Y3V-T2-LSN3

• Biologie
• Voortgezet speciaal onderwijs
• Leerroute 3

Welcome, please get ready:

• Pen and Paper
• Copy of the book

Disease & Immunity

Lesson 3

1st line of defence

Book page 146

Learning goals:

• I understand the difference in innate and adaptive immune system
• I understand the difference in specific and aspecific immune system
• I can explain what barriers in the human body contribute to immunity
• I can explain how each barrier contribute to immunity.

KEY WORDS:

• Innate immunity
• Adaptive immunity
• Barrier function

Innate immunesystem

• Parts of the immune system that are present from birth

Adaptive immunesystem

• Parts and processes of the immune system that are changing based on previous experiences

Lines of defence

The immune system counters attacks from pathogens in three lines of defense:

1. Barriers: keeping the pathogens out

2. Phagocytes: attacking and wiping out invaded pathogens 

3. Lymphocytes: learning from phagocytes how to specifically and effectively kill a certain type of pathogen

Lines of defence

Line 1: Barriers

• skin
• mucosal membranes
• stomach acid
• antibacterial proteins

Keeping pathogens out

Line 1: Barriers

Mechanical barriers       vs    Chemical barriers

Physical blockages preventing pathogens from entering the body

Attacking pathogens by means of antimicrobial molecules

To what part of the immune system do these lines of defence belong?

Innate immune system

Adaptive immune system

Barriers

Phagocytes

Lymphocytes

Note locations in your body that are lined by a mucosal membrane

As part of innate immunity, the human body utilises mechanical and chemical immunity Which of the following is an example of chemical immunity?

1. Skin
2. Fluid flow in the urinary tract
3. Stomach acid
4. Mucosal layer in the vagina

Explain how washing your skin with soap regularly is countering your immunity.

Homework for next lesson:

• Read page 144-145 handout or 152 book
• Make sure you master the learning goals LSN1-3
• Check the answers of homework assignment classroom