1. Genetics - study of heredity Gregor Mendel is the first
UNIT : Genetics What are the genetics vocabulary words which explain patterns of inheritance?
Heredity – passing of characteristics (traits)from parents to offspring
Genetics - study of heredity
Gregor Mendel is the first
scientist to succeed in predicting
how traits are passed on from
one generation to the next

2. Genetics
- Mendel worked with pea plants and studied only one trait at a time.

3. Genetics He came up with the following laws:
Law of Segregation (separation) states that gene
pairs separate when gametes are formed, so each
gamete (sex cell) has only one allele of each pair

4. Genetics He came up with the following laws:
Law of Independent Assortment states that
different pairs of genes separate independently of
each other when gametes are formed.

5. Important Genetics Vocabulary!!!
Allele – different forms of a trait (remember: genes are found on chromosomes and code for specific traits
Ex: Trait: type of earlobe in humans Alleles: free or attached earlobes
Attached is recessive!= e Free is dominant!=E

6. Important Genetics Vocabulary!!!
Ex: Trait: hair color in humans Alleles:
brown, blonde, red, black, etc…

7. Genetics Vocabulary
- Alleles are represented by letters when you’re predicting the probability of traits to be passed down to your offspring.
B=brown eyes
b=blue eyes

8. Genetics Vocabulary Dominant – allele that is visible
- represented by a capital letter
B=Brown eyes
Recessive – allele that is “hidden”;
it is “masked” by the dominant allele
represented by a lowercase letter
b=Blue eyes

9. Genetics Vocabulary
Homozygous - 2 identical or same alleles for a trait
a.k.a. Pure or purebred
BB=homozygous dominant
bb=homozygous recessive
Heterozygous different alleles
for a trait
a.k.a. hybrid
Bb=heterozygous

10. Genetics Vocabulary Phenotype – the physical appearance of an organism
- what the organism looks like
- represented by words/descriptions
Ex. I have BLUE eyes!
Genotype – the genes that an organism has
- the genetic makeup –what
genes make up the organism
represented by letters
Ex. I have the genes=bb