Final answer:
Mitochondria and chloroplasts can't survive outside the cell due to their long-term evolution inside host cells, where they became dependent on the cell for key functions and lost the ability to live independently.In the well-known process of endosymbiosis, host cells originally ingested these bacteria, which then became highly specialized for functions beneficial to the cell; for example, mitochondria for respiration and chloroplasts for photosynthesis
Step-by-step explanation:
Endosymbionts, such as mitochondria and chloroplasts, cannot survive outside the cell because over millions of years, they have evolved to be dependent on the host cell for protection, reproduction, and essential resources. In the well-known process of endosymbiosis, host cells originally ingested these bacteria, which then became highly specialized for functions beneficial to the cell; for example, mitochondria for respiration and chloroplasts for photosynthesis.
Both mitochondria and chloroplasts contain their own DNA and ribosomes, evidence supporting their bacterial origins, but they have also transferred many genes to the host cell nucleus, which further integrates them into the cell's biology and makes independent life impossible.