Module 3

Biology of Disease
October 1 – October 7

Module 3 Introduction
Have you ever seen the movie “War of the Worlds’ where it appears that all of humanity will be wiped out and earth will be taken over by aliens? Just when it looks like all is lost the space ships and aliens begin dropping out of the sky because the aliens became sick and liquefied because they succumbed to the microorganisms found in our environment. The aliens could not hack it on earth, but humans and animals could because we have an immune system that protects us from the billions of potential pathogens we are exposed to every day. The immune system in animals has been evolving for 100’s of millions of years and is complex, extremely effective and fascinating to study. Understanding how the immune system works is critical to understanding disease in animals. And knowing how the immune system works will give us insight to aid us in recognizing and monitoring disease in our animals. The following videos are very information dense and the narrator goes through the material very quickly. I would advise that you watch the videos 2-3 times to become familiar with the structures and function of the immune system


  1. Describe bacteria, viruses, and prions.
  2. Describe immune system responses to pathogens.
  3. Explain how the immune system responds to vaccinations.
  4. Explain the causes and effects of overwhelming infections
Estimated Time to Complete
 Instruction  3 hrs
 Assignments  3 hrs
 Collaboration  2 hrs

Learning Activity

Read pages 13 – 23 of the Reindeer Health Manual

Read this article on Immune Seasonality.

Watch the following four videos on the immune system and then follow up with the powerpoint presentations as a review.


Quiz 3 “Biology of Disease”
Due October 7th before midnight.

Reflection and Writing
Due October 7th before midnight.

The tundra ecosystem is referred to as a “pulsed” system. The responses of microorganisms, plants, and animals to the abrupt changes in temperature, photoperiod and solar radiation occur and dissipate quickly or in “pulses.” Leaves emerge, grow to maturity and senesce in a few short months. The responsiveness of the reindeer’s immune system is also pulsed. Their immune system ramps up in the spring during calving and in the fall during rut, but is depressed during winter. What are the possible advantages of reindeer having a “pulsed” immune system?