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Introduction to the lesson
Having studied infectious diseases, we will now look at the defence systems within the body which combat infection. It has been estimated that one million pathogens enter your body every day. Why is it that, with so many pathogens entering the body, you are not constantly sick? The answer is that the body is designed to defend itself. The immune system ensures that most of the pathogens that enter your system are destroyed before they have any effect.
Preparing for the chapter
- What do you think is meant by the term “immunity”?
- What forms part of the immune system?
- How do you think the body can be protected from further infection by the same pathogen?
- Why do you think the blood is a suitable medium for carrying cells involved in immunity?
First reading of the chapter
Skim through the chapter quickly (as explained in chapter one).
Second reading of the chapter
Now read the chapter in more detail. It is not necessary to take notes as you will work through each section in detail in the following lessons.
Closing
As you end this lesson, ask yourself
- What new things have I learned today?
- What did I already know?
- What still confuses me?
NOTE: This chapter covers section 11 of the Cambridge International AS Biology (9700) syllabus 2016-2018 (p.30).