Smoking...

Damn I haven't smoked all day and this just reminded me.

I think it's tar that damages the cilia, I'm not sure about the other two.

Hmm..this smells like a homework question...should you be researching this by yourself rather than getting the answers easily, if so?

http://www.wisegeek.com/how-does-smoking-affect-the-cilia.htm
*hugs* and good luck with your exam =)

what's the specific thing in a cigeratte that...
1) damages the cilia
2) destroys the fibrous elastin tissue
3) increases the number of protein eating phagocytes

any help much appreciated

1.) Broadly speaking, tar

2.) Well, it's the enzyme elastase, which is produced by phagocytes (so they can break down elastic tissue to allow them to migrate). So any particulates of any sort in cigarette smoke would attract phagocytes, and cause an increase in elastase. Also, oxidants oxidise elastase inhibitors, so their action continues for an extended period of time.

3.) Protein "eating" lol Well, elastase also degrades protein, so as above.