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BIOL 3011: Genetics (Gotesman): Unit 4: Extension of Mendelian Heredity

Genetics: BIOL 3011

Topics for Unit 4: Extension of Mendelian Heredity

Lecture 7: Terminology, Single gene extension

Lecture 8: Multifactorial and multiple gene extension, metabolic pathways.

At the end of this unit you should be able to:

  1. Demonstrate understanding of the connection between phenotype and genotype, and how these relationships can give rise to altered Mendelian ratios
  2. Demonstrate understanding of the assumptions underlying basic Mendelian genetics
  3. Demonstrate understanding of the genetic consequences of modifying these assumptions
  4. Demonstrate understanding of the concept of biochemical pathways and the genetic analysis of pathways

Readings: Extension of Mendelian Heredity (Unit 4)

External Links - read chapters online (internet connection required)

PDFs: for viewing content offline and printing.
EPUB: Electronic book format file, for viewing on mobile devices.


Seto, Jeremy. “Co-Dominance and multiple alleles.” Biology OER, OpenLab New York City College of Technology (NYCCT),

OpenStax, Characteristics and Traits. OpenStax CNX. Jun 13, 2017

OpenStax, Laws of Inheritance. OpenStax CNX. Feb 24, 2014

Videos: Gene Extensions (Unit 4)

[Bozeman Science] (2012, Apr. 21) Chromosomal Genetics [Video File]. Retrieved from

Useful genetics -problem solving examples -a little confusing.

[Useful Genetics] (2014, Jan. 27) Lecture 6H - Following alleles through generations [Video File.] Retrieved from
[Useful Genetics] (2014, Jan. 22) Lecture 3G - All about dominance [Video File.] Retrieved from
[Biology Rangitoto] (2012, Aug. 7) Metabolic pathways (B2.7-3.3) [Video File.] Retrieved from
[Useful Genetics] (2014, Jan. 22) Lecture 3I - Gene interaction in biochemical pathways [Video File.] Retrieved from