1. Types of Chromosomes a. Autosomes
Any chromosome that is not a sex chromosome. 1 to 22
b. Sex Chromosomes
A chromosome involved with determining the sex of an organism. X and Y chromosomes

2. Types of Cells a. Somatic cells
Any cell of a living organism other than the reproductive cells. 
b. Gametes (sex cells)
A reproductive cell having the haploid number of chromosomes. 2

3. Mitosis: Somatic Cell Division
Parent cell
(2n)
Daughter cells
Meiosis:
Gametes
(n)
Offspring 3

4. Mitosis
Somatic Cell Division

5. Science of Inheritance Genes
Alleles:
Different forms of a gene.
Dominant:
If the dominant allele (gene) is present, the organism will show that trait.
Recessive:
Trait will be exhibited only if organism does not have dominant allele or is pure for recessive trait.

6. Science of Inheritance Genes
Genotype:
The Allele combination, heterozygous (hybrid) or homozygous (gg, GG, or Gg).
Phenotype:
The physical characteristic displayed (green or yellow). 6

7. Science of Inheritance Genes
Trait
Dominant Allele
Recessive Allele
Possible
Genotype
Phenotypes
Seed Color
G (green)
g (yellow) GG
Homozygous Gg
Heterozygous gg
Green
Yellow
Flower Color
P (purple)
p (white) PP Pp pp
Purple
white

8. Science of Inheritance Genes
Homozygous: 2 copies of the same alleles (ex. TT and tt)
homozygous dominant- TT
homozygous recessive- tt
Heterozygous: different copies of alleles (ex. Tt)

9. Sex Linked Genes Traits located on the X chromosome
Genotype Phenotype
XCXC Normal Female
XCXc Carrier Female
XcXc Colorblind Female
XCY Normal Male
XcY Colorblind Male
XC Y
Cross: A normal male with a carrier
female. XCY x XCXc
XC XC
Normal Female
XCY
Normal Male
XCXc
Carrier Female
XcY
Colorblind Male XC Xc

10. Sex Linked Genes Traits located on the X chromosome
Genotype Phenotype
XCXC Normal Female
XCXc Carrier Female
XcXc Colorblind Female
XCY Normal Male
XcY Colorblind Male
Xc Y
Cross: A colorblind male with a carrier
female. XCY x XCXc
Xc Xc
Colorblind Female
Xc Y
Normal male
XC Xc
Carrier Female
XC Y
Colorblind Male XC Xc

11. Sex Linked Genes Traits located on the X chromosome
Genotype Phenotype
XCXC Normal Female
XCXc Carrier Female
XcXc Colorblind Female
XCY Normal Male
XcY Colorblind Male
Cross: A normal male with a carrier
female. XCY x XCXc
Cross: A colorblind male with a carrier
female. XCY x XCXc
Xc Y
XC Y
Xc Xc
Colorblind Female
Xc Y
Normal male
XC Xc
Carrier Female
XC Y
Colorblind Male
XC XC
Normal Female
XCY
Normal Male
XCXc
Carrier Female
XcY
Colorblind Male XC Xc XC Xc

13. II. Practice with Punnett Squares- Mendelian Genetics (autosomes!)
homozygous recessive x homozygous dominant
heterozygous x heterozygous
homozygous recessive x heterozygous
homozygous dominant x heterozygous

14. III. Crosses that involve sex-linked (X-linked) genes
“Carrier”-
Examples of X-linked diseases-