The immune system part 1 and 2

• Biologie
• Middelbare school
• havo
• Leerjaar 2

Welcome!

Today:

Discussing homework

Explanation about immune system

Making exercises paragraph 3.5

What are we going to learn today?

Today we will learn:

 What pathogens are.

How your body reacts to pathogens

Immune system

Your body interacts with a lot of substances that don't originate from your body itself. Your immune system check/destroys these foreign substances. 

Pathogens

Pathogens are often small organisms that infect your body. They do this because they need to eat, reproduce or defend themselves against your body. This can harm it. 

Viruses

Viruses are non-living pathogens. They are mostly just a little strand of DNA in a tiny package. Viruses use living cells to reproduce. The outside of a virus consists of antigens, which can mutate and change. 

www.rivm.nl

Our immune system

Your body possesses specialized cells that protect your from pathogens. This can be a '''border'' which protects your from everything (non-specific) or it fights specific pathogens. The most important part of your immune system are your white blood cells. 

Allergies 

Sometimes your body reacts very extremely to a substance that isn't dangerous. You get sick however because your body makes you sick.  

This is called an allergic reaction. You mucus membranes can swell up, your airways can get narrower or you get spots on your skin. Some allergies can even be deadly. Very severe allergic reactions are called anaphylactic reactions. 

Time to work!

Start with the exercises of paragraph 3.5. You only need to make exercises 2, 4, 9 en 11.  

Welcome!

Today:

Discussing homework 

Explanation about immune system

Making exercises paragraph 3.5

What are we going to learn today?

Today we will learn:

 What pathogens are.

How your body reacts to pathogens

How your body fights against pathogens 

Immune system 

Your white blood cells fight against pathogens: by encircling them or by making antibodies.

White blood cells can change their shape quite easily. That enables them to leave a capillary when a pathogen is nearby so they can encircle and kill it.  

Antigens

Every cell/virus has antigens on the outside. Those are proteins with which they can identify themselves or enter another cell. 

When the DNA of a cell changes, the antigens can also change. 

Antibodies

Antibodies are substances that can ''stick'' to the antigens of pathogens, making them clump together and harmless. 

To make fitting antibodies however, white blood cells need some time to ''study'' the pathogens and producing the suitable antibodies. 

Immunity

When your immune system has studied a pathogen, it can recognize that pathogen in the future and destroying it quicker. This results in you being immune to that pathogen. By getting sick yourself you build up natural immunity. 

Sometimes you need to be vaccinated for a pathogen. Vaccines consist of just the antigens of the pathogen so your body can still study it but you won't get sick. When you are actually infected your body can still recognize the ''new'' pathogen and destroy it quickly. This is called artificial immunity. 

To be properly protected against certain diseases every population must have a sufficient vaccination coverage. 

State vaccination program

Time to work!

Finish all exercises of paragraph 3.5. This is homework for the next lesson.

Is voedsel lichaamseigen of lichaamsvreemd?

1. Lichaamseigen
2. Lichaamsvreemd

Is het water dat in je cellen zit lichaamseigen of lichaamsvreemd?

1. Lichaamseigen
2. Lichaamsvreemd

Type ziekteverwekkers

Hoe beschermt jouw lichaam zich tegen ziekteverwekkers?