All of the following characteristics apply to bacterial genomes except________________?
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Answer: D. Its DNA has both introns and extrons
Explanation
Bacterial genomes consist of circular DNA lacking histones and do not contain eukaryotic introns and exons. Prokaryotic genes are uninterrupted coding sequences transcribed continuously without requiring RNA splicing steps. Circular chromosomes pack efficiently into bacterial cytoplasm regions known as nucleoids without histone spools. Bacterial chromosomes are typically single, double-stranded circular DNA molecules carrying essential genetic instructions. Prokaryotes lack membrane-bound nuclei, allowing simultaneous transcription and translation of genetic messages. Plasmids are smaller extra-chromosomal circular DNA molecules frequently conferring antibiotic resistance traits.
Bacterial genetic simplicity allows rapid replication rates enabling fast adaptation to environmental pressures. Understanding prokaryotic genome organization helps scientists design targeted antibacterial drugs sparing human cells. Molecular biology research utilizes bacterial plasmids as vectors for cloning and recombinant protein production. Bacterial genomes are indeed composed of double-stranded DNA molecules as a universal biological fact. Prokaryotic DNA does not contain histone proteins, relying on different nucleoid-associated proteins instead. Bacterial chromosomes are circular molecules distinguishing them from linear eukaryotic chromosomes found in animals.
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