This chapter describes the absorption and transport pathways within the plantPlant, mentioning the mechanisms and dynamicsDynamics associated with these pathways in seedsSeeds, rootsRoot, stemStem and leaves. Nanoparticles infiltrate the seedSeeds coat and enhance germinationGermination and seedSeeds health. RootRoot cellsCell absorb nanoparticles and move via two specific pathways, the apoplastApoplast and the symplastSymplast. This absorption is impacted by the nanoparticles chemical compositionChemical composition, surface chargeSurface charge and size, in addition to root exudatesRoot exudates andSoil micro-biome soil microbesSoil microbes. Nanoparticles continue their path via the vascular system of the stemStem to the leaves. Leaves absorb nanoparticles via the epidermisEpidermis and stomataStoma. Nanoparticles move via two extracellular pathwaysExtracellular pathways and plastidsPlastids. The effectiveness of these pathways is related to many factors, including the nanoparticles chemical and physical properties, the species of plantPlant and environmental factorsEnvironmental factors. The chapter highlights the nanoparticles impact on cellular processesCellular processes in plantsPlant. Nanoparticles act as catalysts to activate signaling pathways that contribute to DNA processing, post-transcriptionalPost-transcriptional regulationRegulation, gene expressionGene expression, and genetic regulationRegulation pertaining to processes associated with plant developmentPlant development, growth, and stress toleranceStress tolerance. The toxic effects resulting from treatment with nanoparticles were also mentioned, which are related to membrane damage, oxidation of lipidsLipids and proteins, DNA damage, cellular componentCellular components leakage, and cellCell death. In addition, the defense systems possessed by plantsPlant from enzymaticEnzymatic andNon-enzymatic non-enzymaticEnzymatic elements were described.