The modern concept of the procaryote ... Phylogenetic structure of the prokaryotic domain: the primary kingdoms. Proc Natl Acad Sci U S A 74, 5088–5090 (1977).

In addition to the nucleus, eukaryotic cells may contain several other types of organelles, which may include mitochondria, chloroplasts, the endoplasmic reticulum, the Golgi apparatus, and lysosomes.

Daniel Mills, Ludwig-Maximilians-Universität München During this time, some of the defining characteristics of modern eukaryotic cells—the nucleus, mitochondria, cytoskeleton, cell membrane, and ...

This genetic complexity mirrors modern prokaryotes, suggesting that LUCA was far from a simple organism. It likely possessed an early immune system, hinting at ancient battles with viruses ...

Scientists propose that the eukaryotic branch of this family tree formed when two prokaryotes, an ancient bacterium and archaeal cell, merged, forming a symbiotic relationship maintained over time. 1 ...