Most Human-Infecting Viruses Are Maintained in the Human Population Only

question 27

Multiple Choice

Most human-infecting viruses are maintained in the human population only. However, a zoonosis is a disease that is transmitted from other vertebrates to humans, at least sporadically, without requiring viral mutation. Which of the following is the best example of a zoonosis?

• A) rabies
• B) herpesvirus
• C) smallpox
• D) HIV
• E) hepatitis virus

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Definitions:

Heterochromatin

Highly coiled and compacted chromatin in an inactive state. Compare with euchromatin.

Transcriptionally Inactive

Referring to genes or DNA regions that are not being transcribed into RNA, often due to regulatory mechanisms.

Chromatin

The complex of DNA and proteins, primarily histones, that forms the chromosomes within the nucleus of eukaryotic cells.

Homochromatin

Incorrect term, possibly meant to refer to Heterochromatin or Euchromatin, which are forms of chromatin in the genome. NO.