Zooxanthellae

Zooxanthellae

Physiology

• Physical characteristic
  • single-celled mixotrophic microorganisms
  • share the same spherical form that enables them to live within coral

A Close up of many zooxanthellae

• Genetic characteristic
  • part of a group of dinoflagellates
    • Flagellated
    • Thecal Plates
• Zooxanthellae is the name given to a wide array of different algae of the genus Symbiodinium

• Behavior
  • live in the tissues of other organisms
    • Cnidarians (Coral Polyps, Jellyfish)

Visible Zooxanthellae within a coral polyp

• • • Nudibranchs (Sea Slugs)

• • Under-represented in the water column

Mutualistic Relationship with Coral Reefs

• Photosynthesis
  • Corals provide a safe environment and compounds needed for photosynthesis

A diagram of coral symbiosis

• Zooxanthellae provide food (nutrients) for the coral to use in order to secrete calcium carbonate skeleton
• Highly efficient exchange of nutrients
• Relationship has lasted for more than 200 million years
  • Sugar/Carbohydrate Export
  • Amino Acid Export

Environmental Impact & Coral Bleaching

• Bleaching occurs when environmental stress adversely affects the mutually beneficial relationship between the host organism and its zooxanthellae.

Loss of zooxanthellae and pigment

Sources

http://oceanservice.noaa.gov/education/kits/corals/coral02_zooxanthellae.html (accessed on 2/23/13)

http://coralreef.noaa.gov/aboutcorals/coral101/symbioticalgae/ (accessed on 2/23/13)

http://www.biolbull.org/content/137/3/506.short

http://www.int-res.com/articles/meps/71/m071p065.pdf

http://www.int-res.com/articles/meps/180/m180p139.pdf

http://link.springer.com/article/10.1007%2FBF00348077?LI=true

Picture Sources

1. http://www.seaslugforum.net/

2. http://www.coralreefecosystems.org/

3. http://ocean.si.edu/

4. http://www2.fiu.edu/

5. http://ningalooatlas.files.wordpress.com/