Biology · Kingdom Prokaryote
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The cellular DNA of a bacterium is known as the:
- A
Plasmid
- B
Genes
- C
Chromosomes
- D
Histone
The correct answer is Plasmid. Plasmids are separate from the main chromosomal DNA and can carry genes that confer special abilities, such as antibiotic resistance, to bacteria. They are not part of the chromosomal DNA, but rather additional genetic elements. Genes refer to specific sequences within DNA that code for proteins, but they do not encompass the entire DNA content. Chromosomes form the main DNA structure in bacteria and contain all the necessary genes for basic life functions, but the question specifically asks for cellular DNA as a specific type. Histone proteins are not involved in bacterial DNA packaging, making this option incorrect.
Plasmids are small, circular DNA molecules found in bacteria that exist independently of chromosomal DNA. They often carry genes that provide advantageous traits, such as antibiotic resistance.
Genes are segments of DNA that code for proteins, but the term 'genes' does not refer to the entire DNA content within a bacterium.
Bacterial chromosomal DNA contains the essential genetic information for survival and reproduction, but it is not referred to as 'cellular DNA' in the context of additional DNA like plasmids.
Histones are proteins associated with DNA packaging in eukaryotic cells. Bacteria do not use histones to structure their DNA.
Tagged under Biology · Kingdom Prokaryote · 2017