Have you recently enjoyed feelings of deep drowsiness after your Thanksgiving dinner? Well, you're not alone. And you can thank your Thanksgiving turkey as well as other components of your Thanksgiving dinner which all work together to keep you immobilized and stuck to the couch.
Turkey has a protein known as TRYPTOPHAN (pronounced "tript-O-fan"). This protein is in several other meats, but turkey itself contains a lot oftryptophan.
TRYPTOPHAN =
Everybody has hormones in their body. Hormones are chemical proteins which glands in our bodies produce for several reasons (to help us sleep, to help us feel better when we injure ourselves, or to help us grow). Tryptophan causes one's body to release hormones which in turn makes you sleepy!
The word membrane comes from the Latin word membrana meaning "a thin layer of skin or parchment".
When we're thinking of cells, both plant and animal cells have cell membranes. The cell membrane allows different substances and super-tiny particles to move in and out of the cell. The ability to allow different substances and super-tiny particles to pass through it is known as semi-permeability. The key word to remember here is permeability.
What are some things in our everyday lives that have permeability?
AIR FILTERS (this HEPA filter pulls in air and allergens like dust and moves out fresh air for us to breathe)
Our SKIN (which also has pores that allow us to move sweat out of our bodies)
This is what the inside of our skin looks like.....
And this is what the inside of a cell membrane looks like....
What are the differences?
the cell membrane has structures going from one side to the other.
the skin has a greater variety of structures than the cell membrane.
What are the similarities?
they both have channels through which different things can pass
they both have an inner layer and an outer layer
CELL MEMBRANE STRUCTURE Cell membranes have an inner layer of phospholipids and an outer layer of phospholipids. Having this two layers is called having a lipid bilayer ("bi" = "two").
CELL MEMBRANE FUNCTION Like an air filter which filters allergens or the human skin which secretes sweat to cool down the body, a cell membrane functions to allow different things in and out of the cell!
Did you see the Fantastic Four movie with the Silver Surfer? If so, do you remember the giant sinkholes which formed in the Earth? (see trailer...)
....Well, it turns out that sinkholes are a REAL geological phenomenon! Today, newspapers reported of a giant sinkhole that formed in the Earth in the tiny village of Schmalkalden, Germany.
The story of the sinkholes hit close to home as my family is from a village (see black arrow on map below) about 50 miles away from Schmalkalden (see red arrow below). What continent in Germany on? If you answered Europe, you are correct. Sinkholes have also appeared in other areas of the world, such as the one which opened up earlier this year in the South American country of Guatemala (see picture below of a sinkhole that opened up in Guatemala City). So what are sinkholes? Sinkholes are all about water. - Water dissolves minerals rocks in the earth, leaving residue and open spaces within the rock. (This is called "weathering".) - Water washes away soil and residue from voids in rocks in the earth. - Lowering levels of groundwater causes a loss of support for soft material in rock spaces which leads to collapse. - Changing groundwater gradients (due to removing or introducing water to the system) can cause loose material to flush out quicker from the voids and the surface to collapse in response. - Sinkholes can result from seasonal changes in the groundwater table, freeze and thaw of the ground, and extremes in precipitation (drought vs heavy rain).
For more on the sinkhole in Guatemala, check out National Geographic's website: http://news.nationalgeographic.com/news/2010/06/100603-science-guatemala-sinkhole-2010-humans-caused/