The producers are placed at the bottom level in energy pyramid and are prime factor in the aquatic eco system which provides energy and perform photosynthesis with the help of water,sunlight and chlorophyll.
The filter feeders are those that feeds upon small particles that are present in the water.
Grazers are those organisms that feeds on producers like phytoplanktons.
Carnivores are those organisms that feeds on herbivores.
It says that there are eight four-base repeat unites that make up the remaining 32 bases. This means that it 8 x 4 = 32. Then from 32 + 9 = 41 is how you get all of the bases in the original. However, if there were to be 10 repeat units then it would be <u><em>10</em></u> x 4 = 40. Then from there you would get 40 + 9 = 49. Hope my explanation helped somewhat.
