Journal Article Research Support, U.S. Gov't, Non-P.H.S. 1406-65-1 2V16EO95H1 9KJL21T0QJ Biochemistry Chlorophyll Chlorophyll fluorescence Fatty Acids Fatty acid saturation Gossypium hirsutum Leaf expansion Linoleic Acid Palmitic Acid Photosynthetic thermotolerance Photosystem II Protein Complex Research Support, Non-U.S. Gov't Review chemical imaging desorption ionization mass spectrometry (DESI) mass spectrometry imaging (MSI) matrix-assisted laser desorption/ionization (MALDI) metabolism metabolome primary metabolism spatial maps specialized metabolism