In metric terms a square foot is a square with sides 0.3048 metres in length. One square foot is the equivalent to 0.09290304 square metres. Common references: The six floors of the White House (Washington D.C., U.S.A.) have a combined floor-space area of approximately 55,000 square feet.
Description: Volvox is a green algae and the culmination of the volvocine line. It is a hollow sphere made up of a single layer of 500-60,000 biflagellate cells. The flagella beat so as to turn the volvox in circles and therefore propel the spheres in water. Volvox is also polar.
Each little dot you see is a tiny green algae with two flagella. With this the individual organisms propel themselves. They do this in a coordinated manner so that the entire colony can move in one direction. To see Volvox in locomotion is simply breathtaking. This image shows a colony with one large daughter colony. These develop from one one cell inside the sphere. Inside the daughter colony the third generation is already beginning to develop. As well as asexuality Volvox also uses sexual reproduction. The dark spheres are egg-cells. They are fertilized by small packages of sperm. The species depicted is Volvox aureus. It can be up to one millimetre or more in size. It can be found in clear water when the temperatures are not too low. The end of summer is the right time for a good catch with a plankton net. More about this organism can be found in the Micscape article: Volvox