Pathogens and the Evolution of Disease

What is the concern about using antibacterial and antimicrobial soaps?

The use of any chemical that kills bacteria can eventually lead to resistance to that chemical in the population of bacteria.

How do viruses gain entry to a host cell?

by binding to a receptor site on the host cell

How do most disease-causing bacteria cause damage?

by releasing toxins

What has been suggested to promote the development of new antibiotics?

Encouraging big pharmaceutical companies to start investing again in new drug research and development.

Statements about the genome of a virus:

- The genome could be made of single-stranded DNA. - The genome could be made of single-stranded RNA. - The genome could be made of double-stranded DNA. - The genome could be made of double-stranded RNA.

What can contribute to the problem of antibiotic resistance?

- Using high doses of antibiotics in animal feed, so that we are not exposed to the bacteria. - Stopping taking the antibiotics as soon as you feel better, thereby decreasing the exposure of the bacteria to the antibiotics. - Taking antibiotics for all infections, including viral infections.

In the projected video showing the growth of bacteria, why did the bacteria grow up to the edge of the area with antibiotics, pause, then continue to grow across the area with antibiotics?

A few bacteria experienced random mutations in their DNA, which allowed some of them to grow even though antibiotics were present.

Which of the following correctly describes a "microbial cure"?

Antibiotics are used to kill all of the infectious bacteria in a person.

Over time, bacteria have become increasingly resistant to antibiotics. What best explains this in terms of natural selection?

Bacteria that happen to have natural resistance to antibiotics survived and reproduced.

A particular antibiotic kills 99% of a bacterial population. What will be the result of the continued application of this antibiotic?

Over time, the antibiotic will become less effective at killing the bacteria.

Of the events listed below, which one occurs last? - The capsid is removed. - The genome enters the host cell. - The host cell and the virus fuse. - The virus replicates.

Of the steps listed, the last to occur is viral replication.

In the example given in the tutorial, how did new viral particles exit the cell?

The RNA and proteins are assembled inside the host cell. These new viruses then bud off.

True or False. The body contains some bacteria that are helpful in outcompeting bad bacteria.

True.

True or False. Virulence is the relative ability of a pathogen to cause disease.

True.

What causes antibiotic-resistant bacteria to develop?

overuse of antibiotics

In the RNA virus (such as the one illustrated in the tutorial), what is the role of reverse transcriptase?

Reverse transcriptase copies RNA to make DNA.

When speaking of the anatomy of a virus, we can say that ________.

The genome is surrounded by a protein coat called a capsid, which may or may not be surrounded by an envelope.