On Friday in Biology we started off class by turning in our homework which was 11.3 Cornell Notes and took out our packet pages 34-35 for a homework stamp. Afterwards we began with practicing some dihybrid problems to help us review, we also went over homework on packet pages 33-35. In the earlier chapeter we talked about genes being either strictly dominant or recessive, but thats not really true of living things, so we took notes explaining why some genes are different and they have two different alleles fo one trait.
* refer to notes below for explanation*
* refer to notes below for explanation*
~Incomplete Dominance~
- Alleles are NOT dominant or recessive
- Cross between 2 phenotypes produces a third phenotype which is a BLENDING of trhe two traits
- Examples:
straight x curly = wavy hair red x white = pink
Steps To Incomplete Dominance
- Assign Letters: Red Flower = R White Flower = W
- State parental cross ~ RR x WW
- Determine parental Gametes ~ R, R, W, W
- Punnett Square
Genotypic Ratio: 100% RW Phenotypic Ratio: 100% Pink
Co-Dominance
- Both alleles are dominant and expressed EQUALLY...NOT blended
Example : HAir color in cows red x white = ROAN (both red and white hair)
Homework: Read 14.1 in textbook & do packet pages 39-46 due monday
***Page 39 in packet walks you through an example problem if your
having trouble with dihybrid crosses***
the next scribe is Amanda
