Final answer:
Most mitochondrial and chloroplast proteins are made within the mitochondrion or chloroplast itself.
Step-by-step explanation:
Most mitochondrial and chloroplast proteins are made within the mitochondrion or chloroplast itself. Mitochondria and chloroplasts are semi-autonomous organelles that have their own genetic material and ribosomes, allowing them to synthesize their own proteins. These organelles have evolved from endosymbiotic bacteria, which is why they have their own protein synthesis machinery.