Sunday, May 1, 2011
There are two major players when it comes to blood typing: antigens and antibodies. Antigens reside on the surface of the blood cell and are of three possible types: antigen A, antigen B, and Rh antigen. Antibodies are present in the blood plasma and appear in the first part of a persons life in response to environmental factors. There are two types of these immunoglobins: Anti-A and Anti-B antibodies.
Friday, April 29, 2011
Cyanobacteria. These are the tiny toxic man killers I am talking about.
Thursday, April 28, 2011
Sunday, April 24, 2011
So why are angiosperms and their life cycle important? Angiosperms make up 90% of living plant species. The two major characteristics of an angiosperm are the flower and the fruit, which play a critical role in the life cycle of the plant. The flower is necessary for sexual reproduction. The angiosperms rely on pollinators, such as insects, to transfer the pollen from flower to flower. The organs within the flower are the sepals, petals, stamens, and carpels. The bright color of the flower petals are an adaption necessary for attracting pollinators. The fruit is used to protect the seeds and help in dispersing the mature seeds. Some angiosperm fruits are not conventionally recognized as a fruit. In maples and dandelions, the fruits have adapted with propellers or parachutes to enhance the movement of the seeds by wind dispersion.
The angiosperm life cycle appears complex and has many characteristic attributes. The haploid part of the cycle begins with the production of the male and female gametophytes. The male gametophyte has two haploid cells that form the tube cell and two sperm. The female gametophyte consists of an embryo sac that holds the egg. After pollution, the sperm are discharged into the ovule. The fertilization signals that transition from a haploid to a diploid stage of the cycle. Angiosperms have double fertilization, which means that one sperm from the male gametophyte fertilizes the egg and the other sperm fertilization a central cell in the ovary and forms an endosperm, which is the food supply for the seed, while it is dormant within the fruit. The seed develops into the sporophyte, which is diploid. Then the life cycle begins again. The adaptive nature of the angiosperms provides the beauty of spring and the nutrition fruits.
Tuesday, April 5, 2011
Before I was even finished taking the assessment test I realized that I knew very little about ecology and the behavior of animals in general. Yeah, I got a taste of it in the early Biology classes but I never needed to take the specialized classes of Ecology or Zoology to get where I am now. So, while looking at various sites and blogs on ecology and animal behavior, I came across a really interesting article on the differing brain sizes in migratory birds versus residential birds and I just had to read more.
There are two major questions scientists asked about the brain size of these birds: is the smaller brain a result of migration or does a smaller brain predestine a bird to migrate? Along with their colleagues, Daniel Sol and Núria Garcia who are CREAF researchers studied 600 passerine species with varying habitats. Within these 600 species, Sol and Garcia found that migratory birds do indeed have smaller brains than residential birds who tough out the sometimes harsh seasonal changes. They also concluded that the decreased brain size is a direct result of migration--contrary to the previously accepted 'protective brain theory'.
As earlier studies have shown, having a larger brain is more desirable than having a smaller brain due to it's large cognitive holding capacity. This theory holds true for residential birds who remain in their habitat from birth until death and who need to constantly learn how to stay alive, search for food, and fend off predators. However, with migratory birds, familiarity and knowledge of their surroundings is not as important since their stay in that area is only temporary. The cost-benefit idea is also a valid explanation of the smaller brains in these birds. The amount of energy they would spend learning the only transitory habitat could be put to better use during their travels. Sol and Garcia stated that "for these species, their innate behavior can be more useful than learned behavior".
As a follow up to their research, the researchers added that an analysis of the pallium and telencephalon in the bird brains would be beneficial to their conclusions since these areas are "involved in learning and behavior innovation processes".
Monday, April 4, 2011
Tuesday, March 29, 2011
An intruder enters, and suddenly it is met by a force that begins the fight. After time, backups arrive to fight until the end. This may sound like the plot of an action or war movie, but really I am talking about the body’s immune system. The initial troops are known as the innate immunity and the ones that come in later are the adaptive immunity. The innate immunity can consist of the physical barriers, such as the skin and mucous membranes. It also involves the secretion of chemical signal, fever, and inflammatory response. The innate immunity is supposes to prevent entry and spread of invaders throughout the body.
The more complex system of immunity is the adaptive immunity. We can call the adaptive immunity, the special force for fighting infection. Once the body is exposed, it reacts by activating B and T cells. The T-cells are a part of the cell-mediated immunity and the B cells are a part of humoral immunity. The humoral immune response is mediated by the release of antibodies. Antibodies are also known as immunoglobulins and have a Y shape that consists of two large heavy chains and two smaller light chains. The antibody has a specific binding site for the antigen or intruder. Once the intruder is bound to the antibody, it is destroyed on-site or is marked for later destruction.
The antibody is specific to its target and since new mutations of bacteria and viruses come around every day, how is the body able to adapt to making so many different antibodies when the genome is so small? A person can produce a million different antibodies and the way we can do this is through DNA rearrangement followed by alternative splicing of the RNA transcript. Let us first discover the marvels of DNA rearrangement. DNA rearrangement is gene reorganization. Gene segments containing information about the formation of antibodies come together and are assembled during the formation of B cells. DNA rearrangement brings together and assembles the antibody coding segments. The different arrangements of the segments allow for many forms of a protein from a small group of genes. The diversity of the B cell formation lies in the formation of the heavy and light chains of the antibody by using variable combinations of genes. In the light chain, DNA rearrangement combines three separated genes to code for one polypeptide. In the heavy chain, four genes are shuffled around by DNA rearrangement to produce the polypeptide. Another factor that affects the variability in antibodies is alternative splicing. Once DNA is transcribed into RNA, there are modifications that must be made. One of the changes is cutting out the introns and exons. This can occur by not cutting out an intron that normally would have been removed or by changing the arrangement, in which the exons are joined after the introns are removed. This allows for variation is coding during translation, leading to new forms of a protein. The process of producing antibodies is complex, but it allows our immune system to hone its skills for fighting intruders.
Monday, March 28, 2011
Friday, March 25, 2011
Monday, March 21, 2011
Sunday, February 20, 2011
|Dr. Guevara, Ecuador Institute of Endocrinology.|
Tuesday, February 15, 2011
You know how when you get a new car (maybe not new, but new to you) and all of a sudden it seems like almost everyone on earth has that same car? You see one beside you in the Walmart parking lot, one stopped at the red light…you get the point. Science is exactly the same. Until some scientific topic stares you right in the face, you don’t take all that much notice. This was the same with me and the topic of strokes until this summer when my dad had one. Now every science news website I look at, I can’t help but read the ones with a headline relating to strokes. He first had a TIA (transient ischemic attack) which is also known as a mini-stroke. He was having slight trouble talking and seemed confused but everything was fine. Within a few days he had a stroke which caused one side of his face to droop and he lost his speech. He also couldn’t remember how to do simple tasks such as making the coffee he had always been making because he didn’t even know where to place the water. All of these crazy things made me wonder what the heck was going on inside of his body due to one tiny blood vessel is his brain being blocked.
New research indicates that the TIA my dad initially had isn’t necessarily transient like the name implies. It can actually have long lasting effects and hidden brain damage. The patients studied in this research all had resolved the effects the mini-stroke had on their motor systems within 24 hours and when clinically evaluated 14-30 days later they showed no impairment. Interestingly though, when the patients were subjected to a brain mapping procedure it unveiled that the brain actually had damage that lasted much longer than was once thought. The brain cells on the affected side of the brain showed changes in excitability making it harder for neurons to respond.
Since these TIA’s are often warning signs and the chance of a stroke in the days following a TIA is greatly increased, this mapping technique may be of great help. Doctors say that by refining this technique they may be able to identify which patients are at greatest risk for a stroke following a TIA and therefore direct treatment that is more suiting for each individual case. My dad unfortunately was one of the patients who did end up having a stroke following his TIA, but it has been over half a year since his stroke and he is making great progress. His cognition is almost back to normal and he can speak full sentences now. The recovering that is going on within his brain now is an even more remarkable thing with both hemispheres of his brain working to compensate. Information about this can be seen in the article The changing roles of 2 hemispheres in stroke recovery.
Monday, February 14, 2011
You can never forget your first kiss: the range of emotion surging through the body as your lips meet for the first time. As humans we are compelled to kiss, but what causes humans to want to exchange saliva and bacteria with another person? The answer to this is evolution and chemicals of course. In Sheril Kirshenbaum new book the “The Science of Kissing: What Our Lips Are Telling Us," it explains the origin and continuation of kissing. The scientific word for kissing is osculation and the definition of a kiss is the “mouth to mouth orientation of two individuals or the pressing of one’s lips on some other part of another’s body.” So now that we know what a kiss is, there are many questions that must be asked.
When did kissing begin and Why? Kissing has perplexed scientist for years. Even Darwin pondered the origin of the kiss. The explanation he asserted was kissing was innate or perhaps hereditary. This theory has been combated by anthropologists who would believe the kiss is a learned behavior. This kissing debate seems to stem from the many different reasons people kiss. Therefore looking at the evolution of the kiss is complex. It can be assumed that since the origin of the kiss cannot be pinpointed, the reasons for the behavior cannot be ascertained. This means that kissing was not likely developed from one single behavior. The scientific obscurity continues because kissing has no clear classification system that characterizes the different types of kisses or related behaviors. One theory of why kissing evolved was suggested by V.S. Ramachandran of UC San Diego, it says we are drawn to the color red. This was because our primate ancestors needed to detect ripe fruit. This recognition of red would allow them to survive and produce viable offspring. Therefore this attraction to the color propagates and attracts mates based on the color of the lips. It was found in a study that when male volunteers were shown photos of women wearing various lipstick shades. The men consistently chose red as the most attractive.
So after attractive and the lips meet, what exactly happens in the body? First a chemical cascade occurs, the pupils dilate, the heart rate increases and breathing becomes irregular. Dopamine is release, which excites the reward centers in the brain. A good kiss often leads to the rise in a chemical called oxytocin that leads to strong feelings of attachment. Kissing also allows for us to unconsciously assess the compatibility of our mate. Genes called the major histocompatibility complex (MHC) control the effectiveness of our immune systems. This means that if a diverse MHC is detected when kissing another person the connection may be more memorable. This is because this match would lead to offspring with healthy immune systems. In the end, nature is really choosing if a first date will lead to a second. Understanding the kiss is multifaceted, but it all comes down to the chemistry.
Tuesday, February 1, 2011
We’ve all seen the Grinch and you know what they say, his small heart grew three sizes that day. We all know how impressive we find it that the terrible Grinch used to have a heart two sizes too small and now he has the biggest of all. That is extraordinary until you hear it from me, octopuses have not one heart, not two, but three!!!
Okay now that I’m done with my poor attempt of trying to rhyme and be clever, let me explain to you what caused me to come across this information. The other day when reading Don't be Such a Scientist by Randy Olson, he told a story about an octopus using its beak to maul a diver who was trying to get a picture with the massive creature. It explained that the diver only got away after he finally relaxed because when he struggled with the octopus, its grip only got stronger and its bite harder. I found this interesting so I went searching for more information.
The biggest octopus is the giant Pacific octopus which is a whopping 110 pounds and can be up to 16ft in length. Although these creatures are huge, they are by no means dopey and stupid. Studies have shown that they can distinguish between shapes and patterns and have short- and long-term memory! They also have the ability to lose an arm in order to trick a predator and it will grow back in 6-8 weeks. Now on to its three hearts; one main heart is used to pump blood to the entire body while two are used to pump blood through the gills where waste is dumped and oxygen-rich blood is then pumped back to the main heart. Also, the blood of an octopus contains hemocyanin instead of hemoglobin so the blood is blue!
I tried to use the arouse and fulfill technique by adding the introduction about the Grinch to make people wonder what the heck this science blog was talking about. I am not very good at the "show me, don't tell me" and often find myself blurting out fact after fact, which I did the same here L But I tried to incorporate a video which may help to offset my ramblings. I also tried to use active voice when writing the blog. I need to work on transitioning from paragraph to paragraph and sentence to sentence.
Monday, January 31, 2011
The picture to the left shows API2 and MALT1 binding to NIK. API2 and MALT1 are fused together in certain subsets of lymphoma. The API2 part of this fusion can bind to an enzyme called NIK. When this binding occurs, MALT1 cleaves NIK. This cleaving makes NIK more stable. (credit: University of Michigan Health System)
When NIK is cleaved, the regulatory region is removed. NIK is now an enzyme gone wild. It makes cancer cells that grow very aggressively, spread easily and resist all of the traditional cancer treatments.
The fusion protein is found 30-40 percent of the time in the B-cell type MALT lymphoma which is mucosa-associated lymphoid tissue.
The MALT lymphomas that have this fusion protein have been found to be more resistant to treatment, more aggressive and have larger tumors throughout the body.
NIK cleavage only happens when this fusion protein is bound. Because of this, researchers are looking at NIK as a target for new drug therapies.
click here for the link to this news story and the journal reference.
In the above post I used a hook to get readers interested, used active voice and tried to give the readers a visual via a picture and language of what might be happening during this fusion and subsequent binding.
Sunday, January 30, 2011
Crime shows sell. It’s the thing that has been keeping bread on the table for people like Dick Wolf (producer of Law and Order) and Jerry Bruckheimer (producer of CSI). They make science accessible to the public. They incorporate kernels of truth, hidden within the finesse of Hollywood. The fancy clothes, the perfect makeup and of course the magic database that knows all. Take this quote from CSI Las Vegas:
Gil Grissom: I just got a page from James Watson.
Nick Stokes: And I got one from Francis Crick. What's going on, Greg?
Greg Sanders: Well, as you both know, Watson and Crick are the granddaddies of DNA. Without their discoveries, I'd have nothing to do all day.
Nick Stokes: What have you been doing all day?
Being a scientist this banter is very entertaining. It was all in knowing Watson and Crick discovered the structure of DNA. Does the non-scientist viewer glean this information for this banter that will take less than a minute of screen time? Probably not. While reading a report done by the National Science Teachers Association, this topic of ignoring practical and careful science was discussed. Since shows like CSI and Law and Order can out, there are significant increases in students pursuing degrees in criminal justice, criminology and forensic science. The central question that comes from this fact is “Do we really want all this falsely assigned attention?” In a crime lab on CSI, the scientist receives a sample and within the work shift shown in the show, the unknown sample has been identified as a nylon fiber rug made in the 1970’s. In reality, trace evidence may take weeks to identify. Also the DNA evidence is collected, extraction, amplified and identified within hours, where in reality it could take 5-10 days. The disparity between Hollywood and reality lies in the funding. Currently many crime labs struggle with increasing case loads. In a report put out by the National Research Council, it states the primary funding is focused on advancement in DNA technology. The lack of equal funding leaves many loose ends. Also in the report, it discusses the necessity for assessing the validity of certain assay and standardizing practices used in crime labs nationwide. Another thing was laying down guidelines for education of forensic scientists. One of the biggest concerns in the proper collection of data would be that all scientist use valid methods and proper technique when analyzing data. Personally I know I do not watch CSI for the scientific merit hat it exudes, but for the vanity. Hopefully one thing that can come from the inaccuracy of the science presented is a hope for ethical and better regulation of forensic science in the future.
In this blog post, I tried to hook the reader by choosing a popular television show. I tried to avoid using jargon or delving to deep into science of forensic. In this post I was trying to express the importance of understanding proper and practical science. The article I found was focused on the uses of forensic sciences in education. I think as scientists this idea of accessible science through popular culture can be helpful in showing the ethics and applications of science.
Wednesday, January 26, 2011
The immune system has always been very interesting to me plus the author is a peer. He is a guy named Kevin who is getting his PhD in immunology. I like that he has a witty voice in his blog along with recent research and his own knowledge.
The next blog I picked was one called respectful insolence. Even just the name intrigued me.
This guy sounds to me like an intelligent smart ass. He is a surgeon/scientist that said he posts miscillaneous ramblings. I think I like it although im afraid his ego might get in the way of what he is trying to convey. His posts can be somewhat long but I am interested in what this guy has to say.
Tuesday, January 25, 2011
A blog that kept me reading for more was Sandwalk. It is written by a biochemistry professor at the University of Toronto and the extended title of the blog describes its content perfectly: Strolling with a Skeptical Biochemist. The blog consists of a smattering of topics, some of which I do not necessarily agree with, but nonetheless will read in order to see other views of the topic. This blog serves as an awesome footbridge to a lot of very valuable information. Another blog that caught my eye was The Last Word on Nothing because it again has a large amount of different information that keeps my attention until the end. Although I have noted two blogs that have a general theme to them, I think I would enjoy a more specific blog more. Perhaps one on strictly neuroscience, or chiropractic, or maybe even one's journey through undergrad (with a science degree) through grad school and even their post-grad travels? I guess we'll see...
Sunday, January 23, 2011
So blogging for the first time can be very intimidating, especially after reading all these witty blogs. So while exploring the “Blogosphere,” I discovered Dr. Isis. She writes the blog On Becoming a Domestic and Laboratory Goddess. What first attracted me to this blog was the name. Then when I began reading, I realized she was speaking to all female scientists out there. She always has some hilarious videos she adds to her blog. Her ability to relate pop culture to science is refreshing. She also takes time to call out injustice and puts the spotlight on the trials that come with being a female scientist. Overall the blog was about embracing science and life and figuring out how that two fit together. Another blog that caught my eye was Bioephemera.This blog had an eclectic mix of posts. The blogger, a molecular biologist, seemed to move away from the ordinary scientific topics, and blended science, art, and just random science related facts. One of my personal favorite posts was about an artist who made an anatomically correct dress depicting the major body systems. So I guess the things that attracted my attention were the unconventional, the bloggers who were thinking outside the box. Those who were taking their other interests and mixing in their love of science.