7. what are the advantages of large organisms being multicellular
Multicellular organism Multicellularity allows an organism to exceed the size limits normally imposed by diffusion: single cells with increased size have a decreased surface-to-volume ratio and have difficulty absorbing sufficient nutrients and transporting them throughout the cell. Multicellular organisms thus have the competitive advantages of an increase in size without its limitations. They can have longer lifespans as they can continue living when individual cells die. Multicellularity also permits increasing complexity by allowing differentiation of cell types within one organism.
Biomass (ecology) The total live biomass on Earth is about 550 - 560 billion tonnes C,[1][5] and the total annual primary production of biomass is just over 100 billion tonnes C/yr.[6] The total live biomass of bacteria may be as much as that of plants and animals[7] or may be much less.[8] The total number of DNA base pairs on Earth, as a possible approximation of global biodiversity, is estimated at (5.3Â±3.6) x 1037, and weighs 50 billion tonnes.[9][10] In comparison, the total mass of the biosphere has been estimated to be as much as 4 x 1012 tonnes of carbon.[11]