Basic Genetics

Mendel's Experiment
-Mendel wanted to find how traits were passed across generations
-He allowed the plants to self pollinate until he obtained pure breeding plants (the P generation)
-He cross pollinated the peas from the P generation with contrasting phenotypes and called the offspring the F1 generation
-He allowed the F1 generation to self pollinate and got the F2 generation
-He counted the numbers of offspring that got the the parent's phenotype
Basic Laws of Inheritance
-Traits come in more than one form called alleles. (ex: allele for yellow seeds and the allele for green seeds)
-Each organism has two alleles for each trait, one from each parent
-Homozygous: two identical alleles
-Heterozygous: two different alleles
-In a heterozygous organism one trait is dominant (expressed) or recessive (hidden)
-Alleles are assorted independently and randomly
-Other recessive traits are only expressed physically if they are homozygous
-Dominant traits are expressed if it is homozygous or heterozygous
-An organism's genotype is its genetic composition
-An organism's phenotype is its physical appearance


Chromosomal Mutations
Twins