BIO 181 Lecture 2.5

Lecture 2.5: Exceptions to Mendelian Patterns


Traits that obey Mendel’s principles, which are quite creatively called Mendelian traits, are rare, which is one reason why Mendel had such a difficult time propagating his ideas during his lifetime. Here we examine some of the simpler violations of his principles; but remember, the one part of his hypothesis that remains in our modern theory is the particulate nature of genetic determinants.


  1. Read Sections 14.5 and 14.6 of the textbook.
  2. Download Lec 2.5 slides.
  3. Do one of the following:
    1. In-person section: Attend Lecture 2.5.
    2. Online section: Watch the following videos:
      1. Video 2.5.1, Incomplete Dominance.
      2. Video 2.5.2, Codominance.
      3. Video 2.5.3, Sex-Linked Traits.
      4. Video 2.5.4, Non-independent Traits.
  4. Complete the questions on Study Guide 2.5.


After completing the activities, log into Canvas, launch BIO 181 and complete Lecture 2.5 Quiz.

This entry was posted in BIO 181. Bookmark the permalink.