1. Genetics – The study of Inheritance
Chapter 20 : Section 2 -
Genetics – The study of Inheritance

2. Heredity
When traits are passed from parent to offspring

3. Genetics
The study of how traits are passed from parent to offspring

4. Genes
Traits are inherited
How about manners?

5. Genes Small section of DNA on a chromosome (there are thousands)
Contains info about a trait

6. Alleles Remember chromosomes come in pairs (How many pairs?)
Genes come in pairs too – one on each chromosome

7. Dominant and Recessive alleles
Combination of alleles determines the trait
Pea plants can have purple or white flowers
Pea Plant

8. Dominant and Recessive alleles
Purple allele is dominant
White allele is recessive P p

9. Dominant and Recessive alleles
If a baby plant gets a Purple allele from one parent and a Purple allele from the other parent what color will the flowers be? P P

10. Dominant and Recessive alleles
If a baby plant gets a Purple allele from one parent and a White allele from the other parent what color will the flowers be? p P

11. Dominant and Recessive alleles
If a baby plant gets a white allele from one parent and a white allele from the other parent what color will the flowers be? p p

12. VAriation
Different ways a trait appears
Can be small or large

13. Mutation A change in a gene or chromosome Can be good Can be neutral
Can be bad

14. Selective Breeding
Take those good mutations and control them

15. Bill Nye Review Clip