Loading...

BIO102: Introduction to Evolutionary Biology and Ecology

Unit 2: Heredity and Inheritance   We have come to understand that the relationship between genotype and phenotype is not always as simple as determining which genes are dominant and which are recessive.  Human height, for example, does not come in just two phenotypes (“short” and “tall”), but a continuous variation.  In this unit, we will look at other major types of inheritance, that is, types of inheritance that are not just dominant versus recessive.  These other types become crucial in evolution.  As organisms become more complex, adapting to the environment requires much more than the expression of just two dominant and recessive phenotypes for any given trait.

Unit 2 Time Advisory
This unit should take approximately 3.75 hours to complete.

☐    Unit 2 Reading: 1 hour
☐    Subunit 2.1: 1 hour

☐    Subunits 2.2-2.4: 1 hour

☐    Subunit 2.5: 0.25 hours

☐    Assessment: 0.5 hours

Unit2 Learning Outcomes
Upon successful completion of this unit, the student will be able to: - Understand the process of meiosis and how it affects inheritance, for example, via recombination. - Identify and give examples of situations in which traditional Mendelian Laws of Inheritance do not apply. - Use Punnett Squares to predict inheritance for traits that involve co-dominance, incomplete dominance, and sex-linkage.

  • Reading: Dr. Michael J. Farabee’s Online Biology Book: Chapter 15 “Gene Interactions” Link: Dr. Michael J. Farabee’s Online Biology Book“Chapter 15: Gene Interactions (HTML)

    Instructions: Read this chapter, which covers the topics in Unit

    Reading this chapter and taking notes should take approximately 1 hour.

    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.

2.1 Genes and Inheritance: Alleles, Meiosis, Recombination, Diploid Cells, and Haploid Cells   - Lecture: Massachusetts Institute of Technology: Graham Walker’s Introductory Biology: “Mitosis and Meiosis” Link: Massachusetts Institute of Technology: Graham Walker’s Introductory Biology“Mitosis and Meiosis” (YouTube)

 Also available in:  
 [MP4](http://www.archive.org/details/MitosisAndMeiosis)  
 [iTunes
U](http://ocw.mit.edu/courses/biology/7-014-introductory-biology-spring-2005/video-lectures/22-mitosis-and-meiosis/)  

 Instructions: Watch Lecture 22, titled “Mitosis and Meiosis.”  This
lecture will cover the topics in subunit 2.1.  

 Watching this lecture and pausing to take notes should take
approximately 1 hour.  

 *Note: Some images have been removed from this lecture due to their
copyright status.*  

 Terms of Use: This resource is licensed under a [Creative Commons
Attribution-NonCommercial-ShareAlike 3.0
License](http://creativecommons.org/licenses/by-nc-sa/3.0/).  It is
attributed to Graham Walker and [MIT
OpenCourseWare](http://ocw.mit.edu/index.htm).

2.2 Incomplete Dominance   - Lecture: Massachusetts Institute of Technology: Graham Walker’s Introductory Biology: “Diploid Genetics” Link: Massachusetts Institute of Technology: Graham Walker’s Introductory Biology“Diploid Genetics” (YouTube)

 Also available in:  
 [MP4](http://www.archive.org/details/DiploidGenetics)  
 [iTunes
U](http://ocw.mit.edu/courses/biology/7-014-introductory-biology-spring-2005/video-lectures/23-diploid-genetics/)  

 Instructions: Watch Lecture 23, entitled “Diploid Genetics.”  This
lecture will cover the material in subunits 2.2-2.5.  

 Watching this lecture and pausing to take notes should take
approximately 1 hour.  

 *Note: Some images have been removed from this lecture due to their
copyright status.*  

 Terms of Use: This resource is licensed under a [Creative Commons
Attribution-NonCommercial-ShareAlike 3.0
License](http://creativecommons.org/licenses/by-nc-sa/3.0/).  It is
attributed to Graham Walker and [MIT
OpenCourseWare](http://ocw.mit.edu/index.htm).

2.3 Codominance   Note: This subunit is covered by the lecture under subunit 2.2.

2.4 Polygenic Inheritance   Note: This subunit is covered by the lecture under subunit 2.2.

2.5 Sex-Linked Inheritance: Linked Genes to Sex Chromosomes and X-inactivation   - Lecture: YouTube: Khan Academy’s “Sex-Linked Traits” Link: YouTube: Khan Academy’s “Sex-Linked Traits” (YouTube)

 Instructions: Please click on the link above and watch the lecture
in its entirety for an introduction to sex-linked traits.  

 Watching this lecture and pausing to take notes should take
approximately 15 minutes.  

 Terms of Use: This resource is licensed under a [Creative Commons
Attribution-NonCommercial-ShareAlike 3.0 United States
License](http://creativecommons.org/licenses/by-nc-sa/3.0/us/). It
is attributed to Salman Khan and [Khan
Academy](http://www.khanacademy.org/).

Unit 2 Review and Assessment   - Assessment: The Saylor Foundation’s “Unit 2 Review” Link: The Saylor Foundation’s “Unit 2 Review” (PDF)

 Instructions: Please click on the link above and work through the
problems.  When you are finished, check your work against The Saylor
Foundation’s [“Unit 2 Review Answer
Key”](http://www.saylor.org/site/wp-content/uploads/2012/11/BIO102_Unit_2_Review_ANSWER_KEY_FINAL.pdf) (PDF).  

 Completing this assessment should take approximately 30 minutes.
  • Assessment: The Saylor Foundation’s “Unit 2 Assessment” Link: The Saylor Foundation’s “Unit 2 Assessment” (HTML)

    Instructions: Please complete the linked assessment.
     
    You must be logged into your Saylor Foundation School account in order to access this quiz.  If you do not yet have an account, you will be able to create one, free of charge, after clicking the link.