In science class on Monday and Tuesday, we did a lab to represent the digestion of proteins in the stomach. I found this two day experiment really interesting. To start off with, we were provided with four test tubes which were used to hold the substances that were to be used throughout the experiment. Some of the main materials used in the lab were water, diluted hydrochloric acid, pepsin, blue litmus paper, and white boiled egg. We were instructed to put three pieces of egg into each of the four test tubes. The egg pieces represented what was going to be broken down. After that, we distributed pepsin, hydrochloric acid, and water into the test tubes according to the directions given. Basically, our goal was to observe any reactions of the boiled egg and the litmus paper. We used clean stirrers to touch each of the four mixtures of the test tubes and then with pressure touched the four different pieces of litmus paper. We noticed that test tubes with hydrochloric acid made a greater impact to the litmus paper. The acid made the blue litmus paper pink. However, the more watery substances didn't influence a color change of the litmus paper. From Day 1 to Day 2, there had been major differences in the solutions of the test tubes. For example, on Day 2 some of the test tube solutions were more mushy, sticky, and "bubbly" than the previous day. "Bubbly" refers to "with bubbles." Also, on Day 2 the egg pieces appeared smaller, because of it shrinking over the 24 hour period. A cool discovery I made was that pepsin and hydrochloric acid together would be best at digesting an item. Not pepsin alone, but with the hydrochloric acid, the two would have a strong ability to digest protein. The purpose of the lab was to connect real life science to what is occurring inside our stomachs. My group concluded that it takes time for the stomach to digest and disintegrate food particles. Similarly, it took time for reactions to take place in the experiment. The reactions were more clear on Day 2.
Tuesday, November 8, 2011
Saturday, October 22, 2011
"Winging It!"
In science on Thursday, the class did an anatomy lab on a chicken wing. Basically, the students observed as the teacher dissected a chicken wing. It was really interesting. The students could clearly see the connections between the structure of a chicken wing and a human body. For example, the human body and the chicken wing both have bones, muscle, skin, nerves, tendons, cartilage, ligaments, and fat in common. The idea of the lab was to evaluate how a raw chicken wing can maintain four significant tissues. To start off with, a tissue is a group of similar cells that perform the same function. The different types of tissues were the following:
- epithelial tissue
- muscle tissue
- muscle tissue
- connective tissue
- nerve tissue
Epithelial tissue forms protective surfaces such as skin. In the lab, the epithelial tissue was represented by the outer skin of the chicken wing. Muscle tissue has the ability to contract which causes movement of the structures inside the body. This tissue was represented by the lean meat of the chicken wing or in other words, the white colored material inside the wing. Connective tissue is capable of providing support of your body and connecting all its parts. In the lab, this appeared as the correlation between the bones, the ligaments, the cartilage, and the joints. The joints are the pieces that connect bones together. The ligaments are shiny white covers for joints. Finally, the cartilage is a slippery substance which allows the bones to move smoothly. Nerve tissue has the job of carrying messages between the brain and the rest of the body. Nerve tissue in the chicken wing was vague in appearance but it was shown as a faint strip of red. Another important part of the lab was the fat inside the chicken wing. It was shown as a yellow material connected to the muscle tissue.
All in all, the lab was very fun and interesting. The students concluded that the tissue which actually moved the chicken wing was the connective tissue because it consisted of the bones which were connected by the joints. The bones/connective tissue was surrounded by the rest of the chicken wing. Everyone realized how the chicken wing structure and the human body structure can be similar.
Tuesday, October 11, 2011
The Lab of Diffusion - Class Response
Today in class, we did a lab to learn about the process of diffusion. For the experiment, the baggie of corn starch represented a semi permeable membrane and the iodine substance represented an indicator. My table group observed for about fifteen minutes that the iodine's purpose was to change the color of the corn starch during its direct contact with it. The iodine was significant to the lab because without it, there would be no change in any substance and the corn starch wouldn't have reacted to the diffusion which was taking place. Diffusion occurred because molecules from the diluted iodine water had no space to move around and they were able to identify the less concentrated source of corn starch in the course of the lab. This form of diffusion was osmosis because the water molecules were travelling throughout the permeable membrane which was the baggie of corn starch. The goal of the lab was for the corn starch to successfully turn purple but due to the baggie being too well-made, the corn starch instead turned into a light yellow color. Even though the lab wasn't successful, I thought it was cool how the chemicals were reacting to each other. I was able to understand how the iodine's contact with the corn starch impacted the spread of molecules. Although, it would be interesting to see how corn starch could turn from clear/white to purple.
Sunday, May 15, 2011
Current Event - May
Libya's rebels say dying for freedom is worth it
Who: Ayman Berghthy says he is willing to die for the country of Libya. He has changed his main goal from
being a successful businnessman to being a freedom fighter for Libya.
What: Rebels against ruler Qaddafi claim full power over the city of Misrata. Since Quddafi is trying to shut the country down, Ayman and other fighters are fighting for the freedom of Libya.
When: This story took place on Sunday, May 15. Libyans have been trying to defend the country of Libya "since the first drop of blood" caused by Qaddafi.
Where: The major victory of the Libyan rebels takes place in Misrata, Libya. So far, the rebels declare that they have no plans to advance on Tripoli, Libya, which is the capital of the country.
Why: Rebels are making the decision to die for the freedom of Libya because they are sick and tired of the terror that Qaddafi has given to the country. The fighters have an intent to put the fight to an end and get back to the lives that the fight has put on hold.
How: The people of Libya are boosting the morale of the freedom fighters and giving hope to their beloved country.
I can connect this article to "Los Ninos Heros" of the Mexican/US War. The spanish phrase means "heroic children." In this historic war, six Mexican cadets died for the freedom of the country of Mexico.
Current Event-May 17
Current Event - May 17th.
News link: http://www.cbsnews.com/stories/2011/05/07/national/main20060801.shtml
Who's involved? Mississippi is suffering major floods that can change the environment and the inhabitants. These colossal floods will impact people of the society because some believe that their city will be underwater in the future. This is life changing because many won't have a shelter to live in. Now, residents and officials are preparing for the worst.
What is occurring? Floods are roaring through the state of Mississippi. These flood disasters are capable of breaking world records of historic flood levels. Basically, the Mississippi basin is overflowing. This is mainly being caused by the overflow of the valuable Mississippi River.
When did this occur? This article informs readers of what is to come on the day of May 7. Also, floods in Mississippi are still continuing today and are still devastating lives.
Where did this occur? This article is based in the whole of Mississippi. Also, it talks about people trying to aid the situation in Memphis, Tenessee.
Why are the floods occuring? The floods are occuring because powerful rain is forcing the Mississippi River's basin over its limits. Therefore, the water is being forced into tight areas(tributaries) and throughout the state.
How are people trying to help the situation? People around Memphis, Tenessee are constructing a buffer, filling sandbags, and raising to a higher ground. They are aiding the problematic floods to the best of their abilities.
Mississippi flood may be "large-scale disaster"
News link: http://www.cbsnews.com/stories/2011/05/07/national/main20060801.shtml
Who's involved? Mississippi is suffering major floods that can change the environment and the inhabitants. These colossal floods will impact people of the society because some believe that their city will be underwater in the future. This is life changing because many won't have a shelter to live in. Now, residents and officials are preparing for the worst.
What is occurring? Floods are roaring through the state of Mississippi. These flood disasters are capable of breaking world records of historic flood levels. Basically, the Mississippi basin is overflowing. This is mainly being caused by the overflow of the valuable Mississippi River.
When did this occur? This article informs readers of what is to come on the day of May 7. Also, floods in Mississippi are still continuing today and are still devastating lives.
Where did this occur? This article is based in the whole of Mississippi. Also, it talks about people trying to aid the situation in Memphis, Tenessee.
Why are the floods occuring? The floods are occuring because powerful rain is forcing the Mississippi River's basin over its limits. Therefore, the water is being forced into tight areas(tributaries) and throughout the state.
How are people trying to help the situation? People around Memphis, Tenessee are constructing a buffer, filling sandbags, and raising to a higher ground. They are aiding the problematic floods to the best of their abilities.
Monday, May 9, 2011
Tuesday, April 12, 2011
"Soaring Straws" Lab
Imagine you were an arrow. If you tried to soar through the air on your own, you would no be successful. This is because gravity is pushing you down. Now, imagine an Native American hunter holding a bow, with you pulled back against the "bendy" string. Let's say the Native American hunter has two chances to shoot an animal. When the hunter seeks the perfect opportunity, he launches the "bendy" string back a short stretch and releases. Now, you are flying, but you did not quite reach the target. In his second chance, he pulls the "bendy" string at a long stretch, and releases. BULL'S EYE!!!!! This time the arrow flew a farther distance and was aimed at the right target. How did the Native American hunter's first trial differ from the second trial? The answer is the Elastic Potential Energy was stronger in the second trial than in the first, which impacted a farther fly of the arrow. Elastic Potential Energy is the amount of stretch of an object. In comparison, the Elastic Potential Energy of our "Soaring Straws" lab is the amount of stretch of the rubber band. In this case, the rubber band played the role of the manipulated variable, because its stretch was manipulated and changed. On the other hand, the gravitational potential energy is the height of which gravity is forcing an object to fall. Similarly, the lab suggests that the gravitational potential energy is the maximum height of the rocket in air. This is the responding variable because it is the reaction to the elastic measurement. We experienced a rocket launch, a take-off, and the power of gravity, The potential energy of the rocket turned to kinetic energy just as it was release from the "toilet roll" launcher. I've analyzed an intruiging relationship between the Elastic Potential Energy and Gravitational Potential Energy. I have observed that the more the stretch of the rubber band(EPE), the more the gravitational potential energy of the rocket. For example, when I was in the process of launching the rocket, I stretched the rubber band
1 cm back and the experiment resulted with an average GPE of 8.6 milijoules. In contrast, in the second trial, I stretched the rubber band 2 cm and the result was an average GPE of 19 milijoules.After these trials, I clearly was able to see a major difference and I realized the concept that the more the EPE, the more the GPE.
Even though our lab was very chronological, towards the end, our hypothesis was mistaken. Knowing that the rocket went to an average of .55 meters high with a 1 cm stretch in the 1st trial, and an average of 1.21 meters high at a 2 cm stretch, we believed that the 3 cm stretch of the rocket would prove more in the third trial. However, we predicted wrong, and a unique error occurred. Unexpectedly, the average of the height of the rocket of the third trial was 1.12 meters high. This surprised us because the average third trial height was less than the average second trial height. This impacted the gravitational potential energy of the third trial. In contrast to the first two trials, the GPE of the third trial was 17.6 millijoules. This data is proven in the graph. Some possible reasons why the third trial did not turn out as expected are maybe the thick rubber band was having a weak reaction to the 3 cm stretch that we pulled on it. Another possible reason is that my partner or I did not hold the rocket properly. Subsequently, maybe the rocket, after being released hit the inside of the "toilet roll" launcher. Next time, we can enhance the lab in various ways. For starters, we can use a different "less-stretchy" object to be used as the manipulated variable. Also,some input I can give is that the project will work more efficiently outside. This is because many times rockets were flying across the room, hitting other students, hitting the ceiling, and getting stuck on top of the ceiling lights. All these distractions can lead to inaccurate measurements. All in all, this lab was fascinating and educational.
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