pure breed
A population that is inbred enough that offspring are always very similar to their parents
Hybrid
when you cross two pure breeds
Mendel and the Pea
He bred two pure breeds and found that all had one trait. f2 generation had a bit of another trait but still mostly one trait. F2 generation had a 3:1 ratio of traits.
When two pure breeds cross, it is a
100 percent dominant but heterozygous. when you breed again, this has F2 generation of 3:1 ratio
Mendel’s interpretation
he said that each parent had 2 factors for yellow and 2 for green. each factor is distributed to offspring from each parent RANDOMLY. offspring are hybrid but yellow is dominant so all have yellow
Principle of segregation
In adults genes exist in pairs, which segregate randomly when gametes are formed and then recombine into pairs at fertilization. In other words, a sperm or egg (haploid) has only one copy of each gene, while a (diploid) adult has two copies.
Principle of Dominance
If an individual is heterozygous (has two different versions of the same gene), then one version will dominate and the other will disappear (recede in Mendel’s terms). The recessive version of the gene will only show up as a trait when an individual inherits two copies of the recessive, or is homozygous recessive.
Genotype:
combination of alleles (YY, Yy or yy)
phenotype
trait (blue or green eyes)
heterozygous genotype
Hybrid. Two different alleles.
“factors”
genes
monohybrid cross
mating between hybrids for one gene using (Yy, Yy)
