Question

9. Explain the missing steps (steps 2, 4, and 6) in the spread of a virus from the figure shown below. (3 points)

Answer 1

Okay, so this is where we are:

Step 1: Virus attaches to host cell. (We call this "adsorption.")

~~~~~~~~~~~~~

Okay, now we're onto Step 2.

AFTER the virus attaches itself onto a cell,
it gets inside the cell.
We call this PENETRATION, because the virus penetrates the cell membrane,
and gets inside the cell.

And after it gets inside the cell,
the virus goes through UNCOATING.

You see, every virus has at least two main parts:

1. Genetic material (Like DNA, or RNA)
2. Protein coat.

The PROTEIN COAT is what protects the virus's genetic material.

After the virus gets into the cell,
the protein coat breaks down,
and releases the genetic material.

THAT is what we call UNCOATING.

~~~~~~~~~

Okay, so take a look at Step 3:
"The cell makes viral hereditary materials, and proteins."
(We call this "synthesis.")

But BEFORE Step 3, remember,
the virus needs to do two things:

It needs to PENETRATE the cell,
and UNCOAT its genetic material.
Okay?
THAT is Step 2.

~~~~~~~~~~~~~~

Okay, so let's repeat this again, real quick:

Step 1: Adsorption
Step 2: Penetration and Uncoating
Step 3: Synthesis

Okay, so during Step 3,
the virus uses the cell, in order to make copies of bits and pieces of itself.

Think about viruses like this:
they're like little toys,
made of small Lego pieces.

After the cell makes copies of the little bits and pieces of the virus,
it needs to put itself back together, you see?

All the little pieces need to come together,
and be built into actual viruses.
THIS is Step 4.

During Step 4,
the pieces of the virus need to rebuild themselves, into whole viruses.

And we call this step ASSEMBLY.

~~~~~~~~~~~~~~~~~

Okay, so now we're onto Step 5.

The virus has already assembled itself.
It has already rebuilt the little pieces of itself, in order to form a ton of new viruses.

During Step 5,
the cell explodes,
so that the viruses can be released.

(We call this LYSIS.)

~~~~~~~~~~~~~~~~~~

So now, we're onto Step 6.

At this point, remember,
the viruses have already been released.

So what do they do now?

They infect other cells, of course!

Remember Step 1?
Step 1 was called ADSORPTION,
where the virus attaches itself to a cell.

Well, Step 6 is basically just a REPEAT of all the steps,
starting again with Step 1.

The new viruses will find new cells, in order to infect.