1. Genetics & Heredity

2. Who was Gregor Mendel?
Austrian monk who studied mathematics and science
Between Mendel made careful use of scientific methods, which resulted in the first recorded study of how traits pass from one generation to the next.

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

4. 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

5. The passing of traits from parent to offspring
Define HEREDITY
The passing of traits from parent to offspring
Define ALLELE
The different forms of a trait that a gene may have. One form of a gene
Define TRAIT
Ways of looking, thinking, or being.
Traits that are genetic are passed down through the genes from parents to offspring

6. Describe RECESSIVE
A trait that is covered over, or 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

7. 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

8. 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
When offspring inherit two recessive genes, (one recessive gene from each parent) they are said to be homozygous recessive

9. 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
Since the dominant gene will be expressed, they are said to be heterozygous dominant

10. Define GENOTYPE
An organism's genetic makeup

11. Outward physical appearance and behavior of an organism
Define PHENOTYPE
Outward physical appearance and behavior of an organism

12. What is a PUNNETT SQUARE?
A tool to predict the probability of certain traits in offspring that shows the different ways alleles can combine.
Letters stand for dominant and recessive alleles
An uppercase letter stands for a dominant allele
Lowercase letters stand for recessive alleles

13. Monohybrid Cross r r Rr Rr R R Rr Rr Trait: Seed Shape
Mendelian Genetics
4/16/2017
Monohybrid Cross
A breeding experiment that tracks the inheritance of one traits.
Trait: Seed Shape
Alleles: R – Round r – Wrinkled
Cross: Round seeds x Wrinkled seeds
RR x rr
Genotype: Rr
Phenotype: Round
Genotypic Ratio: All alike
Phenotypic Ratio: All alike r r Rr Rr R R Rr Rr

14. Dihybrid Cross RY Ry rY ry RRYY RRYy RrYY RrYy RRyy Rryy rrYY rrYy
Mendelian Genetics
4/16/2017
Dihybrid Cross
A breeding experiment that tracks the inheritance of two traits. RY Ry rY ry
Round/Yellow: 9
Round/green: 3
wrinkled/Yellow: 3
wrinkled/green: 1
9:3:3:1 phenotypic ratio
RRYY
RRYy
RrYY
RrYy
RRyy
Rryy
rrYY
rrYy
rryy

15. Mendelian Genetics
4/16/2017
Generation “Gap”
Parental P1 Generation = the parental generation in a breeding experiment.
F1 generation = the first-generation offspring in a breeding experiment. (1st filial generation)
From breeding individuals from the P1 generation
F2 generation = the second-generation offspring in a breeding experiment. (2nd filial generation)
From breeding individuals from the F1 generation

16. Describe Co-Dominance and Incomplete Dominance
Incomplete Dominance when both alleles are present, neither is dominant, and the flower color is pink due to the blending of colors.
Co-Dominance is when two alleles are expressed and one does not mask the other.

17. 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

18. Mendelian Genetics
4/16/2017
Law of Segregation
During the formation of gametes (eggs or sperm), the two alleles responsible for a trait separate from each other.
Alleles for a trait are then "recombined" at fertilization, producing the genotype for the traits of the offspring.

19. Law of Independent Assortment
Mendelian Genetics
4/16/2017
Law of Independent Assortment
Alleles for different traits are distributed to sex cells (& offspring) independently of one another.
This law can be illustrated using dihybrid crosses.

20. 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
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

21. What is POLYGENIC INHERITANCE?
Occurs when a group of gene pairs acts together to produce a trait
The effects of many alleles produces a wide variety of phenotypes

22. What is a Karyotype
The characterization of the chromosomal complement of an individual or a species, including number, form, and size of the chromosomes.

23. What is a pedigree chart?
Pedigree charts show a record of the family of an individual
They can be used to study the transmission of a hereditary condition
They are particularly useful when there are large families and a good family record over several generations.

24. Symbols used in pedigree charts
A marriage with five children, two daughters and three sons. The eldest son is affected by the condition.
Eldest child  Youngest child
Normal male
Affected male
Normal female
Affected female
Marriage

25. Organizing the pedigree chart
Generations are identified by Roman numerals I II
III IV

26. DNA Fingerprinting
DNA Fingerprinting is a procedure whereby the genetic information, called DNA, in a person's cells is analyzed and identified. The word fingerprinting is used because, just like a fingerprint, no two person's genetic code is exactly the same. It can be used to:
Determine Family Relationship - DNA can help find out who a person's parents or siblings are. Prenatal paternity tests are available to mothers who need to identify the father of their unborn babies.
Detect Inherited Diseases - Your genetic code can be tested to determine your likelihood of getting certain diseases.
Prove Guilt or Innocence - DNA left at the scene of a crime can be matched with a sample from a suspect.
Identify a Dead Body - The DNA from an unidentified body can be matched with a person in a government DNA database.

27. Sample Of A DNA Fingerprint