Thymidine kinase 1 (TK1) phosphorylates thymidine nucleosides to generate thymidine monophosphate. This reaction belongs to the pyrimidine salvage route that is phylogenetically conserved. In the model plant Arabidopsis thaliana. TK activity contributes to maintain nuclear and organellar genome integrity by providing deoxythymidine-triphosphate (dTTP) for DNA synthesis. https://www.roneverhart.com/Apple-11-inch-iPad-Pro-Wi-Fi-64GB-Space-Gray-2018-release/