Prokaryotic cells lack:________?
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Answer: B. Nucleus
Explanation
Prokaryotic cells lack a true membrane-bound nucleus to house their chromosomal genetic material safely. Cellular organization in prokaryotes leaves their DNA localized within an unbound region known as the nucleoid. The absence of a nuclear envelope is the defining structural feature separating prokaryotes from eukaryotes. Prokaryotes include bacteria and archaea, which are microscopic single-celled organisms with simple internal layouts. Their genetic material typically consists of a single circular DNA molecule floating freely in the cytoplasm. Despite lacking a nucleus, prokaryotes efficiently perform transcription and translation simultaneously in their cytoplasm.
Microbiologists study prokaryotic cell structures to develop effective antibiotics that target bacterial ribosomes and enzymes. Understanding prokaryotes is essential for biotechnology applications like recombinant insulin production using bacteria. Prokaryotic metabolic pathways drive essential global biogeochemical cycles including nitrogen fixation and decomposition. Option A is incorrect because prokaryotes possess a functional cell membrane enclosing their cellular contents. Option B correctly identifies the missing nucleus characteristic of all prokaryotic microorganisms. Option C is incorrect because prokaryotes certainly contain a gel-like cytoplasm filled with ribosomes and enzymes.
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