Lesson: Microorganisms & Algae

Notes- (non-Animal) Life in the Oceans

Viruses: non-living intracellular parasites that use infected host for reproduciton

- huge diversity and huge numbers (100,000,000,000/L of seawater)

- in most of nature individual viruses attack only one or a few species, but marine viruses are often broad in their infections

Bacteria: single celled organisms that lack nuclei

- huge variety and huge numbers (10,000,000,000/L of seawater)

*Archaebacteria - ancient life that can survive in extremely hostile environments

-thermophiles found in and around black smokers and other hydrothermal vents

-halophiles found in extremely salty conditions

*Cyanobacteria - ancient life that developed photosynthetic abilities

*Decomposers - break down dead organisms, especially those that sink to the benthic zone

*Infectious Parasites - cause infections and other diseases within their hosts

Fungi: single/multicelled heterotrophs

*Decomposers of dead material

*Infections Parasites - found in algae, plants (ex. mangrove) and animals

Plants: multicelled photosynthetic autotrophs

- generally not found in saline environments (with a few exceptions - mangrove/eelgrass)

- more common in the brackish transition zones and salt marshes

Lesson: Microorganisms & Algae

1. How do viruses fit into the ocean ecosystem?
2. Bacteria are major factors in oceans- describe the ways in which bacteria are important.
3. Why are plants and fungus not found in great numbers in oceans?
4. What are the general characteristics and adaptations of algae and other photosynthetic Protista?
5. How can algae and algae-based products be used by humans?