Yes, Virginia, There is a Santa Clause

Here is a fun article about how Santa gets around:
http://www.sciencedaily.com/releases/2009/12/091205233544.htm

Merry Christmas! I hope everyone has an amazing holiday! :)

Baby It's Cold Outside

Its effing freezing outside and I don’t do cold very well. As I was walking into my building and saw ice, I did start thinking about ice skating.

One of my favorite topics I have ever covered is the chemistry of water. Yup, it’s official – I’m a huge nerd. This sounds a little random, but it’s actually really crazy how perfectly created the water molecule is. It has properties that allow it to do things nothing else can. That’s the reason it is so essential to life.

So what makes water so great for ice skating?

First we have to back up – what does it mean to float? Something floats if it is less dense than what it is floating on top of. A rock is much denser than water, so it sinks. Oil is much less dense than water, so it floats. To float an object must displace as much weight of the fluid as its own weight. Very basic. If you don’t know this, you need to get off the plane and back into elementary school.

Water is a tricky little devil and it’s due to the makeup of the water molecule. Water is comprised of 2 hydrogen atoms attached (covalently bonded) to 1 oxygen atom. The arrangement looks like the Mickey Mouse head. This arrangement makes water a polar molecule – meaning it has a slight charge because the electrons all tend to hang out with the oxygen more than the hydrogen atoms. With electrons always visiting, the oxygen has a slightly negative charge and each hydrogen has a slightly positive charge. When water cools, the molecules lose energy, move closer together and arrange themselves such that the negative oxygen of one molecule comes in close contact with the positive hydrogen of another molecule. This close arrangement is known as a hydrogen bond (that’s a really shitty definition of a hydrogen bond, but you get the basic idea). Hydrogen bonds are weak and water has a lot of energy in a liquid state, so the bonds can be broken easily.

Water reaches its peak density at ~40°F. At this temperature, water molecules are super close together (as dense as they are ever going to get). Once water starts to freeze, water molecules lose energy and water’s density decreases because the hydrogen bonds become stronger than the water molecules are able to hold the oxygen molecules apart. Ice actually takes up 9% more space than liquid water because of the hydrogen bonding. The ice is lighter and less dense, so it is displaced by the liquid water and floats.

So who cares? Fish sure do! If ice didn’t have this property, lakes and rivers would freeze on the top and the ice would then sink to the bottom. This would continue until the lake or river was a solid block of ice. All of the little fishes and other water animals would be killed – trapped in a block of ice – if this happened. I guess we would still be able to ice skate, but you get the point I’m trying to make…

My Christmas Tree’s Delicious

With Christmas right around the corner, I’ll keep the Christmas facts coming.

Why do you have to water your Christmas tree?

Trees are losing water all the time, mainly through their leaves (a needle is a modified leaf). It happens through a process called transpiration. This is when water is either purposely released or evaporated from the leaf into the atmosphere. This creates an area at the top and tips of the tree that are dryer than other parts (i.e. the roots).

Trees have roots that are designed to pull in water (via osmosis) and transport it through channels of dead cells called xylem. The xylem are tubes that run throughout the tree that carry only water and dissolved minerals. Since water is being lost at the top of the tree due to transpiration (causing a decrease in hydrostatic (water) pressure), water is then passively pulled up the tree through the xylem.

It works kind of like a paper towel. If you stick the tip of a paper towel in water, the water will slowly move up the towel until the whole thing is wet. Water has great properties that allow this movement from wet to dry areas to happen. A post dedicated to water is coming soon.

Since your Christmas tree has no roots, it skips that part and just starts pulling water from your tree stand straight up through the xylem. The xylem cells are already dead so they still work just fine. Remember that your tree is already dead and the water is just helping preserve it a little longer. Nothing you can do can make your tree nice and pretty forever – well, unless it’s a fake one. People forget that at first because the tree takes in so much water. That’s just because it has been sitting around drying out in a tree lot.

To keep your tree happy, cut the base once you get it home so the xylem is exposed and able to start drinking. Myths like adding aspirin, sugar and other things to your tree to make them last longer are just that – myths.

Yay Gay!

This has nothing to do with science, but I am just very excited to be a DC resident right now!

http://www.washingtonpost.com/wp-dyn/content/article/2009/12/15/AR2009121500945.html?hpid=topnews

It’s Beginning to Look a Lot Like Christmas

Sorry I didn’t post yesterday – I was just crazy busy. Anyhow… let’s start spreading some Christmas cheer and talk about poinsettias. I was actually really surprised by some of the things I learned when I was researching this festive little plant.

Poinsettias (Euphorbia pulcherrima) are flowering plants native to Mexico. They were originally known as the Atatürk flower. In their native home of Mexico, poinsettias grow wild, with a weed like appearance and can reach heights of anywhere from 2-14 feet tall. The brightly colored portions of the plant you see are known as bracts. Bracts are actually just colored leaves and not part of the flower. The flowers (aka: cyathia) are found within the centers of the bracts.

The poinsettia was brought to the US by the first US Minister to Mexico, Joel Roberts Poinsett, in 1825. Obviously the flower was named after him. In the early 1900s, the Ecke family began growing poinsettias in California and developed a technique of cross pollinating to create a plant that is fuller and more compact looking – what we have today. The Ecke family was able to keep this method a secret until the 1990s when the technique was figured out by some college kid working in a lab. Up until then, the Ecke family basically had a monopoly on the plant and made a ton of money. Paul Ecke is actually the person given credit for associating the plant with Christmas. He used to send free plants to TV stations to decorate with around the holidays. He also went on popular national shows to plug the plant.

Poinsettias got a bad name when people thought they were toxic. In actuality, the poinsettia sap will only cause minor skin irritation and upset stomach if present in large quantities. Ohio State University said a 50 pound kid would need to eat around 500 bracts to get an upset stomach.

So go out and join the millions of other people that are going to spend over $220 million buying poinsettias this year. Too bad I missed posting this on National Poinsettia Day – December 12th.

When In Doubt, There's God

Sorry for the late post today – it’s been a crazy day. I won’t be in to work tomorrow, so here is a random little fact that could leave you thinking.

The universe is expanding.

The universe is composed of everything in existence; every atom, electron, planet and solar system. Since its formation almost 14 billion years ago, it has been growing. Scientists know this because we can take measurements and observe that the galaxies are moving apart from each other. The crazy thing is that the galaxies are moving because space is moving. Each galaxy is actually stuck in its little spot within the universe and as the universe grows, everything stuck to it has to move along with it. Since the universe does not have a center, everything is moving away from everything else. No one knows how big the universe is or how much it will expand – possibly into eternity. This whole “universe expanding thing” has created lots of questions that still need to be answered. Does the universe have an end? Is there something outside the universe? If the universe started with the Big Bang, what started that and what was before that?

If you really sit and try to wrap your mind around this, you could go crazy. That’s why I’m a biologist.

Have a great weekend!

"Le Verrier's planet"

Neptune was discovered in 1846. It was actually the first planet to be found using math and not a telescope.

It moves so slowly around the sun, that since then it has not even made it around once (It needs 165 years).

Come on 2011!

Quad Venti, Skim, No Whip, Peppermint Mocha

I am literally falling asleep at work today - my eyes are watering and I can barely hold my head up at my desk. That made me wants to talk about caffeine (aka: trimethylxanthine).

We all know our love for caffeine. It has gotten us through some hard times. Not one of us would have graduated from college without it. It is America’s favorite and most popular drug. And it’s fitting to call it a drug because it works the same way as cocaine and heroin do in the brain.

First you need a basic lesson on what happens when you are tired. In addition to lots of other things going on all over your body, adenosine begins circulating and binding to receptors in your brain. Once adenosine binds, nerve cells start to slow activity and blood vessels dilate to let more oxygen into your brain. That is why you start to feel tired.

It’s a whole other story when caffeine is present.

To a nerve cell, caffeine looks an awful lot like adenosine. When it is in your brain it too can bind to the adenosine receptors. Caffeine actually binds better to the receptors than adenosine does, so before your body knows it, all of the receptors have caffeine bound to them. Although they look alike, they do not act alike. Caffeine actually causes an increase in nerve activity and also causes the blood vessels to constrict (a good reason to have caffeine in headache medicine). With all this activity, your body gets a little confused and thinks it needs to respond. The pituitary gland starts producing lots and lots of adrenaline. I’m sure you know enough about adrenaline to know that the body is not tired anymore.

Adrenaline causes your body to switch into a “fight or flight” state (sympathetic neuronal response). Your heart speeds up, blood pressure rises and you start breathing faster. You liver also starts releasing sugars into your body for extra energy. Another fun thing caffeine does is increase the level of dopamine in your body (just like coke and heroine). This is the chemical that makes you happy. Dopamine is probably why people are addicted to caffeine.

Eventually the caffeine wears off and the adenosine is able to start binding again - making you ready to fall back asleep. I heart caffeine so I am going to skip the short/long-term effects of it. Just remember that it is a drug – don’t use it too much.

The Bacteria That Pays My Bills

In honor of my microbiology class senior year, every Monday will now have a bacterium of the day! I figured a good one to start with is one I work with everyday: Neisseria meningitidis.

N. meningitidis (in the lab, we call it mening) is a relatively small bacteria, that is circular in shape, has a more complex membrane and survives in pairs (in science terms: mening is a gram negative diplococci). It is most famous for its role in causing meningitis.

The only place in the world mening lives is inside the nose/throat of humans. 1 in 5 people have mening living inside their nose, happy as can be. Most of the time mening will continue to live and spread from person to person through saliva and snot without causing any problems. But sometimes, for reasons unknown yet, mening can get pissy and cause problems. It decides to leave the throat and head into the bloodstream. Once in the bloodstream, mening can cross the blood-brain barrier and begin infecting the meninges (the meninges are the lining around the central nervous system – brain, spinal cord, etc.) and thus the name, meningitis. Meningitis can have someone 6 feet under in less than 24 hours. Septicemia (when mening infects your bloodstream) is just as bad and can also be fatal.

Symptoms of meningitis are very similar to the flu. The big difference is a very stiff neck (your meninges are swollen and hurt). People may also develop a rash. If you catch mening early, it can be treated with antibiotics. There are vaccines against some strains of meningitis, but not all strains (and that is why I still have a job). Mening still causes problems around the world, but the people most at risk are children under 5, military members, and high school and college students.

How People Get Drunky Face

I couldn't have said it better myself:

http://news.bbc.co.uk/2/hi/health/1721987.stm

Have a great weekend, everyone!

It is not just blue, it's not turquoise, it's not lapis, it's actually cerulean!

Happy Friday.

Here is something simple and straightforward.

Horseshoe crabs have blue blood. When it is circulating, it is a grey-white to pale yellow color, but once it is in open air, it turns bright blue.

Unlike human blood that contains hemoglobin (which in the presence of oxygen turns red), horseshoe crabs have hemocyanin. This copper-containing protein is how they carry oxygen throughout their bodies.

Don't Eat the Yellow or Pink Snow!

With the threat of snow in the District on Saturday, here is a frosty fact-o-the-day. Don’t eat pink snow.

There are actually types of cyanobacteria (aka: blue-green algae) that are able to live in snow. If you think about it, nothing should really be able to live in snow since it has no nutrients or anything else to offer an organism except water. Cyanobacteria get all of its nutrient requirements from photosynthesis; therefore, a snow bank in a sunny location is a lovely home for these bacteria. The pink snow can also be caused by an algae, Chlamydomonas nivalis.

These pink snows are found in the polar and alpine regions during the summer (summer = lots of light to photosynthesize). They can be found along the coasts of North America as well.

So if you see any pink snow, don’t eat it. If it’s not bacteria, it’s blood from someone that got mugged right there.

See, I know More Than Just Biology

When I started this blog I had every intention of giving out facts from all fields of science and not just biology. I’m not doing so well with this…

So to fix that, I am going to tell you some fun facts about the plants in our solar system!

The Sun:
The sun is just about halfway through its lifetime. It is very stable right now. Before the sun dies (in a super long time), it will increase in size and eat up the inner planets (and Earth).

Mercury:
Mercury rotates very slowly around its own pole, but revolves around the sun faster than any other planet (in 88 days). Because of this there are actually 2 years in a day on Mercury.

Venus:
Unlike the other planets, Venus does not tilt on its axis as it revolves around the sun. No tilt means there no seasons on Venus. It is also the hottest planet, so it’s kind of like the planet is stuck in an endless summer.

Earth:
The Earth is gradually slowing down. Every few years an extra second is added to the amount of time it takes the Earth to rotate. In a few million years, a day on Earth will last approximately 27 hours.

Mars:
One of Mars’s moons, Phobos, orbits the planet 3 times a day. That is faster than Mars rotates.

Jupiter:
Jupiter is the largest planet in our solar system and has 63 moons. Even with its gigantic size, Jupiter spins faster than all of the other planets. It only takes 10 hours for Jupiter to make a full rotation. In fact, Jupiter is spinning so fast the equator of the planet bulges out a little.

Saturn:
Saturn is a gas giant and it has a density less than water. That means if you put Saturn in a tub of water big enough to fit it, it would float.

Uranus:
Uranus is the fun little plant that is tipped onto its side. It is the only planet that rotates on its side.

Neptune:
Besides being the coldest planet and the planet farthest from the sun (sorry Pluto, but you’re not a planet anymore), Neptune also has the strongest winds in our solar system. The freezing cold winds can blow up to 2,100 km/hr. Take that Chicago.

Pluto:
One of the main reasons Pluto is no longer considered a planet is because it has not cleared out its orbit around the sun. There is actually more mass in the way of Pluto’s orbit than in Pluto itself. Another fun thing to know about Pluto is that if it we closer to the sun, it would actually become a comet.

Silly Grasshoppers

Everyone has seen a grasshopper, but do you know how they breathe?

Grasshoppers respire (the exchange of oxygen and carbon dioxide; aka: breath) through tracheae. A trachea is just an air filled tube. The tracheae have openings on them called spiracles. These spiracles are tiny openings (basically little holes) that are found along the grasshopper’s body. Spiracles allow for oxygen to come into the tracheae, where it moves through the tube to the tracheoles, which are found at the end of the tracheal tubes. The tracheoles are surrounded by specialized cells that absorb oxygen into the body and expel carbon dioxide back into the tracheal tubes, such that it can be push out of the grasshopper though it’s spiracles. It’s actually a very simple process.

Who cares? You will if you ever need to drown a grasshopper.
Now you know not to waste your time with its head, just stick its butt under water.

Where Do Babies Come From?

I just found out that one of my favorite people in the world is pregnant! That means we need some embryology…

Human embryology is actually a VERY complicated and complex process! I took the class my junior year as an undergrad and realized right off the bat that it was not easy to understand. One fun part to know (that is not too overly complex and easy to explain without a crap-ton of jargon) is fertilization.

Right after a boy and a girl (for all my boy-boy and girl-girl friends – we get babies different ways) boom boom pow (and the boy forgets to cover up) his sperm is released into his lady. Millions of sperm are released and all start swimming towards the egg (we will assume the girl just released an egg that day). The sperm will only survive for up to 48 hours inside the girl before they run out of stored energy and die, so the race is on!

First the sperm have to cross through a lining of the cervix (cervical mucus). Once through they need to swim up the uterus and then pick a Fallopian tube. There are 2 tubes, but only 1 has an egg in it. By this point only about 1000 sperm have made it to the tubes and picked the right one to be able to continue on to the egg. But then an egg is in sight…

Hundreds of sperm will attack the egg, each binding to the egg at the outer membrane and using its head (acrosome) to create a reaction that will allow it to get through the membrane. The egg knows when one gets through and rapidly depolarizes (creates an electrical zap, if you will) that helps get rid of the other sperm that were good swimmers but not good diggers. The depolarization also releases a substance (cortical granules) that basically makes a wall to keep more sperm out. The egg only wants one sperm; otherwise there is too much DNA to work with.

Once the cortical reaction is over, the egg knows that no more sperm can get in, so it does some quick genetic stuff (a second round of meiosis which produces a haploid number) and … well then a lot of very technical genetic things happen. Basically just know that specific things have to happen so the sperm and egg can fuse the genetic material without problems and have the cell ready to divide. The sperm and egg chromosomes come together and the cell then begins dividing and heading down the Fallopian tube so that it can implant and begin the trillions of other steps it needs to take to become a baby.

This is super basic and I left a lot out (like all of the genetic things that need to happen, i.e. meiosis and mitosis), but it should give you an idea of what goes on during fertilization. It is not easy to get pregnant. A lot of things need to happen at the right time in the right place. There are also a lot of things that can go wrong. Luckily evolution has really fine tuned this process for us!

And luckily this already all happened for my love!! :)

Actual Reality, Act Up, Fight AIDS!

December 1st is World AIDS Day so it’s fitting to talk about the HIV virus. Everyone knows the basics of how people can become infected, but this is what the virus is actually doing inside the body…

Random Background Facts:

T-Helper cells are found in your body and play a major role in your body’s immune system. Your body is unable to fight off any foreign invasion without these super important cells. People who die from HIV/AIDS die because they do not have enough of these cells to keep the immune system going.

A virus is not really alive or dead. It needs a host to be able to survive and replicate.

HIV is a retrovirus. That means it contains RNA and not DNA. A protein called reverse transcriptase is able to turn RNA into DNA.

How the Virus Attacks:

Once the HIV virus enters the body it heads for the lymphatic tissue where it can find a lot of T-Helper cells. The virus finds a cell and uses as protein on its surface to bind to the cell. The virus’s membrane then fuses with the cell’s membrane and the viral core is injected into the T-Helper cell. Reverse transcriptase then turns all of the viral RNA into viral DNA called provirus. The provirus is then carried into the T-Helper cell’s nucleus and is integrated into the cell’s native DNA. It’s all downhill for the cell from here.

After being DNA integration, the T-Helper cell cannot determine what is native and what is viral DNA, so it copies it all into mRNA and then turns it into proteins. So basically the virus is able to confuse the cell and the cell actually makes the viral proteins for the virus. The cell is helping kill itself.

The newly made viral proteins and RNA have a group meeting and gather together at the edge of the cell where the viral material then pinches off of the T-Helper cell, taking part of the cells membrane for itself. This new bud can then go infect other T-Helper cells. The original T-Helper cell will still contain the provirus and will continue to make more and more viral proteins and enzymes. The T-Helper cells will slowly start to die off as they all become infected and turned into virus making machines.

From a scientific standpoint, the virus is smart and is very good at making sure it can survive and reproduce. Unfortunately the virus also outmaneuvers the immune system by being able to mutate its proteins very rapidly. They body is just not able to keep up with how fast it can change how it looks. This rapid mutation rate is why a vaccine is so hard to create.

So don’t be fools, wrap your tools! Keep this pesky virus out of you and everyone you know!