1. Complete the human trait inventory
Warm up

2. Wanna see something weird from our knowledge of genetics?
Review of Genetics
Wanna see something weird from our knowledge of genetics?

3. Knowledge of Genetics
Replace This
With This!

4. Eat your vaccine
“Being edible, the vaccines require no syringes- which aside from costing something, can lead to infections if they become contaminated.” Scientific America v16 #4

5. Chromosome Explanation
Inheritance
$ $ $ $ $ $ $
Chromosome Explanation *

6. How can two brown rabbits have a white bunny
How can two brown rabbits have a white bunny? (try to think genetically)

7. Law of Dominance
An organism with a dominant allele for a particular trait will always exhibit that form of the trait.

8. Law of Dominance *

9. Homozygous
Heterozygous
RR rr Rr

10. Law of Segregation
You will only pass on 1 of your two copies of a gene to the next generation. *

11. BY THE WAY…
Phenotype
Genotype *

12. Phenotype
A phenotype is any observable characteristic or trait of an organism
(Looks)

13. Genotype
the actual genetic makeup of an organism
(Letters)

14. Question
Does the gene that determines whether a seed is round or wrinkled in shape have anything to do with the gene for seed color ?

15. Hmm…
I don’t think so… I believe that they are separate
Let’s see what Mendel did to find out

16. Law of Independent Assortment
Mendel crossed pea plants looking specifically for 2 traits…
*Round or wrinkled pea shape
*Yellow or green pea color
R r
Y y

17. Law of Independent Assortment
He crossed plants that he KNEW were heterozygous for these traits…
What were the genotypes/Phenotypes for these plants?

18. Law of Independent Assortment
R r Y y
Genotype =
Phenotype =
Round and Yellow

19. Law of Independent Assortment
So what did he find?
9 Round/Yellow
3 Round/green
3 wrinkled/Yellow
1 wrinkled/green

20. Law of Independent Assortment

21. Back to the Question
So…does the gene that determines whether a seed is round or wrinkled in shape have anything to do with the gene for seed color ?

22. Law of Independent Assortment
No!…Genes for different traits can segregate (“separate”) independently during the formation of gametes
Watch, I’ll show you…press the cheese!

23. Summary of Mendel
The inheritance of biological characteristics is determined by individual units known as genes. Genes are passed on from parents to their offspring.
When two or more forms (a____) of the gene for a single trait exist, some forms may be dominant and others recessive.
Each adult has two copies of each gene- one from each parent. These genes are segregated from each other when gametes (sex cells) are formed.
The alleles for different genes usually separate independently of one another.

24. Cuidado… It’s definitely not always that simple!!

25. Beyond Dominant and Recessive
Alleles can be trickier than wrastlin’ Gators mate!

26. Beyond Dominant and Recessive
Croiky! He’s right! There’s things like Incomplete Dominance …Codominance… and more mate!

27. What’s he talking about
What’s he talking about? I thought the alleles were either Dominant or recessive

28. Different kinds of Dominance
Incomplete Dominance
Codominance
Multiple Alleles
Polygenic traits

29. Incomplete Dominance
In incomplete dominance, the heterozygous phenotype is somewhere in between the two homozygous phenotypes

30. How about an example?

31. Incomplete Dominance
Some Flowers

32. Who lives in a Pineapple under the sea?

33. Now Lets look at Codominance

34. Codominance
In this situation, both alleles contribute to the phenotype (physical characteristics).
In other words, neither allele is dominant.

35. Codominance

36. Here’s an example using CHICKENS!
Codominance
Here’s an example using CHICKENS!

37. Both black & white feathers
At the other extreme from complete dominance is codominance in which two alleles affect the phenotype in separate, distinguishable ways. X
White
Chicken
Black
Checkered
Chicken
Both black & white feathers

38. Multiple Alleles Allele Allele Allele Allele Allele Allele Allele
Many genes have more than two alleles and are therefore said to have “multiple alleles”
Allele
Allele
Allele
Allele
Allele
Allele
Allele
Allele
Allele
Allele

39. Most genes have more than two alleles in a population.
This does not mean that an individual can have more than two alleles!!
It only means that more than two kinds of alleles exist in the entire population!

41. The ABO blood groups in humans are determined by three alleles, IA, IB, and i.

42. I I or I i A B I I A and B AB i i none O
Both the IA and IB alleles are dominant to the i allele.
Genotypes Surface Phenotypes
Molecules
I I or I i
A A A A
B B B B
I I
A B
A and B AB
i i
none O

43. I I or I i A B I I A and B AB i i none O
The IA and IB alleles are codominant to each other.
Genotypes Surface Phenotypes
Molecules
I I or I i
A A A A
B B B B
I I
A B
A and B AB
i i
none O

44. I I or I i A B I I A and B AB i i none O Genotypes Surface Phenotypes
Because each individual carries two alleles, there are six possible genotypes and four possible blood types.
Genotypes Surface Phenotypes
Molecules
I I or I i
A A A A
B B B B
I I
A B
A and B AB
i i
none O

45. I I or I i A B I I A and B AB i i none O Genotypes Surface Phenotypes
Individuals that are IA IA or IA i are type A and place type A oligosaccharides on the surface of their red blood cells.
Genotypes Surface Phenotypes
Molecules
I I or I i
A A A A
B B B B
I I
A B
A and B AB
i i
none O

46. I I or I i A B I I A and B AB i i none O Genotypes Surface Phenotypes
Individuals that are IB IB or IB i are type B and place type B oligosaccharides on the surface of their red blood cells.
Genotypes Surface Phenotypes
Molecules
I I or I i
A A A A
B B B B
I I
A B
A and B AB
i i
none O

47. I I or I i A B I I A and B AB i i none O Genotypes Surface Phenotypes
Individuals that are IA IB are type AB and place both type A and type B oligosaccharides on the surface of their red blood cells.
Genotypes Surface Phenotypes
Molecules
I I or I i
A A A A
B B B B
I I
A B
A and B AB
i i
none O

48. I I or I i A B I I A and B AB i i none O Genotypes Surface Phenotypes
Individuals that are ii are type O and place neither oligosaccharide on the surface of their red blood cells.
Genotypes Surface Phenotypes
Molecules
I I or I i
A A A A
B B B B
I I
A B
A and B AB
i i
none O

50. Matching compatible blood groups is critical for blood transfusions because a person produces antibodies against foreign blood factors.
*If the donor’s blood has an A or B oligosaccharide that is foreign to the recipient, antibodies in the recipient’s blood will bind to the foreign molecules, cause the donated blood cells to clump together, and can kill the recipient.

52. Universal recipient
Universal donor

53. Phenotype depends on environment and genes.
A single tree has leaves that vary in size, shape, and greenness, depending on exposure to wind and sun.

54. For humans, nutrition influences height, exercise alters build, sun-tanning darkens the skin, and experience improves performance on intelligence tests.

55. Even identical twins, genetic equals, accumulate phenotypic differences as a result of their unique experiences.

56. The relative importance of genes and the environment in influencing human characteristics is a very old and hotly contested debate.