2. Gregor Mendel : Known as “THE FATHER OF GENETICS”. - laid the foundations for the SCIENCE OF GENETICS through his study of inheritance patterns of traits in pea plants.

3.  Mendel’s Experiments: He prevented self-pollination and used another method called Cross Pollination (the joining of pollen and egg) from 2 different plants creating what is called a Hybrid (an organism that received 2 different forms of a genetic trait from each parent).

4.  What is a TRAIT? A specific characteristic that can be passed from parent to offspring. What is GENETICS: The study of heredity or inheritance of traits. What is HEREDITY (inheritance)? Passing of traits from parent to offspring or from one generation to the next. Genes are the coded instructions that define our traits

5.   Humans have 2 sets of chromosomes for a total of 46 chromosomes. Each parent contributes only 1 set of chromosomes to their child.  When a sperm cell (23 chromosomes) and an egg cell (23 chromosomes) join during fertilization, it results in a zygote (46 chromosomes). How are genes inherited?

6. The Principle of Dominance: States that some traits are dominate and others are recessive. So what does this mean?

7. A dominant trait is a trait that is visible & expressed using a capital letter ( B ). A recessive trait is a trait that is sometimes “hidden” & is expressed using a lower case letter ( b ) Red eyes are dominant over white eyes in fruit flies.

8. Tongue rolling is dominant over non-rollers (recessive) Widow’s Peak Hairline is dominant over Straight Hairline Cleft Chin is dominant over Smooth Chin

9. PRINCIPLE OF SEGREGATION: States that each pair of genes segregate or separate during meiosis carrying only a single copy of each gene.

10.   Gene: section of chromosome that codes for a protein which will indicate a genetic trait (ex. height of plant or pea pod color).  Most organisms have 2 copies of every gene (on each chromosome).  Alleles: A different form of the same gene (ex. Tall plant vs short plant, yellow pea pod vs green pea pod) IMPORTANT VOCABULARY:

11. HOMOZYGOUS - organisms that have 2 identical alleles for a particular trait and are called true- breeds (purebred). (Genotype would read as HH or hh) HETEROZYGOUS - organisms have 2 different alleles for the same trait and are called hybrids. (Genotype would read Hh)

12. PHENOTYPE – Refers to the physical appearance of an organism. (Tall or short, yellow or green, short tail or long tail) GENOTYPE – Refers to the genetic make up of an organism. (Tt, Ss)

13. PRINCIPLE OF PROBABILITY Method used to predict the possible outcome of genetic crosses (like flipping a coin – you have a 50/50 chance of heads or tails)

14.   A tool or grid used to predict and compare the genetic variations that will result in a cross of two organisms traits. What is a Punnett Square (aka Monohybrid Cross)?

15. Punnett Squares homozygous recessive heterozygous Genotypes Rr - 50% rr - 50% Phenotypes Red - 50% Blonde - 50% RED HEADS ( r ) vs BLONDES (R)

16. Dihybrid Cross (2 factors): a 16 square grid that is used to predict and compare the genetic variations that will result when crossing 2 traits of two organisms. RRYY RRYy RY Ry rY ry RY Ry rY ry RrYY RRYyRRyy RrYy Rryy RrYy RrYY RrYy rrYYrrYy RrYyRryyrrYyrryy

17. PRINCIPAL OF INDEPENDENT ASSORTMENT A random distribution of alleles that occurs during gamete formation (meiosis). The genes on separate chromosomes sort independently during meiosis.