Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
5 Cards in this Set
- Front
- Back
What kind of microbes grow near the top of the column? Give two examples. |
Microbes that grow here gain energy from the sun but also use organic acids as a carbon source. They are photoheterotrophs. Two examples are Rhodospirilium and Rhodomicrobium. |
|
What kinds of organisms grow just below the top? Give an example. |
Sulfur oxidizing bacteria grow here meaning they can gain energy from H2S or S and turn it into SO4. They can also synthesize their own organic matter from CO2 gas. Thus they are chemoautotrophs. Examples include Thiobacillus and Beggiatoa. |
|
What kind of organisms grow just above the bottom layer of the tube (red to purple)? Gives examples. |
In this layer organisms process sulfates or sulfur just like the other middle layer of the column. CO2 + H2S -> C6H12O2 + 6S. Because they have photosynthetic pigments they use anaerobic photosynthesis to obtain enery. Clostridium and Chromatium are examples. |
|
What kind of microbe lives at the bottom of the column? What does it use for energy? Give an example. |
Sulfur reducing bacteria live in this layer of the column. They turn SO4 into H2S. They can also take Fe and H2S and turn it into ferrous sulfide FeS resulting in a black ppt. A green sulfur bacteria called Desulfovibrio is and example. |
|
What types of microbes are found throughout the column (oxygen requirments, nutritional type...) at top, middle and bottom of tube? |
Top - aerobic, photoheretotrophs Just below surface - microaerophilic, sulfur oxidizing, chemoautotroph Middle - anaerobic photosynthesis, sulfur oxidizing, chemoautotroph? Bottom - anaerobic, sulfur reducing, iron, can use Fe + H2S -> FeS |