Mendel stated that physical traits are inherited as “particles”
Mendel did not know that the “particles” were actually chromosomes and DNA
Traits in Pea Plants Pea plants have many different traits Some traits are dominant over others Allele: a form of a gene (different bases along the DNA) Dominant: allele that is expressed (regardless of its counterpart allele); represented by a capital letter (e.g. T) Recessive: allele that is expressed only when its counterpart allele is also recessive ; represented by a small letter (e.g. t) Examples of traits in pea plants
What alleles will the offspring of two parents have?
What will the offspring look like?
Genotype: the combination of alleles for a trait e.g. TT, Tt, tt Phenotype: the physical feature resulting from a genotype e.g. tall, short Short
GENOTYPE AND PHENOTYPE Genotype of alleles: P = purple flower p = white flower All genes occur in pairs, so 2 alleles affect a characteristic Possible combinations are: Genotypes PP Pp pp Phenotypes purple purple white