<Li> Smooth endoplasmic reticulum </Li> <Li> Cytosol (fluid that contains organelles, comprising the cytoplasm) </Li> <P> A cytoskeleton is present in all cells of all domains of life (archaea, bacteria, eukaryotes). It is a complex network of interlinking filaments and tubules that extend throughout the cytoplasm, from the nucleus to the plasma membrane . The cytoskeletal systems of different organisms are composed of similar proteins . In eukaryotes, the cytoskeletal matrix is a dynamic structure composed of three main proteins, which are capable of rapid growth or disassembly dependent on the cell's requirements at a certain period of time . </P> <P> The structure, function and dynamic behavior of the cytoskeleton can be very different, depending on organism and cell type . Even within one cell the cytoskeleton can change through association with other proteins and the previous history of the network . </P>

Do both plant and animal cells have a cytoskeleton