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BIO102: Introduction to Evolutionary Biology and Ecology

Unit 1: Mendelian Genetics   We will begin this course by taking a look at how certain features of an organism, such as hair color or bone length, get passed on from generation to generation.  The Augustinian monk Gregor Mendel first discovered the rules of inheritance for these features – more commonly known as traits – through his experiments with pea plants in the 1800s.  These experiments showed that certain traits were always dominant to other traits, meaning that if, for example, a red flower were mated with a white flower, the offspring would always be red because red was the “dominant” trait.  Mendel also found that the passing of certain traits to offspring became remarkably predictable when certain simple ratios were used.  The rules he uncovered when making these observations are now known as Mendel’s Laws of Inheritance.  The idea that traits are passed on from generation to generation is fundamental to understanding how evolution works.

Unit 1 Time Advisory
This unit should take approximately 6.25 hours to complete.

☐    Subunits 1.1: 1.5 hours

☐    Subunit 1.2: 2 hours

☐    Subunit 1.3: 2.25 hours

☐    Assessment: 0.5 hours

Unit1 Learning Outcomes
Upon successful completion of this unit, the student will be able to:
- Distinguish between a phenotype and genotype. - Use Punnett Squares to predict the result of various crosses between individuals with homozygous or heterozygous genotypes, including dihybrid crosses that involve two separate, unlinked characteristics.

1.1 Phenotype/Genotype, Dominant/Recessive Traits, and Homozygosity/Heterozygosity   - Lecture: MIT: Professor Graham Walker’s Introductory Biology: “Mendelian Genetics”

Link: MIT: Professor Graham Walker’s *Introductory
Biology:* [“Mendelian
Genetics”](http://www.youtube.com/watch?v=Sgw-20GsZjE) (YouTube)  

 Also available in:  
 [MP4](http://www.archive.org/details/MendelianGenetics_620)  
 [iTunes
U](http://ocw.mit.edu/courses/biology/7-014-introductory-biology-spring-2005/video-lectures/21-mendelian-genetics/)  

 Instructions: Please watch Lecture 21, titled “Mendelian Genetics.”
 This lecture covers the major topics of Unit 1.  

 Watching this lecture and pausing to take notes should take
approximately 45 minutes.  

 *Note: Some images have been removed from this lecture due to
copyright.*  
    
 Terms of Use: Graham Walker, 7.014 Introductory Biology, Spring
2005. (Massachusetts Institute of Technology: MIT OpenCourseWare),
[http://ocw.mit.edu](http://ocw.mit.edu/)(Accessed January 11,
2011).  License: [Creative Commons BY-NC-SA
3.0](http://creativecommons.org/licenses/by-nc-sa/3.0/us/).  The
original version can be found
[here](http://ocw.mit.edu/courses/biology/7-014-introductory-biology-spring-2005/video-lectures/21-mendelian-genetics/).
  • Reading: Dr. Michael J. Farabee’s Online Biology Book: “Chapter 14: Introduction to Genetics” Link: Dr. Michael J. Farabee’s Online Biology Book“Chapter 14: Introduction to Genetics” (HTML)

    Instructions: First, read the “Glossary of Genetic Terms,” then read the sections “Heredity, Historical Perspective” and “The Monk and His Peas.”  Do not focus on the botany terms related to the garden pea; just know that the physiology of garden peas made them very useful experimental subjects, because Mendel could control their pollination to one another or allow them to self-pollinate.  A “genotype” refers to the specific genes that an organism carries.  A “phenotype” refers to the physical appearance of an organism that results from the combination of these genes and an individual’s environment.

    Reading these sections and taking notes should take approximately 30 minutes.

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

  • Lecture: Khan Academy’s “Introduction to Heredity”

    Link: Khan Academy’s “Introduction to Heredity” (YouTube)

    Instructions: Please click on the link above and watch the lecture in its entirety for an introduction to heredity.

    Watching this lecture and pausing to take notes should take approximately 20 minutes.

    Terms of Use: This video is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License. It is attributed to Salman Khan and Khan Academy.

1.2 Laws of Inheritance: Law of Segregation and Law of Independent Assortment   - Reading: Dr. Michael J. Farabee’s Online Biology Book: “Chapter 14: Introduction to Genetics” Link: Dr. Michael J. Farabee’s Online Biology Book: “Chapter 14: Introduction to Genetics” (HTML)

 Instructions: Read this chapter. It covers both the Law of
Segregation and the Law of Independent Assortment.  

 Reading this chapter and taking notes should take approximately 45
minutes.  

 Terms of Use: Please respect the copyright and terms of use
displayed on the webpage above.
  • Reading: North Dakota State University: Professor Phillip McLean’s Mendelian Genetics: “Mendel’s Second Law”

    Link: North Dakota State University: Professor Phillip McLean’s Mendelian Genetics“Mendel’s Second Law” (HTML)
     
    Instructions: Read the section “Mendel’s Second Law.”

    Reading this section and taking notes should take approximately 45 minutes.

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

  • Reading: North Dakota State University: Professor Phillip McLean’s Mendelian Genetics: “Mendel’s First Law”

    Link: North Dakota State University: Professor Phillip McLean’s Mendelian Genetics“Mendel’s First Law” (HTML)
     
    Instructions: Please read the section “Mendel’s First Law (Law of Segregation).”  Understanding the Law of Segregation is essential in understanding Mendelian genetics.  Mendel’s laws helps to explain how certain characteristics and traits are inherited or passed from one generation to the next.

    Reading this section and taking notes should take approximately 30 minutes.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.

1.3 Punnett Squares   - Reading: University of Arizona’s Biology Project: “Monohybrid Cross Problem Set: Problem 1” Link: The University of Arizona’s Biology Project: “Monohybrid Cross Problem Set: Problem 1” (HTML)
 
Instructions: Please click on the link above, read through the Monohybrid Cross tutorial in its entirety, and complete the problems in order to gain a detailed understanding of the use of Punnett Squares in answering questions about the probabilities of inheritance.

 Reading this tutorial and completing the problems should take
approximately 1 hour.  
    
 Terms of Use: The linked material above is from *[The Biology
Project](http://www.biology.arizona.edu/)*, developed at the
University of Arizona.  Please respect the copyright and terms of
use displayed on the webpage above.
  • Reading: The Saylor Foundation’s “Punnett Square” Link: The Saylor Foundation’s “Punnett Square” (PDF)
     
    Instructions: Please click on the link above and read the article, which will provide you with a solid overview of Reginald Punnett and his contribution to the

    Punnett Square .

    Reading this article and taking notes should take approximately 15 minutes.

  • Web Media: YouTube: The Saylor Foundation: Lynn Carpenter’s “The Punnett Square” Link: YouTube: The Saylor Foundation: Lynn Carpenter’s “The Punnett Square” (YouTube)

    Instructions: Please click on the link above and watch the video.  You will learn about the

    Punnett Square , its uses, and its development.

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

    Terms of Use: This resource is licensed under a Creative Commons Attribution 3.0 License.  It is attributed to Lynn Carpenter and The Saylor Foundation.

  • Lecture: YouTube: Paul Anderson’s Bozeman Biology: “A Beginner’s Guide to Punnett Squares” Link: Paul Anderson’s Bozeman Biology:  “A Beginner’s Guide to Punnett Squares” (YouTube)

    Instructions: Please watch the entire lecture.

    Watching this video and taking notes should take approximately 15 minutes.

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

1.3.1 Backcross   - Reading: The Saylor Foundation’s “Genetic Backcross” Link: The Saylor Foundation’s “Genetic Backcross” (PDF)

 Instructions: Please click on the link above and read this article
on genetic backcrossing and the example of the American Chestnut.  

 Reading this article and taking notes should take approximately 15
minutes.

1.3.2 Test Cross   Note: A test cross is a test that determines the genotype of an organism for a particular trait.  Usually, a test cross involves crossing (or breeding) an organism that has an unknown genotype with an organism that is homozygous recessive for that trait and then looking at the ratio of dominant and recessive phenotypes in order to determine the genotype.  A backcross is a cross between a heterozygous Findividual and one of its homozygous parents. 

  • Reading: The Saylor Foundation’s “Test Cross” Link: The Saylor Foundation’s “Test Cross” (PDF)

    Instructions: Please click on the link above and read this article on the genetic test cross.

    Reading this article and taking notes should take approximately 5 minutes.

1.3.3 Dihybrid Cross   - Reading: The Saylor Foundation’s “A Dihybrid Cross Example Using Mendel’s Sweet Peas” Link: The Saylor Foundation’s “A Dihybrid Cross Example Using Mendel’s Sweet Peas” (HTML)

 Instructions: Please click on the link above and read this article
on the dihybrid cross.  The example presented builds on the
monohybrid cross discussed earlier.  

 Reading this article and taking notes should take approximately 10
minutes.

Unit 1 Review and Assessment   - Assessment: The Saylor Foundation’s “Unit 1 Review” Link: The Saylor Foundation’s “Unit 1 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 1 Review Answer
Key”](http://www.saylor.org/site/wp-content/uploads/2013/11/BIO102_Unit_1_Review_ANSWER_KEY-FINAL.pdf) (PDF).  

 Completing this assessment should take approximately 30 minutes.
  • Assessment: The Saylor Foundation’s “Unit 1 Assessment” Link: The Saylor Foundation’s “Unit 1 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.