Cells R Us

In class on Tuesday, we constructed a life size model of a cell. Everyone in class created an organelle to make up part of the cell. I created the Golgi apparatus. The Golgi apparatus is where proteins are processed, sorted and delivered. It contains enzymes that make changes to the proteins. Some proteins are stored within the apparatus while others are sent to other organelles or outside of the cell entirely. The approximate real size of the Golgi apparatus is 10 um (micrometer). The magnified size of my model was 40 cm. I'm not sure what type of cell it was, considering that there were some organelles present that  were only found in animals, some only found in plants and some found in both. If I had to make a final guess, however, I'd guess that we built a plant cell, considering that one of the organelle's made was chloroplast. Since chloroplast only helps with photosynthesis, I'll guess that it was a plant cell. The largest organelles were the nucleus and Golgi apparatus, the smallest were the ribosomes and mitochondria. If I looked at a cell under a microscope, I'm certain that I'd be able to see the nucleus and possibly the Golgi apparatus. In order to see the really miniscule organelles, I'd have to use an electron microscope. I was surprised by exactly how small the ribosomes were, and the fact that the average amount of ribosomes in a cell is 15,000. I guess that, considering how small a cell is, I didn't think there would be something so tiny inside of it.

How pH affects Enzyme Activity Lab

We recently finished a lab observing Changes in Enzyme Activity. My group tested the effects of pH levels on enzyme activity. To do so, we cut three 1g slices of potatoes and put them in a test tube filled with 15mm of hydrogen peroxide. Then we poured in acid into one test tube, a base into another and water into yet another test tube. We then watched and measured the enzyme activity which could be observed by bubbles being produced on the potato. 

In the Changes in Enzyme Activity Lab, my lab group tested to see if pH affected enzyme activity. pH is the level of acidity in an object or its environment. We hypothesized that the pH would affect enzyme activity. I believed that a higher pH would increase enzyme activity. However, in our experiment, the test tube containing hydrochloric acid produced no bubbles at all. 

Some errors that our experiment had were that the amounts of water weren’t exactly the same and that the hydrogen peroxide levels weren’t the same on each potato. We sort of did a visual estimate when pouring the acid, base and water into each test tube. In the future, we could measure out each liquid before pouring it in. We could also use pieces of the same potato and make sure they all had the same amount of skin. Besides those somewhat conscious errors, I think everything else was under control.

Our investigation on enzymes could be applied to real life in a situation like acid reflux. Perhaps eating foods with a lower acidity could keep the condition in check. WE can manipulate enzymes in the environmental industry to benefit an ecosystem by creating/finding enzymes that would cancel out pollutant. Or find an enzyme that would make plants grow faster or produce more food when photosynthesizing.

Plot Reflection

In my honors biology class, we have begun a new project. We have been split into groups and have each chosen a plot in the forest to observe over the course of the next year. The groups consist of four or five members and each has a specific job to do. There are four possible roles: leader, photographer, naturalist and arborist. The leader is in charge of the group’s wiki-space page and delegating tasks to the group. The photographer takes a visual documentation of the environmental growth and changes in the plot over the course of the school year. They will photograph and take videos of both the creatures that live in the plot and the group hard at work. Eventually, the video clips and photographs will all be compiled into one film in the spring. It’s the naturalist’s job to record, collect and identify various organisms found in the surrounding area of the plot site. The arborist identifies the trees within the plot and measures the growth of the young trees. I am the leader of group number 4. Our group’s name is set, which means ‘3’ in Korean. The other group members are: Madeleine, the photographer; JB, the naturalist and Alexandre, the arborist.

We have plenty of trees for Alexandre to study. All the orange flags mark the baby trees.

Our plot site is the closest to the road out of all of the groups in our class. However, the road cannot be seen from our plot. What you can see is the gate separating the forest from the road. You can also clearly hear cars and trucks passing by. In our plot, there is a large, rotting, fallen tree. It is covered in moss and shelf mushrooms. A colony of ants lives within the log and eats the mushrooms. The ground is thick with dead leaves and acorns from the surrounding oak trees. The creatures hiding beneath the leaves mostly consist of large spiders and the occasional ant. Within in the center of the plot is a gathering of over 40 baby trees. All of the trees, both young and old, have leaves that have either fallen off or are living their last days. The day we visited the forest and staked out our plot was just after a plentiful rainfall. As we all know, that’s prime condition for mushrooms. We found some fascinating fungi, including a purple mushroom.  

One thing I really appreciate about this project is its longevity. I think that being able to actually watch the plot’s changes from autumn until spring will be incredible to observe. I love that we’ll be making a video at the end of the project that will serve as somewhat of a digital time capsule. Looking forward, I see my group’s biggest obstacles being organization, time and focus. However, if we continue on the path that we started on a couple days ago, this is going to be a great year.