Antimicrobics effective against a wide variety of microbial types are termed

A. Yeast: Yeast are single-celled fungi with relatively low resistance to physical and chemical agents. They are susceptible to heat, disinfectants, and antiseptics because they lack specialized protective structures like endospores, making them easier to control compared to more resistant microbial forms.

B. Bacterial endospores: Bacterial endospores are highly resistant, dormant structures formed by certain bacteria such as Bacillus and Clostridium species. They have a tough protective coat, low water content, and metabolic inactivity, which make them impervious to heat, radiation, desiccation, and many chemical disinfectants. Endospores can survive extreme environmental conditions for extended periods, making them the most resistant microbial form.

C. Fungal spores: Fungal spores provide some resistance to environmental stress and disinfectants, but they are significantly less resistant than bacterial endospores. Most fungal spores can be inactivated by standard sterilization techniques such as autoclaving.

D. Protozoan cysts: Protozoan cysts are protective forms that allow protozoa to survive harsh environments, including changes in pH and desiccation. While they are moderately resistant, they are not as impervious to sterilization methods as bacterial endospores.

E. Naked viruses: Naked (non-enveloped) viruses are more resistant than enveloped viruses to detergents and some disinfectants due to the absence of a lipid envelope. However, they are still more susceptible to heat, radiation, and chemical agents than bacterial endospores.

A. one phosphate, one nitrogenous base, one sugar: A nucleotide, the basic building block of nucleic acids, consists of a phosphate group, a five-carbon sugar (deoxyribose in DNA or ribose in RNA), and a single nitrogenous base (adenine, thymine, cytosine, guanine, or uracil in RNA). The phosphate forms the backbone of the nucleic acid chain, the sugar provides structural support, and the base carries the genetic information.

B. one phosphate, one nitrogenous base, two sugars: Nucleotides contain only one sugar, not two. Including two sugars would create a structure inconsistent with the polymerization and base-pairing rules of nucleic acids.

C. two phosphates, one nitrogenous base, two sugars: This composition is incorrect because a nucleotide contains one phosphate and one sugar. Two phosphates are only present in nucleoside diphosphates (like ADP), which are energy carriers, not in standard nucleotides forming DNA or RNA strands.

D. one phosphate, two nitrogenous bases, one sugar: Each nucleotide contains only one nitrogenous base. Having two bases would disrupt proper base pairing and the linear structure required for DNA and RNA strands.