i believe the answer is "A fundamental role". hope this helps.
Its made up of microtubules, microfilaments and intermediate filaments. They give the cell shape and organize its parts
Cell walls and chloroplasts are structures present in plant cells but not animal cells
A shield vol may be produced by hot spots which lay far away from the edges of tectonic plates. Shields also occur along the mid-oceanic ridge, where sea-floor spreading is in progress and along subduction related volcanic arcs.
