Ligaments. Ligaments, similar to tendons, help to hold bones in place.

Chlorofluorocarbons. "Freon" is a registered trademark for DuPont's brand of chlorofluorocarbons.

The Floor. Lobsters use their antennae as sensors to navigate the murky environment at the bottom of the ocean.

Virus. A virus can be 1,000 times smaller than a single bacterium.

Organs. There are 78 different organs in the human body.

Index Fossil. Index fossils are used to define and identify geologic periods or faunal stages.

1,350,000 M.P.H.. The Milky Way contains roughly one-hundred billion stars.

Biogas. Biogas results from organic matter breaking down in the absence of oxygen.

Oceanographers. Oceanography, a branch of Earth science, is also called "marine science".

England. A CAT scan is a series of x-rays that are assembled by a computer to create detailed images.

Wind. Gale warnings are issued when winds of 34-47 knots are expected.

Occluded Front. An occluded front is the result of cyclogenesis when a cold front overtakes a warm front.

Moon. The moon is about 1/80th the size of the Earth in mass.

746 W. Horsepower rates engine performance.

P. Sometimes animals can actually hear the P waves of an earthquake before the waves are felt.

Indian Summer. "Indian Summer" occurs after the trees have lost their leaves, but before snowfall.

Erythrocyte. Erythrocytes are responsible for delivering oxygen to body tissues.

South America. A fully grown Green Anaconda is the world's largest snake, weighing in around 550 pounds

Constellations. There are 88 official constellations in the night sky.

10. The U.S. Metric Conversion Act of 1975 proposed no date by which the U.S. conversion would be complete.