Mitochondria are essential organelles in eukaryotic cells, involved in energy production, metabolism, calcium regulation, apoptosis, and immunity. They have their own genome (mtDNA) and are inherited maternally, which imposes unique challenges on their segregation during cell division, development, and disease. Mitochondrial dynamics, including fusion and fission, are crucial for maintaining mitochondrial structure and function. These processes, along with organelle transport, mitophagy, and genetic selection, ensure the proper segregation of mitochondria and their DNA during cell division, oogenesis, fertilization, and tissue development. Defects in these processes can lead to cell and tissue pathologies, including mitochondrial encephalomyopathies, which are characterized by reduced mitochondrial function and clinical signs in high-energy tissues. Mitochondrial inheritance is tightly regulated, with a genetic bottleneck during oogenesis that reduces the number of mtDNA molecules in the mature egg. This bottleneck, combined with selective elimination of dysfunctional mitochondria, ensures the transmission of a functional mitochondrial population to offspring. Additionally, during early embryogenesis, there is another bottleneck that further reduces mtDNA copy numbers, leading to a tendency toward homoplasmy in somatic cells. The maternal inheritance of mitochondria is a key feature of eukaryotic cells, and recent studies suggest that this uniparental inheritance may be advantageous for promoting homoplasmy and avoiding harmful phenotypes in offspring. However, the molecular mechanisms underlying these processes remain unclear, and further research is needed to fully understand the physiological impact of mitochondrial dynamics and inheritance.Mitochondria are essential organelles in eukaryotic cells, involved in energy production, metabolism, calcium regulation, apoptosis, and immunity. They have their own genome (mtDNA) and are inherited maternally, which imposes unique challenges on their segregation during cell division, development, and disease. Mitochondrial dynamics, including fusion and fission, are crucial for maintaining mitochondrial structure and function. These processes, along with organelle transport, mitophagy, and genetic selection, ensure the proper segregation of mitochondria and their DNA during cell division, oogenesis, fertilization, and tissue development. Defects in these processes can lead to cell and tissue pathologies, including mitochondrial encephalomyopathies, which are characterized by reduced mitochondrial function and clinical signs in high-energy tissues. Mitochondrial inheritance is tightly regulated, with a genetic bottleneck during oogenesis that reduces the number of mtDNA molecules in the mature egg. This bottleneck, combined with selective elimination of dysfunctional mitochondria, ensures the transmission of a functional mitochondrial population to offspring. Additionally, during early embryogenesis, there is another bottleneck that further reduces mtDNA copy numbers, leading to a tendency toward homoplasmy in somatic cells. The maternal inheritance of mitochondria is a key feature of eukaryotic cells, and recent studies suggest that this uniparental inheritance may be advantageous for promoting homoplasmy and avoiding harmful phenotypes in offspring. However, the molecular mechanisms underlying these processes remain unclear, and further research is needed to fully understand the physiological impact of mitochondrial dynamics and inheritance.