Final answer:
Approximately 1% of mitochondrial proteins are encoded by the mitochondrial genome of eukaryotic cells.
Step-by-step explanation:
The approximate percentage of mitochondrial proteins that are encoded by the mitochondrial genome of eukaryotic cells is about 1%.
Eukaryotic mitochondria contain their own circular DNA, called mtDNA, which is highly conserved. In humans, mitochondria have 5 to 10 copies of the genome, and each has 37 genes that primarily encode proteins of the electron transport chain.
However, most proteins found in mitochondria are actually encoded by genes in the nucleus of the cell. These proteins are synthesized in the cytosol and then transported into mitochondria. Thus, the majority of mitochondrial proteins are not directly encoded by the mitochondrial genome.