SCIENCE
CELL BIOLOGY
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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ribosome
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cytoplasm
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nucleoid
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Plasma membrane
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Detailed explanation-1: -The DNA in prokaryotes is contained in a central area of the cell called the nucleoid, which is not surrounded by a nuclear membrane. Many prokaryotes also carry small, circular DNA molecules called plasmids, which are distinct from the chromosomal DNA and can provide genetic advantages in specific environments.
Detailed explanation-2: -Prokaryotic cells, such as bacteria, have a free-floating chromosome that is usually circular and is not enclosed in a nuclear membrane. Instead, the DNA simply exists in a region of the cell called the nucleoid.
Detailed explanation-3: -The nucleoid (meaning nucleus-like) is an irregularly shaped region within the prokaryotic cell that contains all or most of the genetic material. The chromosome of a typical prokaryote is circular, and its length is very large compared to the cell dimensions, so it needs to be compacted in order to fit.
Detailed explanation-4: -Nucleoid is also known as genophore, prochromosome, incipient nucleus and chromoneme. Unlike the eukaryotic (true) cells, bacteria do not have a membrane enclosed nucleus. The chromosome, a single, continuous strand of DNA, is localized, but not contained, in a region of the cell called the nucleoid.
Detailed explanation-5: -The nucleoid contains the genomic DNA, and molecules of RNA and proteins. The main proteins of the nucleoid are: RNA polymerase, topoisomerases and the histone-like proteins: HU, H-NS (H1), H, HLP1, IHF and FIS.