Digestion Lab

This lab was completed to observe how substances in your stomach work together to digest food. Each of the four test tubes represented a stomach. In test tube A was pepsin, which is a control. This means that it is a significant component in the digestion process. In test tube C was hydrochloric acid, which is also a control. In test tube B was a mixture of pepsin and water, while test tube D contained a mixture of hydrochloric acid and pepsin. Also, in each test tube were three cubes of egg whites, being the food that would be digested. The "digestion system" that was most successful was the one in test tube D. This is because the two controls together make for a faster digestion. Controls, by themselves, can not function correctly; they need support from eachother or another substance, such as water. This lab allowed us to see a model of the digestion system in action and how it really works.

Chicken Wing Dissection - Class Response

Today, the class observed as Mrs. Rousseau dissected a chicken wing to show us the makeup of tissues. We observed the tissues and what other tissues they attach to. The skin is an epithelial tissue, and it attaches to muscle tissue. Fat also attaches to muscle tissue. When we were observing the muscles in the wing, Mrs. Rousseau located the two that bend and straighten the elbow joint. The flexor bends the joint, then the extensor pulls in the bone in the other direction to straighten it. We observed this movement and made a connection to a human arm flexing. We were able to see muscles, tendons, joints, and ligaments working together. When it came down to the bone, we observed the cartilage, which is connected to the bone. This was cut open, and we observed the bone marrow, which was a red color. We discovered and observed many parts, though we did not see any nerves. This observation of this dissection was helpful in making connections to a human body and better understand makeups of the human body.

October 11, 2011 - Diffusion Experiment

In science class yesterday, we completed a diffusion experiment. To begin, a beaker was filled halfway with water. Then, a teaspoon of corn starch was placed into a plastic bag, which was secured shut and submerged in the water in the beaker. The last step of the preparation was to drop iodine into the water. After sitting for about fifteen minutes, the iodine should have diffused into the plastic bag, which is permeable to liquid substances. The mixture of iodine and water should have entered the plastic bag, changing the starch from a translucent white color to a dark purple color. However, only a small portion of the bag's contents were changed to the purple color, and it was a lighter shade than expected. This may have been because the iodine was not given enough time to complete the full process of osmosis. When this experiment was put in place for an extended period of time by Mrs. Rousseau, the process worked out, and the iodine diffused into the starch. Overall, this experiment was a great way to learn about osmosis and diffusion.

Making a Recycled Gravity Car

When I began to create my car, I tested out a few different ideas of what materials to use and how I would get each part to work together. I tested out bases of water bottles and boxes. When I came upon a decision, I used a recycled box for the base. To begin, I decorated the box with comic newspaper print. Then, I created holes in the side where the axles could go through. After having to make a decision between straws and skewers, I decided to use straws for the axles. Next, I put two CD discss together for each of the wheels. These are fastened in place with putty. After all four wheels were put in place, I placed extra putty for more support of the wheels. Then, I tested the vehicle to make sure everything was successful and working correctly. For more support, I steadied the box and put more support on the wheels so that they would be able to move the vehicle. This vehicle does not have an engine and cannot be accelerated by rubber bands. As a result of this process, my Recycled Gravity Car was created.

Seal Whiskers

    

 It has been known that harbor seals can use their whiskers to detect movement, and that this skill helps them capture their prey. However, German researchers have conducted lab tests that have proven it possible for a seal to distinguish items by shape and size, using only their whiskers.

     During the lab test, a harbor seal's head was placed into a box that is used for experiments, which was placed inside a tank. The seal's essential senses, such as sight and hearing, were made unable to use, so the whiskers' skills could be more easily observed. Paddles were used in this experimentation. As each paddle of different shape and size was placed into the tank, the seal was able to use its whiskers to distinguish it by the disruptions that the paddles made in the water.
     This experiment gave researchers and scientists an idea of how a seal can use body parts other than eyes, ears, nose, etc. to their own benefit. This discovery is impactful in many ways, including the possibility of experiments on other animals to find how they use their uncommon body parts to their advantage. This was a discovery that makes people look at seals in a whole new way. Before I read this article, I didn't even know that seals use their whiskers in a beneficial way at all!


For more information, visit the following link:
http://www.nytimes.com/2011/05/17/science/17obseals.html?ref=research

Soaring Straws: Lab Report

       Gravitational potential energy and elastic potential engery are related and easily observed in this experiment. When the stretch of the rubber band was shorter, there was a greater result of gravitational potential energy. However, there should have been more height and gravitational potential energy with a longer stretch of the rubber band. If the rocket starts lower in the launcher, there is more of an opportunity to fly higher, thus producing more elastic potential energy. When there is more elastic potential energy, it will lead to a larger quantity of gravitational potential energy.
       While collecting this data and creating the documentation, there were many places for possible errors. When we were flying the rocket, we came across one conflict in the data collection. As mentioned before, when there was a shorter stretch of the rubber band (three centimeters), there was more gravitational potential energy and height. This did not go with the relationship between elastic potential energy and gravitational potential energy. I am unsure of how this occurred, but it did not go with the facts of the relationship. Lastly, there are possible ways that this lab could be enhanced. Possible changes include a change of the manipulated variable and responding variable. There could be another element included that would take the role of the manipulated variable. Other than that, this lab was a helpful way to visualize calculations of gravitational potential energy. 

"Branches of Happiness" - Extra Credit Assignment

Branches of Happiness

I face the world alone,

Besides the birds on my branches.

I cannot go far, though the wind will rock me,

And the sun hurts my eyes.

Though my existence seems hard,

You must know,

Being a tree is not so bad.

I get to watch people walking below,

Almost as happy as I am.

Though I am confined to my space in the ground,

I can still have dreams,

And watch humans live them for me.

This poem was inspired by "Dragon Tree" by Douglas Florian. Florian's poem inspired me to write a poem that included personification, and about a tree. However, the idea to write a free-verse poem was my own.