variations to simple dominance its not always as straight forward as it seems…
TRANSCRIPT
VARIATIONS TO SIMPLE DOMINANCE
Its not always as straight forward as it seems…
THE PROBLEM…
• A red carnation is crossed with a white carnation. The resulting flowers are all pink.
• What is up with that?
Incomplete Dominance
– Neither allele dominates the other
– Phenotype is intermediate
– Red flower + White flower = pink flower
– Tall plant + Short plant = medium plant
THE SYMBOLISM ISSUE
• Red is not dominant• White is not recessive• We can no longer use capital and lower case
letter as symbolism
THE SYMBOLISM ISSUE
• We use a base letter – C for “color”
• And a superscript to indicate which one.
INCOMPLETE DOMINANCETHE MONOHYBRID CROSS
CROSS TWO F1 OFFSPRING
CROSS TWO PINK FLOWERS
THE PUNNET SQUARE
CODOMINANCE
– CO MEANS SHARED OR DONE TOGETHER
– Is similar to Incomplete dominance– BUT Instead of blending, – both traits show up!
WADDING ROCKS!!!!
I am a squirl
Do Humans taste like chicken ?
CODOMINANCE– BOTH TRAITS SHOW UP!!!– Black chicken + White chicken = chicken with
both black feathers and white feathers
CODOMINANCE– BOTH TRAITS SHOW UP!!!– BROWN horse and a WHITE horse produce
a roan horse – both BROWN hairs and WHITE hairs…