It is hypothesized that RNA may have evolved before DNA because RNA molecules were the first molecules synthesized by Miller and Urey
are more important to genetic inheritance than DNA
can catalyze a variety of biologically important reactions
are found in more modern cells than are DNA molecules

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.

several tissues working together form an organ, and several organs together make up an organisms.

the group of cell that carries out special jobs are tissue.