Question

The hereditary material present in the bacterium E.coli is

• A. single-stranded DNA
• B. double-stranded DNA
• C. DNA
• D. RNA.

Answer 1

The Correct Option is B

The question pertains to identifying the type of hereditary material present in the bacterium E. coli. Let us understand and analyze the options provided to reach the correct conclusion:

1. Understanding the Types of Genetic Material:
   • Single-stranded DNA (ssDNA): Composed of a single linear chain of nucleotides. It is less stable than double-stranded DNA and is typically not found as the primary genetic material in cells.
   • Double-stranded DNA (dsDNA): Composed of two complementary strands that coil around each other, forming the familiar double helix structure. This is the common form of genetic material in most organisms, including bacteria like E. coli.
   • RNA: Often plays roles in coding, decoding, regulation, and expression of genes, but is less stable as hereditary material outside of specific viruses.
   • DNA: A generic term that does not specify the strand structure.
2. Elimination of Options:
   • Single-stranded DNA: Not typical for E. coli or most bacteria for hereditary material; hence, not the likely answer.
   • DNA: Too broad and does not specify the molecular form, which is crucial for accuracy.
   • RNA: Although crucial in protein synthesis and as genetic material in some viruses, it is not the hereditary material of E. coli.
3. Conclusion:

   Given the analysis and definitions, the hereditary material of E. coli is best described as double-stranded DNA. This option specifically identifies the molecular structure of the genetic material, aligning with the known biology of E. coli and most bacterial organisms.

Therefore, the correct answer is double-stranded DNA.