Bio 15B - Bio 15B February 11, 2008 True Breeding:...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Bio 15B February 11, 2008 True Breeding: -Experiments with pea plants. -Pollen contained sperm; cut stamens of male (white) plant so that it can’t self fertilize and transferred pollen from stamens to carpel of purple plants. -Purple and white flowering pea plants crossed. Monohybrid Cross (1 trait): - True-breeding : Parents: Purple x White - F1 Generation : All came out as Purple flowers. o Fertilization of F1 generation among themselves - F2 Generation : ¾ are Purple and ¼ are White Results : - There are alternative forms of genes (alleles) - An organism gets one allele from each parents - The alleles separate when gametes form and recombine at fertilization - Alleles can be dominant or recessive Principle of Segregation : organisms have pairs of genes that segregate during gamete formation and come together during fertilization. ~the 2 genes segregated from one another; gametes when fertilized never end up with the 2 gene mixed together; their separated Punett Square: B b B BB Bb B Bb Bb Phenotypic Ratio 1 BB: 2 Bb: 1bb B- Dominant b- Recessive Homozygous- Homozygous (same) Phenotype: Looks; what you see. Genotype: Genetic makeup Gene: allele Dihybrid Cross (2 traits): - P Generation : Round seed (dominant) ( R) / Yellow seed (dominant) ( Y ) x Wrinkled seed (recessive)/ Green seed (recessive) - F1 Generation : RrYy - F2 Generation : 4 possible outcomes: 9/16 yellow round; 3/16 green round; 3/16 yellow wrinkled; 1/16 green wrinkled Principle of Independent Assortment : Each pair of alleles segregates independently during gamete formation.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
~gametes can end up mixed/in different combinations (like the parents) or separated characteristics Huntington’s Disease: disease forming allele form clumps in nerves cells killing them. Only need to inherited one allele in order to have to protein killing allele.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

Bio 15B - Bio 15B February 11, 2008 True Breeding:...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online