**An Austrian monk who was the first person to observe different inherited traits such as color and height using the reproduction of pea plants I’m a monk and I like peas, darn it !

**In plants, fertilization is called pollination (pollen from the male meets the female parts)  Self-pollination occurs when a plant is allowed to pollinate itself  Cross pollination – Different plants

Male Produces Pollen Female excepts the pollen

**He studied only one trait at a time to control the variables ** He called these traits factors

He would cross-pollinate plants with two variations of one trait: For example, this dwarf plant was mated with this tall plant

P1  Parent Generation **tall plant mated with a short plant Their Offspring (F1)  Filial 1 (1 st generation) **All Tall – allowed to self- pollinate Their offspring (F2) – Filial 2 (2 nd ) generation **3 tall and 1 short

F1 Must carry the tall AND the short “factors”

** Traits are inherited from generation to generation ** Also, a hybrid is the offspring that inherited both the tall “factor” and the short “factor”

~ Rule of Unit factors : Two factors (one from each parent) affect one trait in an individual ~ Rule of Dominance: The observed trait is called dominant and the trait that cannot be seen is recessive

~ We now call Mendel’s factors genes and are found on chromosomes ~ Remember!!! We have a total of46 chromosomes ½ from mom and ½ from dad ~ 44 are called autosomal chromosomes and 2 are called sex chromosomes (X’s and Y’s)

** We call the alternate forms of a gene alleles ** Alleles inherited from the mother are in red. Those inherited from the father in blue. “A” Alleles aA are different, or alternate, forms of the “A” gene D Alleles T Alleles Homologues; Same chromosome from each parent; Just different forms of alleles

 Genotype  pair of alleles denoted by letters › TT = homozygous dominant (Upper Case) › Tt = heterozygous (hybrid, carrier…the recessive “t” is not expressed; the “T” dominnates over the “t”; the “t” cannot be seen › tt = homozygous recessive  Phenotype  how the alleles are expressed; what it “looks” like; such as tall and short or even a genetic disease or abnormality (like polydactyl fingers)

BB Homozygous Dominant bb Homozygous Recessive Remember!! Combination of alleles denoted by using a capital letter for dominant alleles and lower case letters for recessive traits

Genotype (AA, Aa,aa) Codes For Phenotype (Fur Color)

Principle of Segregation: What it means: each gene has two copies (alleles) and a parent will give only one copy to a child. The other parent will give another copy, and thus the child will receive two copies (alleles) Segregation of alleles in the production of sex cells

Principle Independent Assortment : Genes for different traits may assort independently of one another in gamete production  Leads to genetic diversity What it means: different genes are inherited separately. For example, the gene which codes for eye color is inherited separately from the gene which codes for nose shape.

 Table that shows probability of offspring having a particular trait  Shows a cross (mating)between a male’s gamete with the female’s

**Cross a male with a Female – What are the probabilities of the sexes of the babies? XY X X XX XY **Genotypic Ratio: 2 XY to 2 XX  1:1 (50/50 chance) **Phenotypic Ratio: 2 Males to females  2:2  1:1

Rr R r RRRr rr Dad’s Genotype is Rr and his phenotype is Round Mom’s Genotype is Rr and her phenotype is Round **Genotypic Ratio: 1RR:2Rr:1rr   Write Homozygous Dominant 1 st, then Heterozygous then Homozygous Recessive. **Phenotypic Ratio: 3Round:1Wrinkled  3:1  Dominant first then recessive

 Determine the genotypes of a parent based on offspring.  In a Test cross, cross an unknown genotype to a known recessive (below) T TT t t t t t t t t ttt tt t t T T TT T T If all offspring are tall the unknown Is TT, homozygous dominant If half of the offspring are short and the other half tall the unknown is Tt, heterozygous

 Cross the following and determine the genotypic and phenotypic ratios: › Homozygous yellow pod (YY) with heterozygous yellow pod (Yy) › 2 heterozygous tall plants (Tt) › 1 plant with wrinkled seeds (rr) with a plant that is heterozygous for round seeds (Rr) › A homozygous dominant purple flower (PP) with a homozygous white flower (pp)