Preventing Bacterial Diseases Many bacterial diseases can be prevented by stimulating the body's immune system with vaccines. A vaccine is a preparation of weakened or killed pathogens or inactivated toxins. When injected into the body, a vaccine prompts the body to produce immunity to a specific disease. Immunity is the body's ability to destroy pathogens or inactivated toxins.
Treating Bacterial Diseases A number of drugs can be used to attack a bacterial infection. These drugs include antibiotics, such as penicillin and tetracycline, that block the growth and reproduction of bacteria. Antibiotics disrupt proteins or cell processes that are specific to bacterial cells. In this way, they do not harm the host's cells.
Viral Diseases
How do viruses cause disease?
Like bacteria, viruses produce disease by disrupting the body's normal homeostasis. Figure 20–17 lists some common human diseases caused by viruses. Viruses produce serious animal and plant diseases as well.
Disease Mechanisms In many viral infections, viruses attack and destroy certain cells in the body, causing the symptoms of the associated disease. Poliovirus, for example, destroys cells in the nervous system, producing paralysis. Other viruses cause infected cells to change their patterns of growth and development, sometimes leading to cancer. Viruses cause disease by directly destroying living cells or by affecting cellular processes in ways that upset homeostasis.
FIGURE 20–17 Common Human Viral Diseases Some common viral diseases are shown in the table below. Interpret Tables Which virus can cause cancer?
dddTable of Contents
- Formulas and Equations
- Applying Formulas and Equations
- Mean, Median, and Mode
- Estimation
- Using Measurements in Calculations
- Effects of Measurement Errors
- Accuracy
- Precision
- Comparing Accuracy and Precision
- Significant Figures
- Calculating With Significant Figures
- Scientific Notation
- Calculating With Scientific Notation
- Dimensional Analysis
- Applying Dimensional Analysis