A pathogen identified in a patient's blood sample is found to lack a phospholipid bilayer. Therefore, any medications used to treat the disease caused by this pathogen would most likely be classified as:

Question

A pathogen identified in a patient's blood sample is found to lack a phospholipid bilayer.  Therefore, any medications used to treat the disease caused by this pathogen would most likely be classified as:

Quizplus · Accepted Answer

11ecba2d_1012_92a6_a3bf_3f0bc7733f9d_MD0008_00 Unlike prokaryotic and eukaryotic cells, viruses are obligate intracellular parasites that cannot reproduce outside of a host cell. The genetic material of viruses can be RNA or DNA that is double-stranded or single-stranded and is surrounded by a protective protein coat known as the capsid. In addition, viruses can be either enveloped or nonenveloped. Enveloped viruses have a membrane, or phospholipid bilayer, generally derived from the cell membrane of the host. The phospholipid bilayer of enveloped viruses surrounds the capsid and often contains host-derived proteins, allowing the virus to better evade the immune system and gain entry into the host cell. In contrast, nonenveloped (naked) viruses lack a phospholipid bilayer. In this scenario, the pathogen identified from the patient's blood sample was found to lack a phospholipid bilayer. Because all prokaryotic (eg, bacteria) and eukaryotic (eg, protozoa, fungi) cells are enclosed by a phospholipid bilayer (ie, cell membrane), the only possibility is that the pathogen lacking this bilayer is a virus (nonenveloped); therefore, it should be treated with antiviral drugs. (Choices A and B) Antifungal drugs are effective against fungi, and antiprotozoal drugs are effective against protozoa. However, protozoa and fungi are classes of eukaryotic cells (not viruses), and all eukaryotic cells have a cell membrane. As a result, an organism without a phospholipid bilayer cannot be eukaryotic, making treatment with such drugs ineffective. (Choice D) Bacteria are prokaryotic cells. Although several factors distinguish prokaryotes from eukaryotes, all prokaryotic cells are surrounded by a phospholipid bilayer (cell membrane). Therefore, the pathogen identified in the question cannot be bacterial, and antibacterial drugs would not be effective against it. Educational objective: Viruses possess DNA or RNA genomes surrounded by a protein capsid and are unable to reproduce outside of a host. Viruses can also be classified as either enveloped (have a phospholipid bilayer as the cell membrane) or nonenveloped (no phospholipid bilayer). In contrast, all prokaryotic and eukaryotic cells are enclosed by a phospholipid bilayer.

A Pathogen Identified in a Patient's Blood Sample Is Found