monohybrid Punnett Square Problems
Height – tall is dominant to short
Symbol for tall _______
Symbol for short _____
Phenotype –
_______ male X _______ female
Genotype
Male _____ X Female ______

32. F1 Punnett Square
F2 genotype ratio
F2 phenotype ratio

33. Dihybrid
Two crosses - you are looking at 2 traits

34. Dihybrid Cross
Involves two characteristics (two pairs of contrasting traits) for each individual.
Predicting the results of a dihybrid cross is more complicated than predicting the results of a monohybrid cross.
All possible combinations of the four alleles from each parent must be considered.

35. Dihybrid Cross Example
Purple (P) is dominate to white (p)
Smooth texture (S) is dominant to wrinkled (s)

36. Human Blood Type
There are three different alleles for human blood type.
Each of us has two ABO blood type alleles, because we each inherit one blood type allele from our biological mother and one from our biological father.
Blood Types
Simplified IA A IB B i O

37. Each blood group is represented by a substance on the surface of red blood cells (RBCs). These substances are important because they contain specific sequences of amino acids and carbohydrates which are antigenic.

38. More Info…
Allele from Parent 1
Allele from Parent 2
Geno-type
Blood Type A AA B AB O AO BB BO OO
Since there are three different alleles, there are a total of six different genotypes at the human ABO genetic locus.

39. Blood Types A & B Blood Types Possible Genotypes A AA AO B BB BO
If someone has blood type A, they must have at least one copy of the A allele, but they could have two copies. Their genotype is either AA or AO. Similarly, someone who is blood type B could have a genotype of either BB or BO.
Blood Types
Possible Genotypes A AA AO B BB BO

40. Blood Type AB & O Blood Type Genotype AB O OO
A blood test of either type AB or type O is more informative. Someone with blood type AB must have both the A and B alleles. The genotype must be AB. Someone with blood type O has neither the A nor the B allele. The genotype must be OO.
Blood Type
Genotype AB O OO

41. Rh Factor Rh Factor Possible Genotypes Rh+ Rh+/Rh+ Rh+/Rh- Rh- Rh-/Rh-
There are 2 different alleles for the Rh factor known as Rh+ and Rh-.
Someone who is "Rh positive" or "Rh+" has at least one Rh+ allele, but could have two. Their genotype could be either Rh+/Rh+ or Rh+/Rh-. Someone who Rh- has a genotype of Rh-/Rh-.
Rh Factor
Possible Genotypes
Rh+
Rh+/Rh+
Rh+/Rh-
Rh-
Rh-/Rh-

42. Blood Transfusions
When a blood transfusion is necessary, donor and patient blood must be compatible. If not, the patient’s body will react to the incompatible donor cells, leading to complications, maybe even death.
U.S. percentage of the population shares your ABO grouping.
O+ 37% O- 6%
A+ 34% A- 6%
B+ 10% B- 2%
AB+ 4% AB- 1%