The Microbes Within

A WebQuest exploring the effects of endosymbiosis on reproduction, evolution and human health

Introduction - Task - Process - Resources - Evaluation - Conclusion - Teachers


Wolbachia General Biology

Wolbachia endosymbionts
Wolbachia endosymbionts in the filarial nematode Ochocerca volvulus, the causative agent of River Blindness. Image by Mark Taylor, courtesy of the Encylcopedia of Life under a CC-BY-NC-SA license.
  1. Briefly describe the basic biology of Wolbachia.
  2. What is meant by an obligate, intracellular symbiont?
  3. What are the 4 basic reproductive strategies induced by Wolbachia?

Reproductive Strategies

  1. Define the 4 reproductive strategies of Wolbachia.
  2. Why would Wolbachia induce asexual reproduction in its host?
  3. How can we "cure" the host of asexual reproduction?

Human Disease

  1. List and describe two major human diseases associated with Wolbachia.
  2. How did researchers confirm that Wolbachia was actually responsible for these diseases?
  3. How are they being treated?

Speciation in Insects

Black Fly
Adult Black Fly (Simulium yahense) with Onchocerca volvulus emerging from the insect's antenna. The parasite is responsible for the disease known as River Blindness in Africa. Image provided courtesy of the USDA under Public Domain.
  1. What is meant by reproduction isolation? How can it lead to speciation?
  2. How does Wolbachia influence speciation?
  3. How did researchers confirm that Wolbachia may be responsible for speciation in insects?

Vector Control

  1. What is meant by "vector-borne" disease?
  2. Name at least two vector-borne diseases. How might vector-borne diseases be controlled using Wolbachia?
  3. How might Wolbachia help to prevent the spread of malaria?

Viruses/Phage: The Parasites Within

  1. Describe the structure and infection process of bacteriophage.
  2. What is the difference between the lytic and lysogenic lifestyles of bacteriophage?
  3. What is the effect of bacteriophage WO-B within Wolbachia? The host insect? How did researchers confirm this relationship?

Symbiosis & Host-Microbe Interactions

Wolbachia in Insect Testes
Insect testes showing sperm DNA (red) and Wolbachia endosymbionts (green). Image by Michael Clark and Seth Bordenstein, courtesy of the Encylcopedia of Life under a CC-BY-NC-SA license.
  1. Define endosymbiosis. What is the endosymbiotic theory of evolution?
  2. Compare/contrast mitochondria & Wolbachia.
  3. What is horizontal gene transfer? How does it relate to Wolbachia?