CELL STRUCTURES AND FUNCTION
CELL STRUCTURE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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in the nucleus alone.
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in both the nucleus and organelles.
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in the nucleoid as a single circular thread.
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in organelles alone.
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Detailed explanation-1: -Bacterial chromosomes are located in a nucleoid, a distinct cytoplasmic structure, in which double-stranded DNA is coated with histone-like proteins. Most bacteria appear to have a single large circular chromosome, but this is not universal.
Detailed explanation-2: -Most bacteria have double-stranded circular DNA as their genetic material. This circular DNA is suspended in the cytoplasm with other proteins as a distinct structure called the nucleoid. Some may have more than one circular DNA and some bacteria like Streptomyces have linear double-stranded DNA.
Detailed explanation-3: -The bacterial genome is present in the cell within a complex structure, the nucleoid. 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.
Detailed explanation-4: -Most bacteria have a haploid genome, a single chromosome consisting of a circular, double stranded DNA molecule.
Detailed explanation-5: -Prokaryotic chromosomes are found in the nucleoid of prokaryotic cells, and they are circular in shape. Unlike eukaryotic cells, prokaryotic cells don’t have a membrane-bound nucleus. Instead, their genetic material can be found in a region of the cytoplasm called the nucleoid.