Thursday, December 16, 2010

Cellular Respiration

As our science project this week, we had to create a description of cellular respiration through video, song, etc. We choose to do a video featuring claymation-stop-and-go pictures and acting it out, with the help of our classmates. This is our video, hope you enjoy it!

Sunday, December 5, 2010

Glycolysis and the Krebs Cycle Explained

Here is a SketchFu on the process of glycolysis, the first step in cellular respiration.
The second link is an explanation of the Krebs Cycle, the second step in cellular respiration.

Sunday, November 28, 2010

Phenlylalanine: Key to Healthier Food?

Scientists at Purdue University have found the last undiscovered gene responsible for making of the amino acid phenylalanine. This discovery could lead to controlling this amino acid to raise plants nutritional values and produce better biofuel feedstocks.

Phenylalanine is an amino acid essential in the body of humans, but humans must get it from food they eat (mainly plants). In plants, phenylalanine is important for plant protein synthesis, production of flower scent, anti-oxidants and lignin. Lignin is the principal component in a plant cell wall to help keep the plant stand up and also acts as a barrier in the production of cellulosic ethanol. Cellulosic ethanol is a biofuel produced from wood, grasses and the non-edible parts of plants.

If scientists were able to decrease the amount of phenylalanine in plants, that would lead to a reduction of lignin, which would improve the digestibility of materials originally blocked by the amino acid, creating more biofuel to be easily digested. If scientists could increase phenylalanine in plants, it could potentially boost the nutritional value in some foods. This is because it would increase the amount of anti-oxidents produced in plants (by phenylalanine), which when digested by humans, would have an increased amount of nutritional value.

Finding this gene is important, because now they have all the components needed to replicate this amino acid, hopefully being able to change the amount of phenylalanine in plants, increasing or decreasing depending on the desired function (biofuel or nutrition)


Do Fish Feel Pain?

Do fish feel pain? Pain like humans do? Study done in April of 2009 says they do.

In this study, there were two groups of fish, one injected with morphine, a pain reliever, and the other with a placebo, saline, which is a kind of medicine used to relieve physical pains psychologically (a fake pain killer). After injected, they were treated to a burning sensation, which would not damage any tissue. Both groups of fish wriggled as a response to the burning. However, after time, the fish with morphine went on their day unaffected, while the fish that had gotten saline were weary.

thumbnail (Click image to enlarge)

This shows that fish feel pain because the fish with the painkillers were unaffected and went on the day as if nothing happened, while the fish with the fake painkillers were obviously affected.

From this study, scientists begin to think that fish do feel pain like humans, as previously thought that they do not.

For more information on this study go to:

Sunday, November 7, 2010

Osmoregulation in Sharks

"Osmoregulation is the control of the levels of water and mineral salts in the blood." (Link). Osmoregulation relates to homeostasis, which is where cells have the correct amount of water, mineral salts, glucose and temperature. In every organism, they are trying to create a perfect homeostatic environment, where they can live and thrive as a healthy living thing. Each different organism must do different things to create this homeostatic environment. Sharks are included in these organisms.

Sharks are special because their blood is naturally isotonic to where is lives. This means that the number of solutes inside is equal to the water around the shark. Because of this, sharks are considered osmoconformers, the opposite of osmoregulators. This is usual for marine organisms.

Sharks are able to achieve this isotonic state because of the high concentration of urea and trimethylamine N-oxide (TMAO) in them. Because of this concentration, most sharks are not able to survive in freshwater environments. An exception to this rule, however is the the Bull Shark. In sharks, their kidneys are used to release the salt into the ocean, and determine how much. If a shark were placed in a freshwater environment, their kidney would not be able to adapt to the change in saltiness, causing the shark to die because they can't keep an isotonic state of living. Bull Sharks are different because in a gradual change from ocean to freshwater (example: migrating), their kidneys are able to adapt to these changes, and keep an isotonic state.

Monday, October 25, 2010

Cell Community Comparisons

This week for our blog post, we had to make a Glogster comparing a cell community to any community that we wanted. I chose the New York Yankees, because I believe their team and organization make a great comparison towards eukaryotic cells. Click on the blog below to see this glog.

Wednesday, October 13, 2010

Bad Bacteria: Tuberculosis

Of all the bacteria in existence, almost 99% are good, helpful bacteria. The other 1%, however, is harmful towards the body and can make you very sick, sometimes fatally ill.

One type of harmful bacteria is Tuberculosis, caused by the Mycobacterium tuberculosis bacteria. This disease is transmitted through the air, but is nearly impossible to catch with one social interaction with someone infected. If you are exposed constantly, though, you could catch this disease. 90% of the people who are infected with the disease will stay inactive, meaning they still have the bacteria in them, but they show no signs or symptoms and can't spread the disease. These people, however, can become active and become sick. This means that the remaining 10% have the active bacteria can result in serious sickness, even death.

Tuberculosis is an infection that spreads in your body through the lymph nodes and bloodstream. Although these bacteria can travel anywhere within the body, they are most likely to end up in the lungs. These bacteria kill the tissue in the organs they infect.

Symptoms of TB include: A bad cough that lasts 3 weeks or longer, weight loss, coughing up blood or mucus, weakness or fatigue, fever and chills and night sweats. Although TB can be fatal, there are ways to treat it. To treat TB, usually you take antibiotics ranging from six to nine month to destroy the disease, and the differences in antibiotics depend on your age, overall health, drug resistance, form of TB and the infected location in the body. People who have inactive TB can also take these antibiotics to prevent it from becoming active.

Mycobacterium tuberculosis: Mycobacteria are waxy celled, pleomorphic rods, which range from 2-4 micrometers in length, and .2-.5 um in width. These bacilli cells also have a high concentration of lipids in them, called mycolic acids. Because of this, they have a resistance to many antibiotics. Also, these lipids are hydrophobic and affect the permeability, allowing of liquids or gases to pass through, in the cell wall. These are found in habitats such as water or soil. This specific TB causing bacteria has been causing harm since before human times. Evidence shows that this transferred over to humans through cows in 8000-4000 B.C., through milk consumption. For more information on this bacteria, go to this website


Wednesday, October 6, 2010

Macromolecule Lab

In class, we did a lab testing substances for four different macromolecules (Protein, glucose, starch and lipids). These substances included egg whites, egg yolks, potatoes, apples, onions, strawberries and lemons. My substance was onion, which tested positive for protein and glucose and negative for starch and lipids.

This nutrition fact proves what we found. It says that there are carbohydrates in onions. Also, it says that there is one gram of proteins in onions, which we also tested positive for. This nutrition fact also says that there is zero grams of fat in an onion, which we tested negative in. In this picture, it doesn't say anything about starch, even though onions don't have starch in it. This plant website explaining starch has an excerpt that says "Bulbs like garlic and onion store food in the form of sugar rather than starch."

Through this lab, we were able to find out what substances had what in them. This lab was extremely interesting because we could test things that we eat in our everyday lives.

Wednesday, September 29, 2010


Of the four macromolecule categories, containing carbohydrates, lipids, proteins and nucleic acids, I decided to do a Jing video explaining lipids, fats and oils that can be used in an organism for many reasons.

Tuesday, September 21, 2010

The Properties of Water

Water is one of the most vital elements on the planet. There are many reasons that water is so vital, including properties that make water so special:

1) Universal Solvent: This property proves how vital water is because almost anything can dissolve into it. This is possible because when water is formed, the bond (between hydrogen and oxygen) is called a polar covalent bond. This bond is when electrons need to bond with another to fill their electron shells, but the electrons don't share equally. Because of this, one side of the water bond is slightly negative, and the other is positive, as shown in this picture link. Because this bond is both negative and positive, atoms that both have a negative charge and positive charge are able to dissolve into it, thus making it possible for almost anything to dissolve into water.

2) Polarity: Polarity is when a compound of polar covalent bonds have a slightly negative side and a slightly positive side. This allows water to do many things including being a universal solvent, explained above, adhesion, cohesion, and specific heat all explained below.

3) Adhesion: Adhesion is when a substance "clings" to another substance. Adhesion happens because water, being a polar molecule, attracts both negative and positive objects. Because of this, water will cling to another object. As a result of adhesion there is capillary action. This action is, when in a narrow enough space, water will climb up the sides of the object it's clinging to. This allows plants to suck water in from the ground and reach their top, allowing them to live.

4) Cohesion: Cohesion is the exact opposite of adhesion. In cohesion, instead of sticking to other things, it sticks to itself. It sticks to itself because water is a polar covalent bond, and can form a hydrogen bond, which makes it stick to itself. One example of this is a raindrop. When falling, the drops of water stick together because of cohesion.

5) Surface Tension: Surface tention is the tightness across the surface of water. This is caused by cohesion because the water is sticking to itself, causing the surface of the water to have a tight layer that if an if this object is light enough, it will not break through the surface and be able to stand on top of it. An example is this video, and of the picture below.

6) Specific Heat: Specific heat is the amount of energy needed to raise one gram of something up 1° Celsius. The reason this is special towards water is because it has a high specific heat. This is because hydrogen bonds (Polar Bonds that weakly bond to other polar bonds) when bonded together have a higher Specific heat than regular bonds, as shown in this video.
                                                         Specific Heat Explained

This property of water is essential to organisms because it keeps us from overheating and cooling because it takes so much energy to heat up/cool down water.

7) Density: Density is described as the amount of mass in a given space. With that said, it is usual for liquid substances to be less-dense than their solid state because the solid molecules are more condensed into a place than liquids. Water is so cool because it does the exact opposite. When water is in a solid state, it will actually float on top of liquid water. It does this because in liquid water, the molecules are really close together and when they change forms into solids they spread out and form a lattice formation. As shown in these pictures, the left being a solid formation, and the right being liquid.

8) pH (acidity): A pH scale is to test the acidity in a given substance. The reason that substances have different pH levels is due to ionization. Ionization is the conversion of a non-ionic compound into an ion. An ion atom is an atom with ranging numbers of electrons, and a non-ionic atom is when the number of electrons and protons are equal. When ionization happens, a bonded molecule (H2O) breaks apart, and one element takes another element's electron, causing one element to be negative (OH-) and one to be positive (H+). In water, for example, there are an equal amount of positive and negative atoms, which means that it has a pH of 7, or neutral. This is because if, for some reason, a substance has an unequal balance of negative and positive elements, the acidity will shift to more acidic or more basic.

*** For a video on Cohesion, Adhesion, and Surface Temperature, see here.

Friday, September 10, 2010

Prolog, Expectations, and Goals for the Year

After reading the prolog in our textbook and the class expectations on the website, I can conclude that this year will be nothing like IPS. The only similarity that I can think of is that we will have labs and lab reports. Although we will have these labs, I can already tell that the things we will be testing are going to be completely different from separating Sludge and taking the boiling points. Although this course is clearly going to be different from any Science we've taken, I can say that I'm excited. I think it will be really exciting to learn about your DNA, and testing it for yourself (I saw the 9th graders last year testing it). My goals for this year are to fully understand the material, and be able to use it in other contexts. Using technology to get to this goal can definitely help. One example of this is using this blog to look through everything. I like how this year, all or a lot of our work will be filled out on our own blog, so if we are confused, or need to remember a lab, or a homework response that we posted, we can just scroll down and find it.