Biologists suspect that endosymbiosis gave rise to mitochondria before plastids partly because
A) the products of photosynthesis could not be metabolized without mitochondrial enzymes.
B) all eukaryotes have mitochondria (or their remnants), whereas many eukaryotes do not have plastids.
C) mitochondrial DNA is less similar to prokaryotic DNA than is plastid DNA.
D) without mitochondrial CO2 production, photosynthesis could not occur.
E) mitochondrial proteins are synthesized on cytosolic ribosomes, whereas plastids utilize their own ribosomes.
Cell showing nucleoids within mitochondria
Endosymbiosis in Action
Alexander Fleming photographed in his lab where he observed the natural competition between a fungus
Sunlight shining through clouds, giving rise to crepuscular rays.
Will the sun rise tomorrow? Are you sure? “Cause and effect” vs. sense experience.
Mitochondria