Download Pre-Lesson 8: Viruses-1

Name:_______________________
Date: __________
Pre-Lesson 8: Viruses-1
Viruses are acellular (noncellular) infectious _______. (Note, if your text is earlier than the 3rd edition, you cannot easily
answer this. Instead answer: Bauman previously called viruses obligate intracellular ______________ .) Viruses lack
_______________ and _________________________________________.
Viruses are not capable of metabolic activity on their own. They cannot manufacture ___________________, ATP,
nucleic acid or anything else on their own.
They invade a cell, take control of their host ____________________ to make more molecules of viral _____________
and viral ____________________________ in order to make new viruses.
Viruses have 2 states. List them below and list the components found in each state:
Viral State
Viral Components in this state
The protein coat is called the _________________________________
What is a naked virus? ____________________________________
How does a naked virus differ from an enveloped virus? ________________________________________.
In your opinion, are viruses alive? (This is a critical thinking question; just briefly explain in a sentence or two.)
_____________________________________________________________________________________________
_____________________________________________________________________________________________.
Viral Size:
Recall from the first homework assignment, you learned that the average bacteria was ~1000nm (or 1 μm) in diameter.
Viruses are much ________, being on average smaller than ________ nm in diameter.
See Figure 13.4 of Bauman to compare the size and shape of a Red Blood Cell (RBC), E. coli, and several viruses.
RBC is ______nm, E. coli requires two measurements and is ___________ nm,
smallpox is _______ nm, and bacteriophage MS2 is _____ nm.
The largest known virus, Megavirus, is how many nm in diameter (see online unless you have the 4th ed.)________
Poliovirus is probably the smallest virus you have heard of at around _____ nm, though the smallest virus is
around ______ nm.
Viral Classification:
Hopefully you already noted that viruses vary quite a bit in their size, shape, whether they are enveloped or not,
if they have spikes, if their genome is DNA or RNA, and if the genome is single or double stranded. If not
discussed here, some of this variation will be discussed in class.
Much of this variation is used to classify viruses including their:
1. ______________________________
2. ______________________________
3. ______________________________
4. ______________________________
Because we know so little about them, viruses are not classified into kingdoms, divisions, and classes. They are
classified by viral ______________.
They are also classified by nucleic acid type into 2 families: _________________ and
_______________________. Viruses are classified into strains. A strain of a virus would be similar to races
among the human species. Strains are important, because different strains can have vastly different properties.
For example, one strain of polio virus causes the polio disease, whereas another strain of polio virus is used as a
live vaccine to prevent polio disease.
Although not mentioned by Bauman, viruses are essentially classified by the kingdom they infect. For example,
animal viruses infect ________ cells, and bacterial viruses infect __________ cells.
You may be pleased to know that viruses are not referred to by binomial Latin genus and species specific
names; instead they are referred to by their _____________ ____________ names.
Does the latter make you happy? ________