AP Biology class blog for discussing current research in Biology

Author: bg95

Hope for Cocaine Addicts?

Cocaine, known as “the caviar of street drugs”, is expensive and has “powerful, negative effects”. Roughly 25% of americans between the age of 24 and 36 use or have used cocaine. Despite the dangerous effects of cocaine, After marijuana and amphetamines, cocaine is considered to be the most widely available drug on high school and college campuses in the United States. In 2002, there were 212 hospital admissions for cocaine abuse per 100,000 residents aged 12 or older in New York. Because cocaine use is so prevalent, it is important to raise awareness and to help addicts stop using.

Image taken from WikiMedia


What happens when you snort cocaine?

The cocaine quickly enters the bloodstream and travels to the brain. In the brain, cocaine interferes with neurotransmitters. Cocaine blocks norepinephrine, serotonin, dopamine, and other neurotransmitters from being reabsorbed. The resulting chemical buildup between nerves causes euphoria or feeling “high.”



Long term use of cocaine can prevent neurotransmitter to be released naturally in the brain. This means the only way to feel good is to do cocaine again. It is estimated that there are 200,000 people in the united states addicted to cocaine.


Stopping the use of cocaine is a painful and even harmful experience for addicts. However, recent studies have indicated that there may be a fast track to addiction recovery.In addicts, the drug compulsion can be blamed on a group of “sluggish neurons” that rely on drugs to be stimulated. In drug-addicted rats, the drug compulsion was eased by a laser stimulated those affected neurons.

This experiment seems to partially solve the issue of cocaine addiction. Laser therapy could make the withdrawal of cocaine a much more doable process. However, there is still part of the problem to address: relapse. Most previous addicts relapse when they are surrounded by users. this is because the sight of cocaine triggers the memory of the euphoric high they used to experience on cocaine.


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Can we fix the expensive problem of obesity??

Today, America faces what can be considered an “obesity epidemic”. An estimated 69 million americans are considered obese, and obesity is the #2 cause of preventable death in America. Obesity can lead to a number of dangerous conditions and even life threatening conditions. Consequences of obesity include coronary heart disease, type 2 diabetes, different types of cancers, stroke, live disease, sleep apnea, arthritis and more! In addition to health consequences, the epidemic of obesity in america also includes severe economic consequences.  In 2002, the estimated health care expenditure for obesity-related issues was $147 billion

taken from WikiMedia



The statistics concerning obesity, childhood obesity, money lost due to obesity etc. are shocking. America is deeply affected by a preventable issue affecting roughly 35% of adult americans and 20% of youth americans. Scientists and doctors have long explored ways to address this issue medically. Until recently, it was believed that the part of the brain controlling appetite is fully developed before birth, and therefore, cannot be altered. As genetics play a big role in weight and appetite control, the ability to alter the appetite control center (the hypothalamus) would be a huge step in “curing” obesity.

However, “research published in theJournal of Neuroscience has identified a population of stem cells capable of generating new appetite-regulating neurons in the brains of young and adult rodents”. This information suggests that altering the appetite regulation system in humans is a possibility.

There is now hope that “the neural circuitry that controls appetite is not fixed in number and could possibly be manipulated numerically to tackle eating disorders.

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The damages of Sleep Loss

Roughly 30 million Americans are “just trying to catch up on their sleep.” 20% of Americans report that they get less than 6 hours of sleep on average. This nation-wide sleep loss is “taking a toll on our physical and emotional health, and on our nation’s highways.” Sleep loss leads to a variety of inconvenient issues.

image taken from WikimediaCommons

According to Discovery Health, Inability to handle stress, inability to concentrate, poor memory, poor decision making,  increased appetite, diminished motor skills, relationship trouble, medical problems, and mood swings can all be the ill effects of sleep deprivation. This has been known by scientists for a long time, but the reasons on a molecular-level were unclear.

However, recent headway has been made in understanding the consequences of sleep deprivation on a molecular level. A new study at the University of Surrey in England showed changes in gene activity in 26 people who had built up a sleep deficit. Reports in the Proceedings of the National Academy of Sciences showed that after a week of considerable sleep deprivation the blood tests of the 26 subjects showed changes in 711 of their genes.

The “changes” observed in the genes including a disruption of the cell cycle; the cells stopped their circadian rhythm. On the other hand, cells that don’t typically follow a cycle fell into a daily rhythm. Many of the genes that showed changes were related to the immune system. This would account for the previously and widely observed medical issues connected with sleep loss. “The researchers conclude that skimping on sleep can drastically change the body’s daily rhythms and may lead to health problems”.



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Why is it so hard to stop drinking?

It is well known that alcohol is an addictive substance that is hard to quit. The question is why? Some factors of alcoholism are genetic. People whose brains “release more natural opioids in response to alcohol may get more pleasure out of drinking and may be more likely to drink too much and become alcoholics” Also, the orbitofrontal cortex, which is “a brain region linked with decision-making” is affected by alcohol and is a factor of addiction. In addition, Alcohol triggers dopamine release in the brain, a chemical known to spur satisfying feelings. If all of these factors leading to addiction aren’t enough, scientists recently found evidence of a chemical that makes it hard to stop drinking alcohol.

taken from WikimediaCommons

Researchers from the Journal of Clinical Investigation found that long term alcohol abuse leads to higher levels of acetate. Our brains usually run on sugar but recent studies show that heavy drinkers are better able to use acetate to fuel their brain.

Studies show that heavy drinkers were more adept at transporting acetate to their brains than light drinkers. In addition heavier drinkers “burned the chemical about twice as fast as light drinkers”. This showed that the brains of heavy drinkers are able to use alternate energy sources very efficiently. This may seem like an advantage but this extra energy source makes the body even more addicted to alcohol.





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Seals in the Antarctic

Today, thanks to modern technology and social networking, there are few parts of the world that remain inaccessible. You can learn things about places you have never been just from looking on your computer screen. However, there are still small parts of the world unexplored and untouched by humans. Antarctica is one of those places sheltered from humans by impossible weather and environment conditions.  “In fact, About 98% of Antarctica is covered by ice that averages at least 1 mile (1.6 km) in thickness” and the average temperature of the continent is -49 degrees celsius.

Explorers and scientists have attempted to learn what they can about the frozen continent but time spent there is limited. Even more seemingly impossible to reach is the Antarctic Ocean Floor. It is tough to study the “extreme Antarctic environment, where observations are very rare and ships could not go”.  To fix this gap of knowledge, scientists attached sensors to the heads of elephant seals. These seals are adapted to the freezing conditions so they can survive in the Arctic ocean with a temperature average of .5 degree celsius.

Southern Elephant Seal image taken from WikimediaCommons


Thanks to the elephant seals, “scientists better understand how the ocean’s coldest, deepest waters are formed, providing vital clues to understanding its role in the world’s climate”. The seals allowed greater insight to the Antarctic bottom water-

“a layer of water near the ocean floor that has a significant impact on the movement of the world’s oceans”. These areas were previously known of but no real data had been obtained. The seals went to areas of the coast line where “no boat could ever go”.

Studies have shown 50 year long trends in these deep water changes. Scientists hope the new data obtained through the seals will help to further uncover these trends that affect global climate change.

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We All Owe Mice a “thank you”

Recently in our AP Biology class, we read about advances in stem cell research. Important developments began with experiments involving mice. The scientists were able to generate induced pluripotent stem cells from mouse fibroblasts and were later able to generate iPS cells from human fibroblasts . The research as been extremely helpful and scientists were able to learn a lot through the mice cells. It turns out mice are useful for many other avenues of medical research.

Mice have become a critical tool in the quest for new drugs and medical treatments because their genes are remarkably similar to a person’s”. Mice affected with various human ailments, such as “obesity, diabetes, cancer and countless other conditions are being used to study both the illnesses themselves and potential treatments”.

photo from WikimediaCommons









The latest “mouse sacrifice” for society involves cigarette smoke. We know that cigarette smoke heavily damages the lungs but scientists and doctors have long wondered what it does to the brain. There is an established, but “murky”, relationship between cigarette smoking and Alzheimer’s. A recent study with mice inhaling cigarette smoke significantly strengthened the suggested relationship.

Scientists led by Claudio Soto of the University of Texas Medical School at Houston exposed mice to cigarette smoke for four months. These exposed mice all showed signs of Alzheimer’s. Additionally, mice were bred with Alzheimer’s and then later exposed to cigarette smoke. These mice exhibited significantly worsened Alzheimer’s symptoms.

This sort of research proves extremely beneficial to humans and will most likely continue to become even more popular. Already, there are as many as 25 million mice used for medical research each year.

It seems as though we will have many mice to thank in the future.


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Why do only some COCAINE users become addicted?

The obvious precursor to cocaine addiction is cocaine use. However, some people are able to use cocaine on and off with out becoming addicted while others become afflicted by addiction very quickly. There has always been the theory that your personality can make you more prone to addictions and other “weak” decisions but recent studies go a step beyond that and link addiction to the structure of an individual’s brain.

The frontal lobe of the brain is associated with self-control. The size of the frontal lobe appears to indicate how susceptible an individual would be to cocaine addictions. A study done by scientists at the University of Cambridge compared the brains of casual cocaine users versus cocaine addicts. What they found was a noticeable difference in size of the frontal lobe: users had a larger frontal lobe while addicts had a smaller frontal lobe.

The scientists believe that the size difference was preexistent and  not a result of drug use because both groups were cocaine users. The main difference was that the mere users “could take it or leave it” due to their more powerful self control.

The brain is a popular subject when it comes to addictions due to the harm addictions can cause and due to the hope of a better understanding of addictions so that they can be “cured”. There are newly defined addictions more and more frequently, as addictions to food, caffeine, internet, and shopping become more and more prevalent.

Another example of increased susceptibility to addiction is the genetic or hereditary quality of alcoholism. “Though the exact mechanisms haven’t been identified, experts in alcoholism widely agree that some people are genetically vulnerable to developing the disorder.” Also, experts suggest that many people addicted opiates may have “deficiencies in their brain reward systems.”

Further studies exploring the links to the brain and addictions would be instrumental in curing the countless addictions that interfere with people’s quality of life.


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The Woman who cant be Afraid teaches us about Fear

A lot of people say they aren’t scared of anything, but the reality is every body is scared of something. Everybody, except a woman known as SM.

SM had a rare illness that caused damage to the part of her brain associated with fear. The amygdala “is involved in many of our emotions and motivations, particularly those that are related to survival”.  In the same way that pain is a warning sign in attempt to protect you from danger, fear is a function of protection. Without fear you would constantly place yourself in dangerous situations with out responding to an impulse of survival.

The Amygdala- the area of the brain responsible for fear

The damage to SM’s amygdala caused her to lose the ability to feel fear. Scientists tested her on several simulated and real life situations such as being held up at gunpoint, watching scary movies, watching domestic violence. SM felt no fear what so ever in any of these situations. Scientists naturally would predict that with the loss of a functioning amygdala, SM would never feel fear again.

Yet, one day SM had a panic attack. The panic attack was brought on in an experiment where SM inhaled a small amount of carbon dioxide that created a short feeling of suffocation.

The fact that SM felt fear from a panic attack without an amygdala “illuminates some of the brain’s most fundamental processes and may have practical value in the study of panic attacks.” Additionally, it suggests that there may be an alternative center for fear responding to internal threats- such as suffocation or a heart attack.

This study is particularly fascinating because it shows just how little we know about ourselves and the world around us. It illuminates the flaws in our apparent definitive knowledge and encourages further research and speculation about what we know concerning the brain.


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Over the years, as scientists attempt to fathom life on other planets, water has been the focal point of their searchings. Humans can only live about one week with out water, while other animals, such as dogs, can only live about three to four days with out water. Therefore, it is logical for scientists to deduce that for there to be life on other planets, there must also be water.

Recently, a unique “martian meteorite” was found in Northwest Africa. It is the first meteorite found that contains “substantially more water“. Also, it is “in a a class in itself” concerning its chemical make up. Scientists speculate that the “martian crust” came from Mars, as it resembles rocks and soil previously found on Mars. The differences scientists have found between this new meteorite, labeled Northwest Africa 7034, suggests that Mars may be more diverse than expected.

New Martian Meteorite containging record amounts of water.

There is the possiblity that the meteorite was contaminated by water on Earth, though scientist Derek Sears maintains that “it doesn’t look like terrestrial water”.

Either way, Northwest Africa 7034 is an interesting new discovery and has helped to build upon our knowledge of the universe around us. The thought that there are still so many things we have yet to discover is exciting.




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Hubble's Sharpest View of Mars



Can we fight off AIDS?

AIDS is a tragic epidemic world wide. More than 34 million people are affected by AIDS and in 2011 alone, 1.7 million people died from AIDS. The people affected by AIDS are largely from regions in Africa and Asia, but more than one million people in the US are living with AIDS.

Obviously such a prevalent disease attracts scientists looking to help find a cure from all over the world. There have been significant advances in medications that can prevent symptoms and prolong life, but there is yet to be a cure.

A new discovery in treatment for AIDS gives hope for a long term or even permanent control over the HIV. The treatment includes a vaccine with a disabled version of the virus. The heat-inactivated version of HIV “awakens immune protection in some patients”. This means certain patients didn’t have to take their medication for weeks or even months. Thought the affects of the vaccination are temporary, this method of treatment shows promise.

Even if scientists don’t come up with a more permanent treatment for HIV in the near future, the temporary suppressing of the virus results in “knocking the virus down to extremely low levels would mean many patients wouldn’t need drugs, wouldn’t show disease symptoms and wouldn’t be likely to transmit HIV to others.” This is a significant accomplishment. It could lower the amount of people infected with AIDS world wide by stopping the transmission between people and would also improve the quality of life for AIDS infected people.



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Earth taken by Galileo after completing its first Earth Gravity Assist

Old People and Their Memories

Old Lady

For old people who fear severe memory loss or forms of dementia, there is hope!

Scientists have found that there are several simple activities and mental exercises that can prolong a healthy memory. As people get older they retain certain types of memory, such as semantic memory and procedural memory. Semantic Memory includes common sense, general knowledge about the world and basic things such as vocabulary. Procedural memory includes simple everyday tasks.

However, other parts of the memory do not fare as well in old age. Important types of memory such as episodic memory, source memory, working memory and prospective memory do not function at the same levels they once did. Any loss of ability in these types of memory can lead to inconvenient things such as forgetting appointments, being unable to recall past events, inability to retain short-term memory and more!

Help Yourself!:

It is important to understand that memory loss is not inevitable.

For those aging citizens who wish to be proactive in preventing any sort of memory loss, there are proven ways to “bolster memory in old age”. Here are some suggestions scientists have made based on multiple studies:

Making lists or recording information in your phone can help you remember events in the future or tasks you must complete.

Associating information with a certain image, word or phrase can help you to recall names, dates, facts and events.

Another tip rests on the motto “use it or lose it”, meaning the more you use your memory the more effective it will be. This method of improving memory also correlates to the method of staying physically active in order to maintain mental health. Studies have shown that increased aerobic exercise or even just movement in daily life such as walking to work can improve memory. Staying fit physically can also mean staying fit mentally!

This is important for even teenagers to understand. Generally speaking, students don’t have an issue with staying active mentally. Being in class all day long and then studying at home provides more than enough mental activity. The part about staying fit physically, however, is not as commonly accomplished. If you stay fit physically all the studying and classwork you do will be even more productive and you will have an easier time remembering all of the information you are learning.




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The Brain after Combat

The fact that many soldiers suffer from brain damage after combat is no new discovery. One difficult soldiers experience  is  with tasks requiring memory or attention.This is a potentially devastating side effect of serving your country. Because of the weight of this debilitating deficit, scientists continue to research the effect military combat can have on the brain. A study that began by testing the way the brains of “healthy Dutch soldiers” respond to stress in normal life led to important discoveries about the way the brain responds to stress after combat.

This is an American soldier in combat who is subject to the “adverse stress reactions explored in this article.

The areas of the brain that suffer notable damage are the mid-brain and the prefrontal cortex. As before mentioned, these parts of the brain are associated with memory and attention. Soldiers were tested on their memory and attention skills before combat and then again after returning from combat. There were significant differences in the two studies, with alarmingly lower scores in the second round of testing. There is lower activity in the mid-brain and the prefrontal cortex and also a weaker connection between the mid-brain and prefrontal cortex. However, scientists determined that in most cases the brain can heal and return to normal functioning levels after a year and a half.

This was an exciting discovery because it gives hope to any soldiers suffering from the “adverse effects of stress”. This is also an important discovery because it leads to the suggestion of longer periods of time between combat tours. It is uncertain whether or not the brain can heal after “Multiple stressful deployments in quick succession“.

I think it’s important to fully consider giving soldiers more time to recover between tours. This would hopefully prevent long-term damage to vital brain functions.

This issue and discovery are even more relevant to Americans because of the links in brain trauma due to combat and brain trauma due to football. The leaders of the NFL and of the US Army are working together to “improve awareness of traumatic brain injury and further research into its causes, prevention and treatment.” This collaborative effort is focused on prevention of traumatic brain injury by promoting early detection of concussions. If a soldier or player is aware of his or her concussions as they happen they are more likely to take time off to heal before re entering the battle field or playing field.


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