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Showing all videos (Page 24)
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5:01
Voice Thread Tutorial
Uploaded Sep 10, 2016
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7 Billion: How did we get so big so fast?
It was just over two centuries ago that the global population was 1 billion — in 1804. But better medicine and improved agriculture resulted in higher life expectancy for children, dramatically increasing the world population, especially in the West.
Uploaded Feb 27, 2018
As higher standards of living and better health care are reaching more parts of the world, the rates of fertility — and population growth — have started to slow down, though the population will continue to grow for the foreseeable future.
U.N. forecasts suggest the world population could hit a peak of 10.1 billion by 2100 before beginning to decline. But exact numbers are hard to come by — just small variations in fertility rates could mean a population of 15 billion by the end of the century. - Bill Nye: Food Webs Uploaded Feb 14, 2018
- c. elegans responding to touch Uploaded Sep 22, 2018
- EcoColumn Part 1 (Building Instructions): Cutting the Bottles Uploaded Jan 31, 2018
- EcoColumns Part 2: Filling with Soil, Sand and Gravel Uploaded Jan 31, 2018
- EcoColumns Part 3: Flushing and Unclogging Uploaded Jan 31, 2018
- EcoColumns Part 4: Planting Seeds Uploaded Jan 31, 2018
- EcoColumns Part 5: Making the Aquatic Chamber Uploaded Jan 31, 2018
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How Ecosystems Work: Ecology
Segment from the program How Ecosystems Work: Energy Flow and Nutrient Cycles.
Uploaded Oct 28, 2018
Entire Movie Description
Looks at the processes that are fundamental to all ecosystems. First the concepts of primary productivity, trophic levels, food chains, energy pyramids and the flow of energy through ecosystems are introduced. The program then explains how carbon, nitrogen, phosphorous and water cycle through ecosystems and how human activities can disrupt these cycles and throw them out of balance leading to accelerated eutrophication in lakes in the case of phosphorous imbalances and global warming in the case of carbon imbalances.
