Saturday, December 27, 2014

Cell communication lab

Purpose: The purpose of this experiment is to study yeast cell communication.  We will study the differences between three different party dishes which will contain "a" type, alpha type, and mixed.  The purpose is to study the differences between the cells and the number of cells and how they act.

Introduction:  Yeast cells have the ability to reproduce sexually as well as asexually.  There are two types of yeast cells, alpha and "a" type.  If these two are isolated then they will reproduce asexually. When reproducing asexually they make a growth that is called a schmoo. In order for sexually reproduction to happen these two types must be mixed together.  When these two are mixed a haploid cell, asexual, quickly turns into a gamete cell, sexual.  Once they change they grow toward eachother finding a mate a reproduce.

Methods: Take three agar plates and label them alpha, "a", and mixed.  Then label your cultured tubes the same as it is appropriate. Add 2 ml of sterile water to each cultured tube then add some of each yeast type to the appropriate tubes. Take that solution and put 5 drops of each on their designated plates.  Then observe these under the microscope over fourt time periods.  Record how many cells are in each field as well as how many schmoos.
Purpose: The purpose of this experiment is to study yeast cell communication.  We will study the differences between three different party dishes which will contain "a" type, alpha type, and mixed.  The purpose is to study the differences between the cells and the number of cells and how they act.

Discussion: In our experiment we were trying to understand cell communication through yeast cells communicating.  In our experiment we used a cells and alpha cells separately and a mix.  When cells reproduce asexually they become budding haploids.  This can only happen with cells of the same type.  When there are a mix of a and alpha cells schmoos can be formed.  In our experiment we found that only schmoos were formed only in the mixed group because schmoos can only be formed when one cell sends out a specific chemical messenger to the opposite cell.  We also found in our experimental group that the cells can travel great distances in order to mate.  In our experimental group we place the different types of yeast on opposite sides of the petriadish and by the next day the yeast cells had formed schmoos.  

Conclusion: Cells of the same type form budding haploids. If you mix the different strains the cels will attempt to mate by forming schmoos. This is due to a signal sent out by each cell. If it senses an opposite strain nearby it signals to that strain. The strain receiving the signal will respond by forming a schmoo. Our experiment found that they can do this across large distances also.

Sunday, December 14, 2014

Photosynthesis Lab

Purpose: in this lab we were trying to test the rate if absorb acne and transmitance of light in chloroplasts.  Chloroplasts only absorbs certain amounts of light and we tried to test the amount absorbed over time.  Our dependent variable was time and our independent variable
of our experiment was the rate of absorbance for each of our cuvettes

Introduction: Photosynthesis requires light and co2 to work and the biproducts of photosynthesis is o2 and glucose. If there is deprivation of co2 the rate of photosynthesis will drop.  This would only occur in a closed system.

Methods: First we took five cuvettes, one was filled with just water, two with unboiled chloroplasts, one with boiled chloroplasts, and one with no chloroplasts.  All of these had DPIP in it except for the first cuvettes which had just water. One of the cuvettes with unboiled chloroplast had aluminum rapped around it. We used the cuvette filled with water to calibrate the spectrometer, then we took initial readings of all the other cuvettes.  We then exposed the cuvettes to light for five minutes and took the readings, we repeated this two more times. We also used a large water sink bath to prevent heat from being a factor.



Graph and Charts: 

Discussion: The cuvette with just water, dpip, and the phosphate saw no increase in photosynthetic productivity due to the fact that there was no chloroplast to process the light. The cuvettes with chloroplast that was on ice saw a slow decrease in photosynthetic productivity. This was expected because chloroplasts use the light to create O2 through the light reactions of photosynthesis. While it was not natural light, some of the UV rays are still able to be used by the chloroplast for photosynthesis. The cuvette that was wrapped in aluminum foil, still put in front of the light, and still had chloroplasts and dpip saw a sharp decrease in photosynthetic production because there was really no light going in and so all the light was used up. While it was expected that the light from the lamp would provide enough UV for photosynthesis to occur (which it did) it was surprising that the rate of photosynthetic production declined in all of our cuvettes except for the one with no chloroplast, which saw no decrease or increase in photosynthetic productivity. This was because since there are no chloroplasts, nothing could be photo synthesized. The dpip would turn from blue to colorless if it was used by the chloroplast, which it was. It did not turn from blue to colorless in the cuvette with the boiled chloroplast becasue since the chloroplasts were denatured the dpip couldn't be reduced and used. 


Conclusion: How is it possible that there was no increase in absorbance? The chloroplasts need CO2 to restart the cycle. Over time in a closed container there was no CO2 being made. Only a lot of oxygen. The oxygen could not keep the rate of photosynthesis going so there was a decrease in light absorbance.

Sources: http://www.answers.com/Q/What_is_the_effect_of_boiling_chloroplasts_on_the_subsequent_reduction_of_DPIP
Charles Filipek

Monday, December 1, 2014

Cellular respiration

http://thezuluwarrior.blogspot.com/2014/11/cellular-respiration.html

This has been shared from my personal blog. sorry for the inconvenience Mr. filipek