Biology / Unit 2 Bio 0269 short lesson, about 20 seconds
Ribosomes
Captions available
The idea
A ribosome, built of large and small protein-RNA subunits, carries out protein synthesis by translating mRNA into a sequence of amino acids.
In practice
Ribosomes float free in the cytoplasm or attach to the plasma membrane or ER, densest in cells that secrete heavily.
Where people slip
A ribosome is not membrane-bound — it is a molecular complex, present in prokaryotes and eukaryotes alike.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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