by Miller & Levine

[complete Table of Contents]

Use the pull-down menu to jump to any of the Book's 40 Chapters:

Additional Resources:

A page of information from various sources about this bacterium and how it infects human cells

An Issues Feature for Chapter 19 describes the pros and cons of mass vaccinations against this virus.

Infectious Disease
The Center for Infectious Disease Research & Policy at the University of Minnesota.


Chapter 19
Bacteria & Viruses

NEW: Updated Information on Mad Cow Disease, two brand-new "Virtual Textbook" pages for teaching about mad cow disease (BSE) and its human equivalent (CJD). Also a new essay by Joe Levine: "The Brain Eaters."

NEW: Bird Flu? Flu Vaccine? How does the flu keep us guessing every year? "What's up with the Flu?" ( a new teaching and learning resource)

Hot Links

Chapter Self-Test

Take it to the Net Teaching Links

What are Web Codes?

Web Codes for Chapter 19:
Active Art: Virus Reproduction

Active Art: Virus Reproduction
Miller & Levine: Smallpox Vaccination
Science News: Bacteria and Viruses
SciLinks: Bacteria
SciLinks: Lytic Cycle


Section 19-1: Prokaryotes
Archaebacteria lack peptidoglycan, a carbohydrate found in the cell walls of eubacteria, and their membrane lipids are quite different. Also, the DNA sequences of key archaebacterial genes are more like those of eukaryotes than eubacteria.
Prokaryotes are identified by their shapes, the chemical natures of their cell walls, the ways they move, and the ways they obtain energy.

Section 19-2: Bacteria in Nature
Bacteria are vital to maintaining the living world. Some are producers that capture energy by photosynthesis. Others help to break down the nutrients in dead matter and the atmosphere, allowing other organisms to use the nutrients.
Bacteria cause disease in one of two general ways. Some damage the tissues of the infected organism directly by breaking them down for food. Other bacteria release toxins (poisons) that harm the body.

Section 19-3: Viruses
A typical virus is composed of a core of either DNA or RNA surrounded by a protein coat.
In a lytic infection, a virus enters a cell, makes copies of itself, and causes the cell to burst.
In a lysogenic infection, a virus embeds its genome into the DNA of the host cell and is replicated along with the host cell's DNA.

Click Here for an EM of a smallpox virus-infected cell (from the CDC)

Click Here for an EM of a smallpox virus
(from the CDC)

SARS - Severe Acute Respiratory Syndrome.
A web page with the latest information about this new health threat.

Click Here for Science News articles
on Bacteria & Viruses

[Complete Index of Articles]

Return to BIOLOGY Home Page