An infectious protein is known to cause neurodegenerative diseases in humans such as Creutzfeldt-Jakob disease ('mad cow disease'). This type of acellular infectious agent is known as a _________.

Compare and contrast a bacterium and a virus by writing either “Present” or “Absent” for each of the following structures.

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What is the difference between a virion and a virus particle?

Viruses:

This type of acellular infectious agent is only known to infect plants and is a small, circular, single-stranded nucleic acid molecule.

Which of the following statements about acellular infectious agents is FALSE?

All of the following can be transmitted by recreational (i.e., swimming) water sources except

a. amebic dysentery.

b. cholera.

c. giardiasis.

d. hepatitis B.

e. salmonellosis.

Which of the following is not an acellular agent?

a. viroid

b. virus

c. rickettsia

d. prion

Which of the following statements is true?

a. Viruses move toward their host cells.

b. Viruses are capable of metabolism.

c. Viruses lack a cytoplasmic membrane.

d. Viruses grow in response to their environmental conditions.