Cell Communication

Purpose

The purpose of the yeast cell communication lab is to see the rate at which yeast mate. We needed to record the number of yeast at each stage of the cell cycle. We also calculated the percentage of yeast at each time point and we recorded our data. We had three cateroiges to record. They were the alpha culture, the A culture, and the mixed culture. We were looked for single haploids cells and building haploid cells.

 

Introduction

Well to introduce this lab, its cell communication. The definition of cell communication is indepth in biophysics and biochemistry to identify different types of communication methods between living cells. Some of the methods include cell signaling. This lab had a focus on cell communication. Cell communication happens between cells when cells secrete chemicals to attract other cells. Cells are able to communicate by direct contact, local or long distance signaling. 

Method

In our lab, we cultured yeast in both solid and liquid mediums. The purpose of this lab was to determine how cells communicate with each other. We concluded that yeast cells cannot swim to other cells to communicate with them. We tested production of offspring during the time increments of 5, 10, 15, and 20 minutes that we set for each sample. A type, Alpha type and Mixed type were placed in their own solid and liquid mediums. They were then placed in an incubator overnight and then the amount of yeast cells were counted. 

This picture shows how we set up the lab. We have a dish for each culture.

We take a swab from the dish.

This is a look at the yeast after a twenty-four hour period.

Discussion

This experiment tested the communication in different types of yeast cells, Alpha type, A type and Mixed type. The only difference between these types of yeast cells are the different genes each specific yeast cell contains. Cell communication happens between cells when cells secrete chemicals to attract other cells. Cells are able to communicate by direct contact, local or long distance signaling. The cells use signal transduction pathways to signal one another. Each cell sends out a signal to adjacent yeast cells letting them know they are ready to mate. If the other cells are able to accept this then the receiving cell accepts the signal, brings it into the cytoplasm where the signal causes a change in the cell that makes it move towards the other cell. Our data showed that after a certain time frame the yeast cell communication slowed down and their ability to reproduce and divide slowed. 

Conclusion

From this lab we learned and got to see yeast mate. Not only did we see them mate, but our lab group saw cell communication. These yeast cells communicated and made a way to reproduce. This lab allowed us to really look hard and exam and determines the routines of how yeast mates in alpha culture, a culture, and mixed culture. The difficulties of this lab were try to capture the images of what we viewed from the microscope. The lab is considered a success because we successfully mated the yeast and took pictures of them as they reproduced.

References

"Cell Communication (definition)." Cell Communication (definition). N.p., n.d. Web. 12 Jan. 2015.

"Cellular Communication (biology)." Wikipedia. Wikimedia Foundation, n.d. Web. 12 Jan. 2015. "LabBench." LabBench. N.p., n.d. Web. 12 Jan. 2015.

Photosynthesis

Purpose

This photosynthetic experiment required us to create different mixtures involving phosphate buffer, distilled H2O, DPIP, and then adding either boiled or unboiled chloroplasts. With DPIP and the varying forms of chloroplasts we tested how fast or if photosynthesis was able to occur, and if photosynthesis was able to occur it simply reduced DPIP into the mixture. By doing this we could also track the percentage of transmitance and absorption with the help of a Colorimeter. 

Introduction

DPIP is used in place of NADP in photosynthesis so if photosynthesis does occur, meaning light does enter the chloroplast and excites the electrons to the electron acceptor, DPIP will reduce from it's blue state to a colorless state. This means photosynthesis did occur allowing the spinach cells to create energy. However, if the mixture remained blue after being exposed to light it means that the chloroplasts were damaged and unable to execute light absorption and thus DPIP remained unaltered. 

Method

We created various mixtures pertaining phosphate buffer, distilled H2O, DPIP and then either no chloroplasts for the control group or the tests which included boiled or unboiled chloroplasts. We added the chloroplasts only  after we poured the solutions into cuvettes which were immediately placed into front of a light source dispersed by a flask of water. We then took measures of light transmitance and absorption of the cuvettes using the Vernier colorimeter. 

Picture /\: Colorimeter

Graphs and Charts

Conclusion: in this pigments and photosynthesis lab we butchered the results. We made the mistake of not placing the unboiled chloroplast until after setting up the test tubes. Which caused us to remake the test tubes. Also we messed up by not placing each of the cuvettes in front of the light at the same time. The cuvettes had been in the light for different amount of times. We had to redo that part to get correct results. We placed each one with same time. The final results were correct and completed this lab making it a success. 

Reference: 

AP Bio Lab 4 - Plant Pigments & Photosynthesis." Bozemanscience. N.p., n.d. Web. 08 Dec. 2014

College Board." AP Central. N.p., n.d. Web. 08 Dec. 2014

LabBench." LabBench. N.p., n.d. Web. 08 Dec. 2014

Photosynthesis." - Wikipedia, the Free Encyclopedia. N.p., n.d. Web. 08 Dec. 2014