What's Happening to My Body When I'm Sick?

3.  Anticipatory Set

Learning Experience(s)

Show the students a set of pictures. One picture depicts an alopecia sufferer, an allergic reaction to one’s own hair follicles, one depicts a child with an anaphylactic reaction, one depicts a woman sneezing and a final depicts a woman with an inflamed forehead, an allergic reaction to hair dye.

With students, discuss that is being seen in the pictures and any similarities between them.

Approx. Time_____mins

Critical questions that will establish prior knowledge and create a need to know

1) The fourth woman’s face is swollen, what can cause swelling?

2) What is the third woman doing?

3) What do you notice about the little boy?

4) What is striking about the first photo?

5) What can you tell me about these pictures, what do they all have in common?

Expected Student

Responses/Misconceptions

1)      An inflammation immune-response.

2)      Sneezing.

3)      He has a rash, and his face looks swollen.

4)      The woman is missing patches of hair.

5)      Their immune systems are all reacting.

Checking for Understanding

 (Decision Point Assessment)

After discussing the pictures, ask students what sorts of things could cause these types of reactions. If they answer allergens, move along. If they don’t, try to lead them to it.

The assessment you will use to determine what to do next.

1)      What sort of conditions causes the immune system to react?

1)      Every year around spring time, is there anyone in the room that experiences runny noses and sneezing? Whats going on there?

2)      Is there anyone in the room that cannot eat shellfish/peanuts? What happens if you do?

3)      Is there anyone in the room that can’t have pets, dogs or cats? Why not?

4)      For either one of these, ask “What  happens if you were exposed?

What student outcome will indicate that you should move on to the exploration? What will you do if the outcome is something else?

1)      Bacterial infections, viral infections, other microbes, but most importantly for this lesson, allergens.

4) Hopefully an answer consisting of symptoms similar to the pictures will be report, making a link between allergies.

4.  Teaching

Learning Experience(s)

So many of us have allergies, myself included. Sometimes when I work outside doing yardwork, I’ll start sneezing, and all of a sudden I get a lot of sinus congestion and teary eyed. Today we’re going to look a little deeper into what causes these reactions, how they work, and why.

So what causes all of our allergies? In a single word: proteins.

So the majority of the reason why some people have allergies, and others don’t is because of their genes. So if you have bad allergies, you can blame your parents. <haha>

So the main purpose behind these two different kinds of lymphocytes then, is to protect the body. Every cell in your body has special tags that the lymphocytes read as ‘self’ and what they are programmed to do is to identify anything not labeled ‘self’ and initiate a pathway against it.

So when a person’s body encounters something that the body is allergic to, the lymphocytes identify it as a foreign invader.

Once the B-cell produces the antibodies, the allergen then becomes the antigen. The B-cell now produces antibodies specifically against this allergen. Specifically for allergic responses, the antibody is called IgE, or immunoglobulin E. This is where your genes come in to play. In a person with a properly functioning immune system, the lymphocytes are programmed to be able to distinguish between threatening and non-threatening proteins. So in the case of someone allergic, their lymphocytes can’t recognize those harmless proteins as harmless, and instead thinks that those proteins are trying to invade the body, and mounts an attack against them.

So in a person who isn’t allergic, the B-cell lymphocytes won’t create the antibodies against the proteins, but in someone extremely allergic, the B-cells produce a huge quantity of antibodies against the protein, ready to attack at the first sign.

So once the body has antibodies against an allergen/protein, and is exposed to it again, those antibodies attach to the protein and trigger the release of histamine.

Histamine has different reactions depending on where it is activated.

<show image of body with different reactions to allergens>

So now that we have learned about a different aspect of the immune system, the allergic response,  we want you guys to split into groups of three, and create a diagram showing the similarities and differences between a proper immune response to a bacteria or virus, and to an allergen. A venn-diagram will work well for this. Place the allergic response on one side, and a viral/bacterial/fungal response on the other side. Give abbreviated points to each of them in how the pathways work distinctly as well as overlapping portions of the pathways.

<teacher will go around checking the student’s understanding of the material, helping with any continued misconceptions.>

<Once 5 minutes or so has passed, or the majority of the students have items listed for each of the sections, have a venn diagram drawn out on the board, and start having the students call out items that belong under each category, briefly discussing them, and seeing if other students have questions or difficulties with what the other classmates have said. >

Approx. Time_____mins

Critical questions that will allow you to decide whether students understand or are able to carry out the assigned task (formative)

      So what three things are we going to look at today?

What are proteins?

Is there just one protein that causes allergies?

Where do these allergies come from?

Is everyone exposed to these proteins?

Then why doesn’t everyone have these reactions?

How many of you remember what a lymphocyte is?

What does this sound like? What pathway is this mimicking?

Once the B-cells identify the allergen, what does it produce?

How could this explain the fact that some people get a more serious reaction the second time they are exposed to an allergen?

What does histamine do?

What would happen if it were activated in the mouth, say by food allergies? In the stomach?

What if you touched something allergic, or were stung by an insect you were extremely allergic to?

How about if you just breathed in some pollen or mold that you were allergic to? What area would react?

Expected Student Responses/Misconceptions

What, how, why – allergies

Complex molecules shaped into different structures

No, there are many different kinds

From whatever is initiating the allergic response – the pollen, nuts, grass, etc.

Yes

People react differently, have different symptoms, etc.

It is a white blood cell, two different kinds, B- and T-, they float around in the blood and act against foreign substances.

The immune system, reaction against a bacteria or virus or fungi.

Antibodies

Antibodies already there that identify the allergen, so the reaction is more instaneous.

Causes all the symptoms of an allergic response

Swelling and itching of the lips and tongue, stomach cramps, vomiting, and diarrhea

Hives, rash, itchy

Wheezing, coughing, choking