P is for Protein

And also purchased ice cream from the ice cream man for the FIRST TIME EVER :)

But back to proteins. They are what structural genes code for. Everything that your body does is a result of proteins. That ice cream that I just ate is currently being emulsified in my belly by three proteins: bile salts, pancreatic lipase, and lipoprotein lipase. Proteins are probably one of the most important molecules in the body. Enzymes are probably the best known category of proteins. Most end with the suffix -ase, such as carboxylase, lipase, dehydrogenase. There are seven major categories of proteins, I believe. To be honest though I do not remember what they are. They all have some function in the body though, all proteins are actively doing something in your body.

Source: http://en.wikipedia.org/wiki/Protein

The above picture is myoglobin, which is a major part of blood (second only to hemoglobin). Proteins have four structures:

1. Primary
2. Secondary
3. Tertiary
4. Quaternary

The primary structure of a protein is it's amino acid sequence. The secondary structure is made up of hydrogen bonding between the amino groups in the primary structure. They can either bond to form an alpha-helix or a beta-pleated-sheet. A protein's tertiary structure is the way it folds. I like to think that this is the most important structure because if it incorrectly folds the protein will most likely not be able to do it's job, or even worse, do the wrong job. It's final structure involves interactions with other proteins. Quaternary structure is how the protein bonds with other proteins. Hemoglobin, for example, is made up of two alpha subunits and two beta subunits.

There is so much more I could say! I love proteins. They are so so so important to how our body works, it's really amazing.

Answer to Tuesday's question: A famous experiment demonstrating osmosis is the dialysis tubing experiment! You put starch and a colored substance on one side of a semipermeable dialysis tube and submerge it into water. The color will seep out of the tube but turn to a different color.

If you were to change one amino acid in the primary structure of a protein, do you think it would change the entire protein or render it useless?