Class Notes (810,488)
Canada (494,139)
BIOL207 (111)

BIOL 207 Lecture Note BUNDLE (October 23 - December 2)

79 Pages
Unlock Document

University of Alberta
Biology (Biological Sciences)
Mike Harrington

BIOL 207 October 23 2013 Lecture 18 Interaction Between GenesPart 1 contLecture 19 Interaction Between GenesPart 2 Complimentary Gene InteractionsTwo genes are both needed to produce a WT phenotypeEx Harebell o Two white flowers cross to create blue coloured flowerF2 generation has a 97 ratio bluewhite o ExplanationTwo enzymes in the same pathwayWhite precursorwhite intermediateblue end product o A different enzyme is needed at each transitionOr there are 2 subunits of one enzyme Duplicate Gene ActionOnly one of 2 is needed to produce the wild phenotypeF2 generation has modified 9331 ratio 151 o ExRed flower AABB crossed with aabbF2 selffertilizeF3 generation is 15red1white Continuous VariationVariations in gene expression o ExRange of hair coloursRange in human heightRange in skin tone o There are no distinct expressionsOpposite of continuous variationdiscontinuous variationDistinct phenotypes are seen o ExPetal colour in a hypothetical flowerIf there is one gene and there was continuous variationPpurple and white purebreeding flowerF2121 ratio purplepinkwhiteIf there are two genesPpureple and white purebreeding flowers AABB crossed with aabbF29331 ratio of colours purplelightpurplelightpinkwhite Recessive epistatisOne genes recessive phenotype is interrupting expression of another second geneEx Colour of blue eyed Mary Plants o Magenta phenotype takes over blue pigment o F2 has modified 9331 ratio934bluemagentawhite unpigmented plantswhite you can tell whether or not they would have been blue or pigmentedwpigment w no pigment m blue pigmentmmagentaDominant epistasisDominant phenotype of one gene covers up that of anotherEx Onion o AllelesIno pigmentipigmentRredryellow o Modified 9331 ratio1231 whiteredyellow o Biological ExplanationWhite precursorPrefers a pathway where I allele is presentleads to white pigment end productAlternative pathway iiyellow pigmentIf R allele is present you will get red pigmented endproduct Start of Lecture 19 Interactions Between GenesPart 2How do you provide a biological explanation for a classical genetics experiment o Start with the simplest explanation possibleAutosomalNo X or Y linked1 gene2 Are they linked or is there gene interaction2 alleles3 allelesComplete DominanceAllele interactionsIClicker Question o Question A black dog mates with a white dog and all the puppies have black fur Can this scenario be explained with the 1 gene autosomal 2 alleles and complete dominance explanation o Answer YesIClicker Question o Quesiton F1 generation of the aforementioned dogs are intercrossed to get a resulting F2 generation consisting of 916 black dogs 416 yellow dogs and 316 brown dogs Can we explain this scenario using the 2 genes autosomal unlinked no interaction explanation o Answer No
More Less

Related notes for BIOL207

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.