Thursday, 13 October 2011

5 things in Tears

The full title of this post is '5 things in tears that you had no idea because you were too busy crying like a little bitch'.  That seemed too long so I truncated it.  You can have three types of tears (basal tears -normally needed to wet the eye, reflex tears (ones needed from a foreign particles like dust or onion vapour) and psychic tears like you are doing right now.  

1. Water.  The essential liquid for life.  Water has a surface tension of 72.8 dynes allowing it to stay together in a droplet that comes off from your face after you listen to some emo band like 'My Chemical Romance' or 'Him'.  With all the other things in tears the surface tension can be lowered to 43 dynes/cm.

2. Mineral salt.  So you are crying and you taste your tears.  Salty right?  The human tears and sweat glands are evolutionary related leading some people to believe they are similar to other animal's salt gland.  Which is a gland in the tongue in animals like sharks and birds to excrete excess salt (and also why you do not see most animals crying).  If crying is good to get rid of any excess salts in your body I have no idea.  However, the tears are high in potassium which supports that theory that they may be evolutionary related to the salt.  The tears will have a similar content in sodium and potassium and even urea to the blood.

3. Antimicrobial peptides and proteins like antimicrobial peptides defensins and LL-37 work to bind and cover the bacterial membrane to create pores thus destroying it.  Phospholipase A2 is also found here that (and in snake poison) to destroy the phospholipid membrane of any foreign particles with particular phospholipids to and help to cause a inflammation reaction for more.  Phospholipase A2 is the principal bactericide for staphylococci and other gram-positive bacteria in human tears.  The activivity of this enzyme is awesome and really cool pictures can be acquired using fluorescence coupled with a monolayer device to make a small film.

4. Lysozyme is secreted in many places.  Lysozyme binds to the cell wall of the bacteria and cleaves the sugar in the cell wall destroying the gram negative bacteria. 

5. If you are under stress you might protein-based hormones, prolactin, adrenocorticotropic hormone, and leucine enkephalin (natural painkiller). These types of tears would vary greatly then if they were produced by something from  all of which are produced by our body when under stress. Some of these hormones can have The change in sex drive could be attributed to the drop in testosterone provoked by the chemicals in the tears meant to reduce aggression and may cause a crying woman to lower the sex drive in a man. In the animal world, it has been found that some blind mole rats would rub tears all over their bodies as a strategy to keep aggressive mole rats away.  So basically emo kids are probably preventing bullies from beating them up but they are also lowering their overall attractiveness.