1. What is Heredity?
_____________- is the Study OF Genes/Heredity

2. Chromosome Review Humans have 46  23 pairs
Each pair consists of one chromosome from mom & one from dad
Types of Chromosomes
Sex chromosomes - 23rd pair
____________

3. __________
Sex Chromosomes

4. Genes & Alleles
Gene – sequence of DNA coding for a protein  determines a trait    
_________– alternate/different forms of a gene
Example: Height = Tall or short      

5. Who was Gregor Mendel? The Father Of Modern__________
Used pea plants to study the inheritance of ________

6. Mendel’s Discoveries:
_____________Alleles - same 2 alleles
_________Alleles - 2 different alleles

7. Dominant Allele – always________
Recessive Allele - only expressed if homozygous _________

8. Principle of _________– some alleles are dominant and others are__________
Phenotype - physical expression/characteristics of the gene
__________– genetic makeup of an organism

9. Mendelian Laws:
Law of ___________– each individual carries a pair of alleles for each trait and these alleles will separate to form gametes
Law of Independent ___________- each trait will separate independently of all other traits.

10. Punnett Squares

11. Punnett Squares Show possible gene combinations – hybrids
Principle of_______________

12. How to use: _____________Cross = Aa x Aa A = Freckles a = No Freckles
Genotype ratio: 1:2:1
AA = 1
Aa = 2
aa = 1
Phenotype ratio: 3:1
With freckles = 3
No freckles = 1

13. Column & Row Letters
They represent _________from one of the parents

14. Dihybrid Cross: RrYy x RrYy
R = Smooth r = Wrinkled Y = Yellow y = Green
Use the _________method (first, outer, inner, last) to produce gamete combinations
Female: RrYy Male: RrYy
Gametes Gametes
RY RY
Ry Ry
rY rY
ry ry

15. _____________Cross Phenotype ratio: 9:3:3:1 Smooth & Yellow = 9
Wrinkled & Yellow = 3
Smooth & Green = 3
Wrinkled & Green = 1