Biology / Unit 9 Bio 1941 short lesson, about 20 seconds
Prokaryotic Cell Structure, Reused and Extended
Captions available
The idea
A prokaryotic cell, per Bio 0067 and Bio 0249, keeps its DNA in a nucleoid and often carries extra-chromosomal DNA loops called plasmids.
In practice
A bacterium's plasmid can carry an antibiotic-resistance gene separate from its main chromosome, replicating independently alongside it.
Where people slip
A plasmid is not required for survival— it carries supplemental genes, while the main chromosome carries the genes essential to life.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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