In eukaryotes most ATP production occurs in the mitochondria.
Step-by-step explanation:
Eukaryotic cells contains membrane bound organelles like nucleus, mitochondria, chloroplast, lysosomes, peroxisomes, glyoxysomes, and endoplasmic-reticulum. While mitochondria and other membranes bound organelles are absent in prokaryotic cells.
Prokaryotic cells consist of all species of unicellular bacteria whereas eukaryotes includes unicellular or multi-cellular animals and plants and fungi and protists. ATP is produced inside the mitochondria during oxidative phosphorylation though a membrane bound protein known as ATP synthase.