Neversink Pit, Alabama

Neversink Pit, a wet limestone sinkhole in Alabama seen above in 1998, is about 50 feet (15 meters) deep and houses a rare species of fern. The sinkhole was bought in the 1990s by a group of cavers to preserve it for future generations.

Karst is the geologic term for landscapes formed mainly by the dissolving of limestone or dolomite bedrock. In the United States, karst underlies parts of Missouri, Arkansas, Kentucky, Tennessee, northern Alabama, Texas, and most of Florida. Such areas are marked by sinking streams, subterranean drainage, large springs, caves—and, of course, sinkholes.

 

The World's tallest tower

The Burj Dubai tower is pictured during the opening ceremony of the Burj Dubai tower on January 4, 2010 in Dubai, United Arab Emirates.The Burj Dubai, which in Arabic means Dubai Tower, is at 824.55 meters the world's tallest man-made structure.

Interesting facts for Kids-Difference Between Bacteria and Virus

Difference Between Bacteria and Virus

1. Viruses are the smallest and simplest life form known. They are 10 to 100 times smaller than bacteria.

2. The biggest difference between viruses and bacteria is that viruses must have a living host - like a plant or animal - to multiply, while most bacteria can grow on non-living surfaces.

3. Bacteria are intercellular organisms(i.e. they live in-between cells); whereas viruses are intracellular organisms (they infiltrate the host cell and live inside the cell). They change the host cell's genetic material from its normal function to producing the virus itself.

4. There are some useful bacteria but all viruses are harmful.

5. Antibiotics can kill bacteria but not viruses.

6. An example of a disease caused by bacteria is strep throat and an example of an affliction caused by a virus is the flu.