Single-celled farmers

While we normally think of single-celled organisms as pond scum, scientists recently published a paper showing that amoebae, single celled eukaryotes, can be social and look out for the good of their populations. When they are running low on the bacteria they eat, the amoebae band together with the last few bacteria into a balloon-like structure, which floats away in the wind. When they land, they "plant" their bacteria in the new area which hopefully has more food for them. In this way, the amoebae can spread to a new location and take their food along with them. I thought this was a very impressive feat for a single-celled organism; you can read more at Scientific American: http://www.scientificamerican.com/article.cfm?id=amoeba-animal-farmers

Another fascinating study, published this month in the journal Science, indicates that people who write down their anxieties for a few minutes before a test can up their scores by about 5%, especially those who are normally prone to test anxiety. Might want to consider this strategy before your next exam! Link: http://www.boingboing.net/2011/01/20/relieving-test-anxie.html

Sleep

For the past week or so, I've been wondering what it is about sleep that dulls one's instincts. Why is it that I am able to suppress the urge to cough or go to the bathroom while sleeping, when as soon as I wake up I become strongly aware of them? Does something happen while I sleep that blocks receptors which would normally send signals to my brain, making me aware of my body? Also, what distinguishes sleep from simple unconsciousness or a coma, making it possible for me to wake up after a number of hours?

I've been researching this topic lightly on wikipedia, and concluded that I need to know more about adenosine. Adenosine is the combination of Adenine (one of the nitrogenous bases in DNA) and a ribose sugar (so it's like a nucleotide without the phosphate group). Apparently, adenosine is a neurotransmitter that builds up in the body over the course of a day, and high concentrations of adenosine make people sleepy. In addition, caffeine can bind to some of the same receptors as adenosine, acting as an inhibitor that blocks adenosine from binding to the receptor. I had read that caffeine allows people to maintain their current state of wakefulness, so that instead of getting drowsier it keeps you at the same state of sleepiness. This makes sense, if it is keeping the adenosine that continues building up in your body from acting on your receptors and making you sleepy.

Sleep also is promoted by the release of the hormone melatonin, which is only produced when it's dark, and how long you need to sleep to feel rested is partially genetic (at least one gene that regulates this has been discovered). I am still trying to find out exactly what causes me to be unaware of my senses during sleep - a quick google search didn't give me any answers so I'll have to go more in depth. It's funny to me, though, that every time I look for an answer to a scientific question, I always find new information that makes me want to ask more questions.

Biology Class Blog

Hello, and welcome to the class blog for Biology 160. Since you have to write a biology blog, I decided that it's only fair if I write one too. I will be posting periodically with interesting new things I am learning about biology. Since we're just beginning the class, I thought I'd post some information about me.

While growing up, my father was in the Air Force, so I have lived in many different areas of the United States. I went to high school in Portland, Oregon, did my bachelor's degree at Utah State University, and received my master's degree at Washington State University in Pullman. I love teaching, but am also a big fan of science research. While at Utah State, I had the amazing opportunity to go to Puerto Rico for a summer research project, where I studied large freshwater shrimp, Macrobrachium carcinus. These shrimp are often a foot long, and the largest one ever found was 22 inches! They lay their eggs in streams, and the eggs wash down to estuaries near the ocean. As the shrimp hatch and grow, they migrate upstream, crawling over waterfalls on the wet rocks to get to high mountain pools where fish cannot hunt them. My study involved trapping and tagging these shrimp to see whether the adults were still migrating.

For my master's degree, I studied the invasive New Zealand Mud Snail, which has invaded many streams and rivers in the US, including areas of Yellowstone National Park, the Columbia River, and Lake Tahoe. Just over a year ago it was found in Capitol Lake in Olympia. These snails can reach densities of over 100,000 snails per square meter, and eat so much that they crowd out beneficial species and insects that provide food for fish. Their populations grow very quickly because they can reproduce asexually, so only one snail is required to start a new invasion.

Whether or not you plan to do research as part of your career, it is important for you to understand how science works and where our knowledge comes from, so we will be doing some research of our own for this class. Last quarter my students did some fantastic projects, and I'm looking forward to seeing what you come up with this quarter!