Genetics - Mendel Flashcards
Who was Gregor Mendel
Austrian Munk, Gardener, and Mathematician ; from the late 1800s
What did Mendel do
Mendel created over 20,000 crosses between Sweet Pea plants and took meticulous data on 7 traits over multiple generations.
What did Mendel discover
Mendel discovered the fundamental laws of inheritance
What was Mendel’s work not recognized as important at the time it was published.
There were no microscopes powerful enough to see meiosis, which would prove Mendel’s work
Allele definition
An alternative form of a gene, “factors”
Dominant definition
Allele choice that is always expressed
Recessive definition
Allele choice that is hidden unless both choices are recessive (takes two recessive alleles to show)
Homozygous definition
Same allele in a fertilized egg (zygote)(SAME)
Heterozygous definition
Different allele choices in a fertilized egg (zygote)
Genotype definition
Genes contain alleles that describe the information on the chromosomes
Phenotype definition
The physical characteristics of an organism (this is what Mendel was calculating)
What is a punnett square
A genetic diagram that allows us yo calculate the probability of traits
What was Mendel’s parental generation of Sweet Pea Plants
Purple flowers (TT) and White flowers (tt)
What was Mendel’s second generation
All Purple flowers (All Tt)
What was Mendel’s third generation
3:1, 3 Purple, 1 White
Genotype = TT, Tt and Tt, tt
What are the three laws made by Mendel
Law of Dominance, Law of Segregation, and Law of Independent Assortment
What is the Law of Dominance
States that if you possess a dominant “factor” allele it will be expressed in the organism
What is the Law of Segregation
Parents possess two copies of an allele but give only one to the offspring
Law of Independent Assortment
Traits are not linked, they assort independently of each other
What are the three possible patterns for a Monohybrid cross
Homo Dom x Homo Rec
Hetero x Hetero
Hetero x Homo
What is the genotype and phenotype of Homo Dom x Homo Rec cross
Genotype: 100% Hetero
Phenotype: 100% Dom Trait
What is the genotype and phenotype of Hetero x Hetero cross
Genotype: 1:2:1 TT, Tt, Tt, and tt
Phenotype: 3:1 Dom to Rec
What is the genotype and phenotype of Hetero x Homo Dom cross
Genotype: 50% TT, TT, Tt, Tt
Phenotype: 100% All Dom Trait
What is the genotype and phenotype of Hetero x Homo Rec cross
Genotype: 50% Tt, Tt, tt, tt
Phenotype: 50% (Dom 50%, Rec 50%)
