Complex sentence: Eukaryotic ribosomes are somewhat larger and more complex than prokaryotic ribosomes, and are 80S, being composed of a large subunit (LSU) 60S and small subunit (SSU) (40S).
Split into simpler sentences: Eukaryotic ribosomes are somewhat larger and more complex than prokaryotic ribosomes. The overall rRNA 80S structure is composed of a large subunit (LSU) 60S and small subunit (SSU) (40S).