
Science
Get flash to fully experience Pearltrees
Earth's Oceans: Tides
Tides are periodic rises and falls of large bodies of water. Tides are caused by the gravitational interaction between the Earth and the Moon. The gravitational attraction of the moon causes the oceans to bulge out in the direction of the moon.Leaf cells have a special feature: pigment-containing chloroplasts in certain cells that enable them to produce energy and their own food through photosynthesis.

