SCIENCE
VIRUS AND BACTERIA
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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long thin strands
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located in the nucleus
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located in the cell wall
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not located in a nucleus
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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: -In organisms such as humans, DNA is organised into structures called chromosomes inside a nucleus, a membrane-bound compartment within each cell. Bacteria lack a nucleus, and how bacterial DNA is organised has puzzled biologists for many years.
Detailed explanation-3: -Bacteria usually have one circular chromosome of a few megabases in size. They often have plasmids whose size range from a few to one hundred or more kilobases. In some cases, the plasmids approach the size of chromosomes.
Detailed explanation-4: -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-5: -Because bacteria are prokaryotic, they do not have a nucleus and no membrane-bound organelles.