1.(4) To identify the distribution of the cortical potential evoked by C-fiber inputs (C-CEP) on the surface and in the deeper layer of S I , indicating that C-CEP occurcd in the inner or somatosensory cortex;
2.Promeristem is composed ofthree layers of cells in root tip,of them,outer layer of cells form the epidermis and root cap,centraland inner layers of cells sepratedly form the cortex and vascular cylinder.
