Cellular Respiration Lab

Purpose:

The purpose of this experiment was to see whether germination and temperature affect the amount of CO2 released. We were testing to see if germination on (barley) seeds would affect their cellular respiration process and eventually cause them to not produce CO2. The independent variable was whether or not the seeds were germinated and if the temperature changed. The dependent variable was how much CO2 was released. We wanted to see how much of a difference there would be between the four groups we tested out.

Introduction:

The lab we were about to conduct dealt with the process of cell respiration. Cell respiration is the series of metabolic processes by which living cells produce energy through the oxidation of organic substances. This conversion is done to benefit organisms because it converts chemical energy into a form that can be readily used. This is shown through the following equation:

C6H12O6  +  6O2 →  6CO2  +  6 H2O  +  Energy (ATP)

It is a fact that all animals and plants go through this process of oxidizing glucose for energy. Therefore, barley seeds with go through this process as well. We know that different variables may alter or affect carbon dioxide product during respiration (such as germination and temperature).

Methods:

For this lab, we would be performing the same practical procedure a multitude of four times, each with a different barley seed. We would begin with germinated barley seeds, twenty five of them that had been wrapped in moist paper towel for a period of time. Those seeds would then be blotted dry and the temperature of the room would be taken for comparison of a later trail that would compare the effect that temperature could have on the CO2 release of the seeds. With the room temperature recorded and the germinated seeds blotted dry, all twenty five would be placed into a carbon dioxide reading chamber which would then be connected with our LabQuest to graphically show the amount of CO2 being released from within the chamber. In order to get an accurate reading of the carbon dioxide being released from the germinated seeds, they would be left in the chamber to collect data for a minimum ten minutes. Once the time had passed and data for the graph on the LabQuest was present, the seeds were taken out and put into a beaker of cold water that had ice in it as well. Whilst the germinated seeds cooled in the cold beaker water, the CO2 probe that was taking carbon dioxide readings in the chamber was to be fanned with paper for a minute total and the chamber itself was washed out with water and then thoroughly dried with paper towels. Once the chamber was dried, we were ready to begin the alteration to our testing trials which would then provide us with data to see the effects that temperature has on the release of carbon dioxide from our seeds. The germinated seeds that we had put in the ice beaker would then be taken out and blotted dry with paper towel and then placed in the carbon chamber to begin collecting data on our LabQuest for ten minutes just as we had done before with the room temperature germinated seeds. The very same processes would be again repeated for our twenty five non germinated seeds as well as for our control group of glass beads, the only exception being that the glass beads would not be chilled in a beaker of cold water. The graph that we collected from all trials would be stored on our LabQuest and we would calculate the slope of the graph for each trial run for comparison. Once all the runs were completed we compiled the graphs together so that the differences between all of them would be visually easier to see.

Non-Germinated barley seeds

Germinated barley seeds

Testing for CO2 release

Checking temperature change

Data:

Graphs:

Discussion:

Our graphs show that for the non-germinated barley seeds, as time went on, the release of CO2  decreased. For the germinated seeds, as time went on, the release of CO2 increased. For the germinated seeds in cold water, as time went on, the release of CO2  decreased. The control group (glass beads) had no change in CO2 release, and it's slope was 0.

The data for germinated seeds in cold water was very similar to the non-germinated seeds and for both the release of CO2  decreased. However, the germinated seeds increased in the release of CO2  and the control group remained constant.

The amount of CO2 produced by the germinated seeds in cold water and the non-germinated seeds was about the same. This showed that both germination of the seeds and temperature change have an effect on the amount of  of CO2 released.

What we did well in this lab was that we had an accurate indication of both variables (germination and temperature change). However, what we did badly in this lab was that our control group data was not helpful. It was probably tampered with, so it's information is almost useless to compare to the other test groups.

The validity of our data is not very good. Our data was too low compared to other in the class who also did barley seeds. It was off by a good 0.12-0.24 ppm/s. It was double what we had. However, our data was at a reasonable range, so it wasn't completely off. Also, when compared to the average at room temperature Mr.Filipek gave us, our data wasn't too far off.

Going off what we talked in class, we thought that temperature and germination would affect the barley somehow. Obviously the groan shows that these variables do affect the amount of CO2 released, so we were able to support this hypothesis.

Conclusion:

The question we were trying to answer was does germination and temperature affect the amount of CO2 released?

Obviously they do affect the outcome, and our data supports it. For instance, the slopes between the germinated seeds in cold water and the non-germinated seeds were very similar. The amount of CO2 produced was also very similar between the two. Also, based on the control group (the glass beads) given to us, the germinated seeds at room temperature data was very close to that average.  

What we did wrong in the lab was that we messed up the outcome of the control group. We believe the glass beads test was tampered with, whether someone knocked it over or it was left out too long. If we were to do this experiment again, we would fix that part and do multiple trials to make sure the first trial was not faulty.

Diffusion Lab

Purpose:

1A- In part 1A, we tested to measure the diffusion of small molecules, glucose and starch to be more specific, through dialysis tubing, which is an example of a selectively permeable membrane. In this experiment, the only variable we would have control over would be in the amount of solution in the beaker and in the dialysis bag. We would not have control over the permeability of the bag, or how much solution would or wouldn't pass through. Then depending on significant color change, we would be able to detect the presence in substances different from what was originally in the two closed solutions at the beginning of the lab.

1B- The purpose of this lab is to use the dialysis tubing to the determine the relationship between the solute concentration (sucrose) and the water movement through the process of osmosis. In the lab, the control variable is only  the concentration of the solution in the dialysis bag and the  beaker. The percentage change in mass of the dialysis tube is depended on how long the dialysis tube have been sit  in the beaker. Over time, this will cause the dialysis tube to increase or decrease. In this lab we are trying to find out if the mass of the dialysis tube increase or decrease when it have been sit in the beaker for a period of time.

1C- the purpose of this lab to find out the water potential of potato cylinders. We used a potato to cut 5mm potato cylinders and weighed them. We then put them in a sucrose solution and let them sit over night. The next morning we took them out of the sucrose solution and weighed them again. We took the difference in weight and found the percentage of change.

Introduction:

1A-Diffusion occurs when a substance attempts to equalize. The concentration gradient that a substance will always follow in diffusion is the movement from a high concentration gradient to a low concentration gradient, until equilibrium occurs. For example, if a cell is placed into a solution that has a higher percentage of water in the solution than inside the cell, water will move into the cell until there is an equal percentage of water both inside and outside of the cell. But sometimes a membrane will only allow certain molecules to pass through it; this is called a, as the function states, selectively permeable membrane. In addition, a Benedict's test is used in testing for the presence of glucose. Should a strip change color when submerged into a solution, that would signify that a solution contains glucose within it. A cell membranes permeability is determined by pores in the membrane itself. Depending in the size of the pores in the membrane Denise which molecules can or can't pass through. If a molecule is larger than the openings of the pores in the membrane then it will not be able to pass through.

1B-The process of osmosis occur when water need to move from lower solute concentration to a higher solute. In simple term, when there is more stuff in or outside of the cell, water tend to move to the area that have more stuff. This process is very crucial to determine the balance of cell and it environment or the death of a cell. Osmosis consist of three different type of environments: isotonic, hypertonic, and hypotonic. In isotonic solution, the stuff outside the cell is equal to the stuff inside the cell. In the case of the animal cell, the cell under this condition is stable. Unlike animal cell, plant cell become shriveled and cause the plant to not standing upright.  In  hypertonic solution, there is more stuff outside than inside the cell. This would cause the water to leave the cell faster than it can enter into the cell. Both plant and animal cell under this condition will die. In the hypotonic solution, there is more stuff inside the cell than outside the cell. Water in this solution will enter the cell faster than it can leave the cell. The animal cell is unstable in this solution and eventually it will burst. With a lot of water rushing into the cell, the plant cell benefit from this solution in that the cell will become more turgid and the plant will stand upright. In this lab, we would expect the potato core to increase in mass under the hypertonic solution and decrease in mass under the hypotonic solution.

1C- Water potential is when a molecule with a lot of water give up water to its surroundings to try creating an equilibrium state. Water potential occurs becuase of two reasons, one reason is when the pressure raises the water potential and the relative concentration of the solute. The pressure rises because if water leaves the cell the the cell will shrink and if the water enters the cell the cell will explode.  

Methods:

1A-Diffusion occurs when a substance attempts to equalize. The concentration gradient that a substance will always follow in diffusion is the movement from a high concentration gradient to a low concentration gradient, until equilibrium occurs. For example, if a cell is placed into a solution that has a higher percentage of water in the solution than inside the cell, water will move into the cell until there is an equal percentage of water both inside and outside of the cell. But sometimes a membrane will only allow certain molecules to pass through it; this is called a, as the function states, selectively permeable membrane. In addition, a Benedict's test is used in testing for the presence of glucose. Should a strip change color when submerged into a solution, that would signify that a solution contains glucose within it.

1B- To set up the lab, the six dialysis tube need to be fill with six  solution of different concentration of sucrose. Before doing anything else, the initial mass of the tube need to be weighted. The dialysis tube then need to be place in a beaker that have the same concentration of sucrose. In the next step, the dialysis tube need to be sit in the beaker for 30 minute. After the dialysis tube have been sit for 30 minute, the dialysis tube need to be weight to see if there have been a change in mass of the dialysis tube.

1C- We started out by cutting long cylinders out of the potato with a cork borer. We did this twenty-four times to have 4 chunks for each solution. Then we weighed the mass of groups of four and recorded it, so that later we could see if any diffusion/change occurred. We put the groups of 4 into the sucrose solutions (ranging from distilled water to 1 M of sucrose) and covered them with plastic to prevent any evaporation. We let it sit for thirty minutes so that the sucrose could diffuse from the solution. After that, we took the potato chunks out and weighed them once more to see how much they changed. We recorded the weight change as well and calculated the percentage change. This let is see how much solution diffused in or out of the potato.

Data:

1A-

1B-

1C-

Graphs and Charts:

1B-

1C-

Discussion:

1A-For this part of the experiment, we only had to fill out a chart with whether or not glucose was present and the color of the solution. We were able to find out that after waiting 30 minutes for the diffusion to happen, glucose was present inside AND outside the bag. We tested this out by using Benedict's solution (which is very accurate). The validity of our results is also very high because we discussed as a class what the results for the chart we're supposed to be. Because of that, we compared out graph to what was up posed to be correct and found no inconsistencies with our data. We were also sure of this because our results also made sense; it was what we had predicted would happen. Because there was diffusion of glucose out of the bag, since the membrane was selectively permeable, it was only appropriate that the outside solution would test positive for glucose. We could always have more trials for more accurate results, but since it was easy to test, our results were accurate and fit our hypothesis. 

1B-The data stable showed that the more molarity the solution has, the more mass the bag gained. It was pretty constant throughout the experiment that this trend followed. The only outliers were the .2 M and the 1 M solutions. Both the data table and the graph show that these sections don't seem to fit because if the dramatic drop in weight. Also, it doesn't fit our hypothesis that they should gain, not loose, weight as the molarity increases. We think something might've gone wrong with those bags which is why we try to use the class data to compare its validity. Obviously our section brought the class average down, so we can't completely trust that part. However, we can look at other tables' outcomes and compare there. As we predicted, the more the molarity they had, the more it weighed. Even though our experiment came out a little bad, looking at others' results helped conclude that out hypothesis was correct. In the future, more trials of each part would obviously help since ours came out faulty. Also, more time is needed for the bags to be left in the solution for more diffusion to occur. 

1C-The data table shows that when there is 0 M (distilled water) to .2 M  of sucrose, the solution diffused into the potato cylinders. Once they were in .4 M to 1 M of sucrose solution, the potato cylinders diffused starch out to the solution. This is proven by the data because the percent change in mass is positive from 0-.2 M of sucrose and negative from .4-1 M of sucrose. This make sense because more concentration in the solution means more diffusion will have to occur to reach equilibrium. The data table shows that there is a consistent decrease in percent change in mass up until the .8-1 M of sucrose. It might just be a kink in the solution, but other than that the data is pretty accurate. The higher concentration the solution is, the more diffusion will occur to reach equilibrium. This supported our hypothesis that higher water potential want to go to lower water potential. We also know this data is valid because our percentages were very close to the class average. It would be more valid if we had more trials for each concentration of the sucrose solution and if we let the potato cylinders sit in the solutions a lot longer than thirty minutes. Overall, it was a successful experiment.

Conclusion

1A- in our experiment, the goal was to measure the diffusion going on between the starch solution in the dialysis tubing and the surrounding water.  As seen in our chart, after we tested each solution with a Benedict's test , the mix of iodine and distilled water entered the bag while the glucose/starch solution left the bag. We knew this because of the different colors it turned according to whether or not there was glucose present in each solution which there was at the end because some of the solution inside the bag left and was able to bypass the membrane. 

1B- In the experiment we concluded the higher the molarity of a substence the greater the osmosis. When plotting the points on our graph we found out that we had two points wrong compared to the class average. We believe they were wrong because we didnt let them sit in the water long enough. 

1C- We wanted to prove that water will move from an area of  higher water potential to one with lower water potential. Therefore, the lower the concentration of sucrose solution, the more it will diffuse into the potato cylinders. Our data supported this seeing as the percent change in mass is positive from 0-.2 M of sucrose and negative from .4-1 M of sucrose.

Onion Cell Plasmolysis (1E):

Purpose: The purpose of this lab is to investigate what happen to onion cell is put in the hypotonic, isotonic, and hypertonic.

Hypotonic:

In a hypotonic solution, water enter the cell faster than it can leave. This is to the fact that there is more solute inside the cell than outside the cell. Because to this, the size of the cell expand. In an animal cell, the cell would explode. Since this is the onion cell, the onion would become turgid and tough. Hypotonic solution is most suitable to plant like onion.

Isotonic:

In this solution, the amount of water that enter and leave the cell is equal. Because there is no excessive in water entering the cell, the onion cell actually wilt. This mean that the onion is not as turgid as the cell in the hypotonic solution.


Hypertonic :

In this solution, the water leave the cell faster than it can enter the cell. This happen because there is more solute outside the cell than inside the cell. Through the process of osmosis, the water leave the cell. The hypertonic solution is not very suitable for the onion cell. Because so much water is leaving cell, the onion cell significantly shrink in size that there isn't much content left in the cell and the cell die.

Restoration Ecology Field Trip, Firas

I believe that the field trip to Glacial Park was educational and fun. While there we planted seeds, watered plants, and we cut down plants that are harmful to the native species. More communities should get together and help the native species. Most forest are being harmed by invasive species, so it it is our job to protect the native species that should be growing in our forests. By restoring native plants, we bring back animals that have left the forest becuase of lack of food. Another reason we should restore is becuase when animals come back they are able to reproduce  which can help with species becoming endagered.

Restoration ecology field trip, Naomi

Naomi's Reflection 

I personally felt that the restoration trip was something that was not only impact full on the area we were helping to restore but, on myself and hopefully my peers as well. The process, I learned, is an arduous one and there are copious ways in which one can help in restoration. My class and myself was given the opportunity to aid in both biological remediation, being using organisms to detoxify polluted ecosystems by removing harmful substances from said ecosystem, and biological augmentation, being using organisms to add essential materials to a degraded ecosystem.
The first was done by our physically removing invasive species such as thorn brush that is beginning to take over the endemic species of plants native to the area. Using various tools and brute strength powered only by the love to learn, it was down in the brush we went to do our part in spreading up ecosystem to get back into its natural state. The removal of the invasive species was pertinent to restoring the area as the invasive species is harmful to the native plants and inhibits their natural growth and contribution to the ecology in that area.
All our work down in the thorns and branches paid well as we managed to
clear a good section of the area which will help in the increased remediation of the ecology.
The trip also allowed us to participate in our share of biological augmentation. We were given acorns to plant around a field as well as buckets full of water to water budding trees in the surrounding area. We then scattered about and dug up as many new homes for possible future trees to inhabit. Though we were given a generous amount of acorns, not all will flourish which is why the great number of seedlings were planted, to ensure a higher rate would survive at the least.
Restoration ecology is so critical to the survival of species plant and animal alike. It impacts our daily lives as well. Species that begin to inhabit conflicting areas non-endemic to themselves disrupt the natural habitat and creatures native to that area much like the new Asian carp that is becoming problematic in the Great Lakes. Nature requires balance and when that balance is thrown it should be our responsibility to restore back to its natural state. Restoration ecology is an ongoing effort and as the field director informed us, it will require the efforts of multiple generations but the product is something worthwhile.

Restoration ecology field trip, Billy

Billy's Reflection

It is awesome to go to Glacial Park and actually do some real science. I don't have that opportunity in my other science class. In Glacial Park, I get to do many thing. I water the plant and plant some acorn into the ground. I also have the opportunity to remove some invasive species and allow more native plant to grow. At first I thought that this is actually a lot of work. I eventually learn the important of why I am doing this. I am doing all of this because I wanted to learn more about restoration ecology. Restoration ecology is crucial. Without it many organism would died. There are many benefit to restoration ecology. It help by reintroducing the native plant to the area. An example of this is by planting an acorn into the ground. Through restoration ecology, invasive specie can be remove so that the native plant can have some to grow. I really like to spend time outside and explore nature. Restoration ecology is way to fix thing that other people have done wrong and appreciate what nature have to offer everybody around the world. In the end, all road will eventually lead to detritus. Matter will then recycled itself and restore the environment to the way it is. This is how nature operate. It is just a biological soup of mixture that will lead to something new and what is to come.

This is the process of planting acorn into the ground

This is the process of removing invasive specie

Restoration ecology field trip, Danica

Danica's Reflection

Last week, I had the opportunity to visit the McHenry County Glacier Park. The first thing we did was water plants that were planted by last year's students who went on the field trip. After irrigating the plants, we planted acorns to help speed up the seeding process that would naturally happen through chipmunks or squirrels. The second half of our visit consisted of helping take out unwanted trees and shrubs in order to clear out some area. At first it seemed counterproductive, having to cut down and remove species in order for more things to grow, but I soon learned that that's a natural process. We cut down smaller trees that were overcrowding the bigger ones as well as weeded and trimmed. We learned that this process allowed new, native plants to flourish and as a result, attract more native wildlife. How do these creatures know to come back? It's not certain, but we do know that because of our hard work clearing out that part of land, that we would be able to attract different kinds of creatures. Looking at the pictures was very satisfying. Knowing that we helped Mother Nature speed up a process was very fulfilling. The trip as a whole served as a good hands-on learning activity as well as a benefit to nature itself.

Restoration Ecology Field Trip, Steph

Steph's Reflection             

This field trip was very eye opening. It felt weird killing off so many living things, but it was nice to know that by getting rid of the invasive plants, we can help good and healthy ones grow. It's very rewarding to know all our cuts, bruises, and sore backs resulted in a more beautiful place. Ecology restoration is a strange concept because killing one thing to help another grow seems wrong, but it's still very necessary. Considering Mother Nature takes a long time to do the restoration process herself, we need to help speed up this process as much as we can to help many other organisms that benefit from this be able to live. It takes a lot of work and time, but it's more efficient than if we let it do it itself. Being able to have good plants brings back their native animals that can help with the cycle of life. However, sometimes the restoration takes too long even with human help, so it can be destructive and not as helpful as people would like it to be. Over all, ecology restoration is a very good thing for our environment since it helps animals and plants be able to survive sooner rather than later making the world a more beautiful place to be in.

Before restoration

 

After restoration