1 / 12

Do Now

Do Now. Take out paper (for notes) + homework packet. One of SpongeBob’s cousins, SpongeBillyBob , recently met a cute squarepants gal, SpongeGerdy , at a local dance and fell in love. ( Squarepants is an autosomal dominant trait ).

prentice
Download Presentation

Do Now

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Do Now Take out paper (for notes) + homework packet. One of SpongeBob’s cousins, SpongeBillyBob, recently met a cute squarepants gal, SpongeGerdy, at a local dance and fell in love. (Squarepants is an autosomal dominant trait). A. If SpongeGerdy’s father is a heterozygous squarepants and her mother is a roundpants, what is her genotype? • (hint: you may need to set up a punnett square) • B. If SpongeBillyBob is heterozygous, what are the chances that they will have a squarepants child?

  2. Video • Pay attention to: • Incomplete Dominance • Codominance • Linkage (Thomas Hunt Morgan) • You should be taking notes

  3. Incomplete Dominance • When one inherited allele is not complete dominant over the other allele.

  4. Codominance • When a single gene has more than one dominant allele, allowing both to be expressed at once. NOT TRUE

  5. Which case is it? • A scientist discovers a orange cat on an island. While she is still there, she discovers another cat that looks remarkably the same as this cat, except it is brown. Over the next couple of weeks, she notices red cats, brown cats, and cats that seem to be speckled red and brown. • Which case is this, incomplete dominance or codominance? Justify your answer.

  6. Which case is it? • A scientist discovers a orange cat on an island. While she is still there, she discovers another cat that looks remarkably the same as this cat, except it is brown. Over the next couple of weeks, she notices red cats, brown cats, and cats that seem to be speckled red and brown. • Which case is this, incomplete dominance or codominance? Justify your answer.

  7. Gene Linkage • Which is more common? Case 1 Case 2

  8. What is responsible for this? GENE LINKAGE: • When the gene for two traits are on the SAME chromosome!

  9. Gene Linkage Mapping • Example: Map distance between two genes: Hair color, eye color N = Brown; n = blonde P= Brown; p = blue Step 1: Assume complete dominance NnPp x nnpp • What offspring do you expect? • Given 400 offspring, how many of each do you expect?

  10. But… • You get… • NP: 150 (Brown hair, brown eyes) • Np: 50 (Brown hair, blue eyes) • nP : 50 (Blonde hair, brown eyes) • np: 150 (Blonde hair, blue eyes)

  11. Recombination Frequency Units: centiMorgan (cM) Or a % • Calculate linkage map distance (or recombination frequency) between the two gene loci (locations) by percent of recombination between the two genes. Recombination frequency: • NP: 150 • Np: 50 • nP : 50 • np: 150

  12. Question • What would a higher percentage mean? • The distance between the two genetic loci is greater

More Related