Diseases threaten homeostasis by disrupting the normal functioning of the body. The main causes of disease include pathogens, inherited disorders, exposure to toxins, poor nutrition, organ malfunctions, and high-risk behaviors. Pathogens that cause disease include bacteria, viruses, fungi, and parasites. Cancer is an example of a genetic disease caused by uncontrolled cell division due to genetic mutations, which can be caused by exposure to chemicals and radiation.

1. Topic: Disease as
failur e of
homeostasis.
Aim: How do diseases threaten
homeostasis?
Do now: Define these terms,
Disease, pathogen. Give examples

2. What are the causes of
disease?
 Copy table 2-3.
 Causes of disease are:
 Pathogens
 Inherited disorders
 Exposure to toxins
 Poor nutrition
 Organ malfunction
 High risk behavior.

3. What are the
pathogens that cause
disease?
 Study table 2-4
 Name a pathogen, describe it & give an
example of a disease caused by it.
 Read about Cancer & Ans.
 What is cancer?
 Cancer is uncontrolled cell division due to
genetic mutation (genetic change) in a cell.
 What are the causes of gene mutations?
 Exposure of cells to certain chemicals &
radiation increases mutations.

4. How does the body
protect itself against
disease?
 Waiting for you answers!