Module 1 Intro
1. Module 1 Intro
1.7. Page 4
Module 1—Energy Flow and the Cycling of Matter
Try This
TR 2. About 2% of solar energy is used for photosynthesis. Where’s the other 98%?
Explain where the other 98% of solar energy goes. Predict what would happen if there were fluctuations (an increase or a decrease) in these percentages. Also predict what might cause these changes. “Figure 1.4” on page 11 in your textbook may be helpful.
Read
Read “Energy for Life in the Deep Ocean” on pages 12 and 13 of your textbook.
Self-Check
SC 3. Answer question 7 on page 13 of the textbook.
Self-Check Answers
SC 3. Chemosynthesis is similar to photosynthesis because they both use one form of energy to create the organic molecules required for life. This is the beginning of energy flow in a system lacking light.
A difference is that chemosynthetic organisms use the energy from splitting hydrogen sulfide bonds instead of energy from the Sun. Chemosynthetic organisms produce sulfuric acid instead of oxygen. Chemosynthetic organisms are mainly bacteria.
Watch and Listen
A Closer Look at Producers and Chemosynthesis
Discovery: Arctic Hydrothermal Vents
The northernmost hydrothermal vent fields in the world were discovered in late July 2005 on a research expedition northwest of Norway.
Adam Schultz, COAS geophysicist who has studied hydrothermal systems since the 1980s, was part of the collaborative expedition with the University of Bergen, Norway. An instrument he created, called the Medusa Isosampler, played a key role in documenting the characteristics of the new vent fields.
Hydrothermal vents—also called “smokers” or “chimneys”—form along the Mid-Ocean Ridge, an area along the ocean floor where the Earth’s crust splits apart and new crust bubbles up in the form of lava from the mantle. The ridge is the Earth’s largest geologic feature; it zips up and down the middle of the world’s ocean basins like seams on a baseball, and is considered one of the most extreme environments on Earth.
“I’ve seen a lot of hydrothermal systems all over the world’s oceans,” Schultz said, “and these Arctic fields are spectacular.
“There is also a vast low-temperature field that supports a diverse community of life, including large sea-lilies that sit atop mineral-bacterial chimney-like structures that look like pineapples. That is a particularly strange form of vent, because the fluids come out at temperatures only a fraction of a degree above the temperature of the background seawater, and that is very cold—below zero Celsius—which is only possible in the Arctic.”
Much of the Arctic Ridge system is unexplored, and prior to this discovery, a vent field on the shelf of Iceland was the only one scientists had ever laid eyes upon. In marked contrast to that Icelandic field, the new fields are replete with animal life.1
1“Discovery: Arctic Hypothermal Vents,” Ocean & Air–A Magazine of Innovation in Earth Systems Science
<http://oceanandair.coas.oregonstate.edu/index.cfm?fuseaction=content.display&pageID=91>;, 4 September 2007. Reproduced by permission.
Discoveries like those discussed in the article explain how organisms are able to live in extreme environments where light is not available for producers to capture solar energy.
Listen to a past episode of “Quirks and Quarks,” where scientists talk about the process of chemosynthesis as it occurs in the most extreme conditions of deep-sea volcanic vents. To get to this site, enter the key words “Quirks and Quarks CBC” into a search engine. This should get you to the main Quirks and Quarks CBC website of the CBC radio science program. Once there, type in “Extreme Living: Deep Sea Vents” into the CBC search bar in the top-right corner of the page. Listen to this podcast with the following Try This questions in mind.
Try This
Scientific Inquiry
TR 3. The discovery of deep-sea organisms using chemosynthesis is listed by the scientists in the “Quirks and Quarks” episode as one of the top three discoveries in science. What is significant about chemosynthesis that allows it to open other avenues of theory?
TR 4. How did the discovery of microbes in geothermal vents lead to the possibility of new technology?
TR 5. What other hypotheses have been formed due to the discovery of these chemosynthetic organisms?