Chemical Defense in the Marine Sponge

Introduction

There are over 5,000 species of aquatic, marine Porifers (sponges), these animals vary in size, shape, and color. They have a cellular level of organization which is commonly refered to as a cluster of protozoa living together, a colony. Each cell, in a sense, is independent from the others. Together they form the necessary structure to filter food from the water. They reproduce asexually by budding or fragmentation or sexually by releasing gametes into the water. They are classified by the type of skeleton. Sponge's skeletons may be calcium carbonate or silica (glass sponge) for example. They are the only animal in which digestion occurs within the individual cells.
These animals are sessile, staying attached to the same place their whole life. How do they avoid predation?


How to use this web site

This web site on Sponge self defense is a self contained unit. It can be completely perused as a series of web pages. For lecture purposes, the Biology and Defense sections, can be downloaded as powerpoint slides for use in front of the class. The Uses section is a Word document which can be viewed on the web or downloaded and printed out as a handout, The activities lab can be downloaded and printed out in its pdf format for use during the lab exercises.


Outline and Tasks

  1. Introduction - Nathan Blackner, Tim Floto
  2. Objectives/Goals - Tim Floto
  3. Lesson Plan - Jerri Weyer.
  4. A little bit about sponges - ecology, diversity, natural history, anatomy and physiology in general [html] [ppt] - Jerri Weyer.
  5. There are a variety of sponges and a variety of chemical defenses [html] [ppt] - Nathan Blackner, Mark Marchino
    1. What are the defensive natural products?
    2. How are they produced?
    3. How do they affect predators?
    4. Have any predators been able to get around this defense and how?
  6. Uses of Sponge Chemical Defense Natural Products [html] [doc] - Mark Marchino
  7. Activities/Lab [html] [pdf] - Jocelyn Miller
  8. Assessment (Each section will have an quiz at the end that tests the students grasp of the subject - All
  9. Interesting Links - Tim Floto
  10. Outline, Organization and Maintenance - Tim Floto