Eukaryotic cell Prokaryotic cell
Nucleus - present - no nucleus, nuclear envelope and nucleolus
Mitrochondria - present - absent
Chloroplast - present in plant only - never present
Endoplasmic reticulum - present - absent
cell wall - present in plant only - present but made of murein
chromosome - DNA - circular DNA
ribosomes - large - small
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Endosymbiotic development of eukaryotic cells
It is thought that mitochondria and chloroplasts were once prokaryotic cells that invaded eukaryotic cells.
This is symbiotic because both benefit. The eukaryotes provides nutrients to prokaryotes while prokaryotes provide metabolic reaction such respiration and photosynthesis for eukaryotes.
Evidence to support the theory:
- Inner membrane of chloroplast and mitochondria similar to prokaryotes and the outer membrane similar to eukaryotes
- both chloroplasts and mitochondria have a small piece of circular DNA with no nucleus enclosing it
- ribosomes in both chloroplasts and mitochondria are same size as prokaryotes
- chloroplasts and mitochondria reproduce by binary fission as prokaryotes do
- both chloroplasts and mitochondria similar in size to prokaryotes
