Rocky Shore Investigation

            Shortly after investigating the mangrove ecosystem, the bus took us to the rocky shore, where we were able to explore the beach. The rocky shore was surrounded by jagged rocks, with intense sunlight. We measured the wave frequency per minute using a timer, and the wind was blowing on the direction of north east. The temperature of the ecosystem was measured using a thermometer, and the result was 31 degrees Celsius. In addition to the abiotic factor, the biotic factor was also measured by determining the slope of the rocky shore, as the ecosystem of the rocky shore isn’t flat. Quadrats were then laid and the abundance of the organism was counted.

            We worked at a side where the waves crashed against the rock. The ocean near the shore had nothing much to offer. On the other hand, the organisms teemed the rocks that the waves crashed against. Barnacles, in all sizes and shapes were especially numerous and populated the rocks. Even when the waves crashed against the rocks, the barnacles held on, and was actually great in numbers near the waves compared to rocks that wasn’t anywhere near the ocean. In this ecosystem, human interaction has impacted it. There was a pathway towards the rocky shore, and several boats floating near the rocky shore. These may have affected the distribution of organisms in this ecosystem.

Figure 1: Kite Diagram of the Biotic Factors in Rocky Shore

            Figure 1 shows the kite diagram made using the abundance of the organisms in this ecosystem. 5 quadrat was laid after the slope of the rocky shore has been measured. Barnacles were heavily populating the rocks near the ocean waves, which is signified by the large kite on quadrat 1 and 2 for barnacles on the kite diagram. Periwinkles on the other hand, were greater in numbers on quadrat 4, where it was pretty high up compared to the quadrat where barnacles were numerous. There were a few to none limpets around, as the area was heavily populated by the barnacles. Barnacles are able to clamp themselves onto the rocks, even strong enough to resist the force of the waves crashing the rocks. These adaptation allowed them to flourish where other organisms can’t.  

On a semi-unrelated-note:

Biology HL students gathering for a photo :)

Mangrove Investigation

We went to two sites of mangroves and took measurements of the biotic and abiotic factor. The type of mangrove that we investigated was the red mangrove. By using a continuous belt transects, the population of each species sighted was accounted for. The abiotic factor of each site was also measured. Abiotic factors that were measured included the temperature, DO, pH, TDS, substrate, water quality, turbidity, depth of water, and light intensity. To further strengthen the accuracy of our data, we were divided into teams, and each team had their own data. I was in the Pink Dolphin’s team, and was therefore responsible for the data, and the data shown below will be of Pink Dolphin’s property.

Table 1: Abiotic Factor for Mangrove Site A

 Table 2: Abiotic Factor for Mangrove Site B

The mangrove ecosystem according to the abiotic factors collected, is a humid ecosystem with a pH of around 7. Total dissolved solid’s number was high, and so was the turbidity of the water, making the water’s appearance to become murky. There was a great deal of sediment inside the water, and as a result, the light intensity through the water wasn’t very high as the sediments blocked the sunlight. I learned that there were more than one type of mangroves. There were red mangroves, and mangroves that were colored in bright yellow, and ones that was smaller in size compared to the other mangroves. All of these different kind of mangrove ecosystem had their very own biotic and abiotic factors making them unique individually.

Figure 1: Biotic Factor for Mangrove Site A 

Table 3: Species’ names for Mangrove Site A

 As an example, a bar graph of the biotic factors for Mangrove Site A has been created. Mangrove Site A is the ecosystem belonging to the Red Mangroves. Even though the ecosystem belongs to the Red Mangroves, their population are equal or smaller than other organisms because of their size. One red mangroves has roots called prop roots, which covers a lot of space due to its size. In contrast, the number of lichen (both yellow, and green) is numerous in their population. Lichens are indicators, indicating that the area has a decent air quality, as they only flourish in such environment. Other organisms were also sighted, however due to the limitation of our mobility due to the preservation of mangroves, we were unable to dig further down to investigate and account for smaller organisms hiding out underground.

 Here is a picture of fellow pink dolphins investigating the mangroves.

May Random Mutation Ever be in your Favor

            Natural selection is one of many concepts for Evolution. Evolution is change over time. In order for natural selection to happen, over population, variation, and competition has to occur. After all these conditions have been met, Charles Darwin suggests that the fittest will survive. Fittest doesn’t necessary mean the strongest. Organism with variation that will benefit them in survival over the others will triumph, and will survive and reproduce.

            The snails in the article are an excellent example of natural selection. Cepaea nemoralis is the snails that are being studied for evolution. These snails are highly variable as their shells can be yellow, pink or brown. Their shells can also be banded, which are genetically inherited. This variability is spread out over many regions as their color allows them to survive in different environment. Snails are able to possess different colors of shell because shell color is controlled by a single gene with three alternative alleles. On the other hand, the band in the snail’s shell is controlled by a single gene with two alleles. Researches have shown that darker shells, which are brown or pink, will be able to absorb more solar radiation than yellow shells. Therefore they can adapt to cooler climates, as they can keep themselves warm. Snails that inherited the yellow shell will prefer the warmer climate as they can bathe in sunshine without dying of heat. Their environment also plays a role. If the snails lived in a open grassland, where grasses are yellow, the snails with yellow shells will be able to camouflage among the grasses while the snails with darker shells get eaten by predators. The environment and the climate supports the snails that are best adapted to it, while killing off the rest. The ones that survive grow up and eventually pass on their advantageous gene by reproducing. This is natural selection.     

            Another case of natural selection, which is rapidly becoming a problem today, is the evolution of antibiotic resistance in bacteria. Due to random mutation, a few bacteria will become resistant to the antibiotic. Once a few bacteria are able to resist the antibiotic, it can pass on its gene to other bacteria by plasmid exchange. Antibiotic was first introduced by the usage of penicillin, which was first discovered by Alexander Fleming in 1928. Since then, bacteria have mutated due to over-prescription of antibiotics by the physician, or patient’s incompetence to follow the antibiotic prescription instructions. Antibiotics kill off bacteria which isn’t able to resist it, giving the bacteria’s environment pressure. As a result, only the bacteria with the antibiotic resistant gene are able to survive. With their competition eliminated, they can divide freely, and their population will rise. They can then reproduce and pass on their traits to their offspring. This natural selection of the bacteria eventually produces bacteria that have several antibiotic resistant genes called superbug. This is becoming a major problem as places that are sanitary like hospitals are slowly generating superbug.

http://www.sciencedaily.com/articles/a/antibiotic_resistance.htm

http://www.answersingenesis.org/articles/am/v2/n3/antibiotic-resistance-of-bacteria

            There is a relationship between evolution, ecology and genetics. Ecology is the interaction between biotic factors, and their interaction between abiotic factors. When living organisms interact with each other, competition occurs due to the population of the organism exceeding the carrying capacity of the ecosystem. The ecology therefore creates an environmental pressure for the organism to adapt, and evolve. Organisms that gain an advantage due to random mutation of the genes will be more likely to pass on their genes to their offspring. In the end, the organism that has this genetic advantage will accumulate over time due to natural selection, and evolve to adapt to its ecosystem. 

Hematopoietic Stem Cells and Genetics

We are always in a constant search. You may be on a search for your dreams, money, or even your loved ones. Well not for the chaps at the Erasmus Medical Center! Their researchers in the Department of Biology concerning stem cells have found some rather interesting information. Their findings are still in their infancy age and may not provide immediate breakthrough, however for future research, it is invaluable. Soon, their results may save many lives when pharmaceutical companies decide to create a medicine from their findings.

            Stem cells are cells that differentiate into specific cells that have their own role in maintaining the organism. The peeps at the Department of Biology have been using mice as test subjects. By using Vivo imaging, they were able to find hematopoietic cells in the dorsal aorta at the start of the mice embryonic stage. That was a mouthful to say. Let’s break that down shall we? Vivo imaging is the process used in order to monitor the functions of the cell and its molecular process. Hematopoietic cells are multipotent stem cells. As in, they are undifferentiated stem cells that are able to self-renew them self and differentiate into specialized cells with specific functions. Let’s look at multipotent’s etymology. Multi as in the stem cell can differentiate into different cells and potent as in its potential to differentiate into different specialized cells. Therefore, Hematopoietic cells are undifferentiated cells that can differentiate to all blood cell types. The Hematopoietic cells are responsible for blood production in the adult mouse. Next, the dorsal aorta is the vein from the yolk sac during the embryonic stage. So by using a process to view the molecular activity of mice during its embryonic stage, the researchers were able to find undifferentiated stem cells in the veins of the mice that is capable of differentiating into a specialized blood cell.

            The researchers cut embryonic slices and put them under the microscope to catch the hematopoietic cells in action. There are 2 protocols in doing the experiment. In protocol A, they flush the lumen first, and then proceed for an antibody injection. Then they slice the embryo and put it on a glass slide. The researchers then set the temperature at thirty seven degree Celsius and five percent Carbon dioxide and air atmosphere. Protocol B is very similar to protocol A in terms of procedure. It also flushes the lumen, except it doesn’t inject antibody. Then it also slices the embryo, however now it applies the antibody stain on the embryo. The same temperature and air atmosphere is kept for controlled variables.

Protocol A+B (top) Hematopoietic Cell's Location in mice (bottom)

            Additionally, Researchers from the Children’s Hospital, Boston, Massachusetts, USA found a way to use the hematopoietic cells to cure the mice off its lethal radiation. This is just the beginning. Once the technology has advanced, and the research in this particular field has evolved, the same process can be done with humans, and will cure and save many fortunate patients. The day hematopoietic cells technology is moved into the human system, is the day where breakthroughs will be popping like firecrackers. 

            To help fasten up the research, modified mice can be created to create a setting for experiments. The researchers can use a haploid embryonic stem cell instead of a sperm to fertilize the immature egg cells. This haploid embryonic stem cell only contains the genetic material from the male mouse. Not only does this procedure enable easier reproduction of modified mice, we can also genetically alter the haploid embryonic stem cell in order to satisfy our need for our scientific research. The current procedures to produce genetically modified mice are made from embryonic stem cells which contains two copies of every gene from each of the mouse’s parent. It is a slow and uncertain process as the offspring may not retain traits and genes from their parents that the researchers require.  

            In conclusion, the additional hematopoietic cell discovered in mice has a lot of potential. It proved to us that it can ward off lethal radiation. By genetically altering the haploid embryonic stem cell, we can obtain a more precise modified version of the mouse to experiment on. In the future, the hematopoietic cells may be able to move to the human system after extensive research with genetics on hematopoietic cells until it is presumed safe enough to apply on humans. The age of research in this area is still very young and developing.

Work Cited

Catherine Robin, et al. "In Vivo Imaging Of Haematopoietic Cells Emerging From The Mouse Aortic Endothelium." Nature 464.7285 (2010): 116. Science Reference Center. Web. 29 Apr. 2012.

  

Lyons, Elisabeth. "From Embryonic Stem Cells, a Sperm Replacement and Easier Path to Genetic Modification." EurekAlert! Cell Press, 26 Apr. 2012. Web. 29 Apr. 2012. <http://www.eurekalert.org/pub_releases/2012-04/cp-fes042312.php>.

SL, McKinney-Freeman, Naveiras O, and Daley GQ. "Hematopoietic Stem Cells." Isolation of Hematopoietic Stem Cells from Mouse Embryonic Stem Cells. (2008). PubMed. Web. 29 Apr. 2012. <http://www.ncbi.nlm.nih.gov/pubmed/18770632>.

Genetic Suppression Attack

            We live in a country where mosquitoes can compromise our health with diseases such as malaria. Scientists have been working to find a way to contain the population of the mosquitoes to prevent further casualties from the diseases that they transmit. When we encounter mosquitoes, what do we do? Slapping it, chasing it or spraying it with insecticide isn’t just enough. It’s still going to fly around us and constantly be a nuisance. The mosquitoes will inject its saliva once it finds an opportunity to bite you. This is the reason we itch every time a mosquito bites us. It is also a reason we want to end its life for abusing our skin and blood. However, researchers have found a way to genetically engineer mosquitoes to kill their own offspring. Well, that took them long enough.

            The mosquitoes are engineered to kill their own children by passing on a lethal radiated gene. These children will die before they even reach adulthood. This method is more environmentally friendly than insecticides; however, the side effects of these genetically modified mosquitoes are yet to be known. Since they were modified with a radioactive gene, these mosquitoes will not be as strong as the wild one. Their chance to find a mate will be significantly lower than the natural mosquitoes, making it pointless if they just died without mating. Some researchers have been releasing these modified mosquitoes without permission or in countries with low to no regulations regarding the matter. This causes even the supporters of the research to be worried. These mosquitoes have been released on Grand Cayman Island before and it has effectively reduced the population of the mosquitoes by 80% for three months. So, what’s your opinion about our little genetically modified weapon?

Bibliography

http://www.nytimes.com/2011/10/31/science/concerns-raised-about-genetically-engineered-mosquitoes.html?_r=3&pagewanted=1&ref=biotechnology

 Genetically Modified Mosquito (Left) and it's Egg (Right)

Cloning – The Ongoing Debate

           The next time you are strolling through your local market, be on a lookout for the products that you are purchasing. If you look carefully, you may be able to tell that some products may have distinct markings compared to its similar counterparts. One of them may be a product from a cloned subject. Question. Would you eat a product from a cloned animal? Say, would meat from a cloned cow fill your appetite?

            If you don’t mind it, then good news! The article from the “Institute of Science in Society” contends that the milk and meat from a cloned animal’s offspring would soon be on sale without labels. This means that you may end up eating or drinking a cloned cow’s milk or meat without knowing. Bright future indeed, however some people may find cloning unethical. The first sheep to be cloned on July 5, 1997 called Dolly had people getting off their chair. If Dolly was placed next to her natural sheep, then we wouldn’t be able to tell a difference. Could cloning perhaps be employed into the human society? Most people would argue that cloning humans would be too hard, as even Dolly was a result of 277 previously failed attempts. Clones would also not be totally “identical” to its natural counterpart. As we duplicate cells, it accumulates mutations overtime, causing the gene to differ slightly from its original cell. The cloned offspring may then be infected with disease that may not be known as of yet.

            Dolly was created by the somatic cell nuclear transfer (SCNT). Several attempts have been made using the method to create a cloned human. An American couple tried to pay $500,000 to a company called Clonaid for a clone of their daughter who has already been deceased. As stated before, cloning doesn’t ensure an identical clone. In the end, Clonaid didn’t succeed, however, even if they did, the clone may be ridden with diseases. Would the parents even want a cloned daughter that would remind them of their original deceased daughter? Anyways, do you still want to eat a cloned product?

Bibliography

http://science.howstuffworks.com/environmental/life/genetic/human-cloning.htm

http://www.i-sis.org.uk/Cloned_Meat_and_Milk_Coming.php