1. Genetics & Heredity Mr. Nigh

2. Who was Gregor Mendel?

3. Who was Gregor Mendel?
Austrian monk who studied mathematics and science
As a boy he could predict the possible types of flowers and fruits that would result from crossbreeding two plants in his father’s garden

4. Who was Gregor Mendel?
Curiosity about the connection between the color of a pea flower and the type of seed that same plant produced inspired him to begin experimenting with garden peas in 1856.
Gregor Mendel made careful use of scientific methods, which resulted in the first recorded study of how traits pass from one generation to the next.

5. What is GENETICS?

6. What is GENETICS?
The study of how traits are inherited through the interactions of genes.

7. What is a GENE?

8. What is a GENE?
The material that controls which traits are expressed in an organism
Genes come in pairs and offspring inherit one copy of each gene from each parent

9. Define the following terms:
Heredity
Allele
Trait

10. The passing of traits from parent to offspring
Define HEREDITY
The passing of traits from parent to offspring

11. Define ALLELE The different forms of a trait that a gene may have
One form of a gene

12. Define TRAIT Ways of looking, thinking, or being
Traits that are genetic are passed down through the genes from parents to offspring

13. Describe RECESSIVE

14. Describe RECESSIVE
A trait that is covers over, or is dominated, by another form of that trait and seems to disappear
Hidden when the other copy of the gene contains the dominant allele.
A recessive allele shows up only when there is no dominant allele present
Shown with a lower-case letter

15. Describe DOMINANT

16. Describe DOMINANT
A trait that covers over, or dominates, another form of that trait
Trait that always shows up, even when only one of the two alleles is in the dominant form
Shown by a capital letter

17. Complete
Dominance

18. Describe INCOMPLETE DOMINANCE

19. Describe INCOMPLETE DOMINANCE
For example:
The gene for the color of some flowers has one allele for red and one for white. When both alleles are present, neither is dominant, and the flower color is pink

20. Incomplete
Dominance

21. Describe CO-DOMINANCE
For example:
The gene for the color of some flowers has one allele for red and one for white. When both alleles are present, neither is dominant, and the flower petals are half white and half red.

22. Co-Dominance

23. Define GENOTYPE

24. Define GENOTYPE
An organism's genetic makeup
Ex.
RR Rr rr

25. Define PHENOTYPE

26. Outward physical appearance and behavior of an organism
Define PHENOTYPE
Outward physical appearance and behavior of an organism
Ex.
Blue flowers, Green Seeds etc.

27. What is HOMOZYGOUS?

28. What is HOMOZYGOUS? Both alleles [forms of the gene] are the same
When offspring inherit two dominant genes, (one dominant gene from each parent) they are said to be homozygous dominant ex. RR
When offspring inherit two recessive genes, (one recessive gene from each parent) they are said to be homozygous recessive ex. rr

29. What is HETEROZYGOUS?

30. What is HETEROZYGOUS? When alleles occur in different forms
When offspring inherit one dominant gene and one recessive gene, they are said to be heterozygous ex. Rr
Since the dominant gene will be expressed, they are said to be heterozygous dominant

31. What is a PUNNETT SQUARE?

32. What is a PUNNETT SQUARE?
A tool to predict the probability of certain traits in offspring that shows the different ways alleles can combine
A way to show phenotype & genotype
A chart that shows all the possible combinations of alleles that can result when genes are crossed

33. What is a PUNNETT SQUARE?
Letters stand for dominant and recessive alleles
An uppercase letter stands for a dominant allele
A lowercase letter stands for recessive alleles

34. Eye Color Punnett Square

35. Read More About Punnett Squares Here:

36. List the 3 Principles of Heredity

37. List the 3 Principles of Heredity
Traits are controlled by alleles on chromosomes
An allele’s effect is dominant or recessive
When a pair of chromosomes separate during meiosis the different alleles for a trait move into separate sex cells

38. What is meant by MULTIPLE ALLELES?

39. What is meant by MULTIPLE ALLELES?
A trait that is controlled by more than two alleles is said to be controlled by multiple alleles
Traits controlled by multiple alleles produce more than three phenotypes of that trait

40. What is meant by MULTIPLE ALLELES?
For Example:
The alleles for blood types in humans are called A, B, and O
The O allele is recessive to both the A and B alleles

41. What is meant by MULTIPLE ALLELES?
When a person inherits one A allele and one B allele for blood type, both alleles are expressed
The person has the blood phenotype AB

42. What is meant by MULTIPLE ALLELES?
A person with phenotype A blood inherited an A and an O allele (AO)
~OR~
an A and an A allele (AA)

43. What is meant by MULTIPLE ALLELES?
Someone with phenotype B blood has the genotype BB or BO
This person inherited either a B and an O allele
~OR~
Two B alleles

44. What is meant by MULTIPLE ALLELES?
A person with phenotype O blood has the genotype OO