BI 369: Plant Physiology (2018W)
TA: Samantha Mulholland
Lab 1. Water Relations of Cells and Tissues
Date: January 10th, 2018
Nikhil Thomas 140598170
Hiba ElMiari Simran Deol Rhys Mcintyre
154160020 140594560 130952590
A (wide open)
C (nearly closed)
41% were open, the majority 59%, are closed
51% were open, meaning majority are open
46% were open, the majority 54% were closed
87% of the stoma, were closed
(KCI + ABA)
95% of the stoma,were closed
Table 1: The statuses of stomata from the lower epidermal peel of a bean plant after 5 different treatments were performed on it.
In the experiment, lower epidermal peels from a bean plant were taken and subjected to different treatments. After these treatments were conducted it could be determined that a majority of the stoma were closed. In the first treatment the epidermal peel was subjected to KCI and place in the dark. Approximately 2 stomata were wide open, 12 were open, 9 were nearly closed and 7 were completely closed. 59% of the stomata were closed after the treatment, while 41% were open. This data makes sense because since the epidermal peels were placed in the dark, the stomata will close since the potassium ion concentration in the guard cell when there is no sunlight present. In the second treatment the epidermal peels were treated with KCI again but this time the treatment was left in the light. This resulted in 2 stomata that were wide open, 16 that were open, 8 that were partially closed and 9 that were fully closed. 51% of the stomata were open, while the other 49% were closed. This makes sense as since the peels were in sunlight, the guard cells will have a high potassium ion concentration and thus will remain open. The third treatment was done through mannitol. In that treatment 0 stomata were wide open, 21 were open 5 were partially closed and 19 were closed completely. In this treatment, most of the stomata, about 54%, were closed. This also makes sense as mannitol is a hypertonic solution and would cause the cells to shrink. This is because when cells are placed in hypertonic concentration, the solute concentration are higher outside the cell and so water rushes out of the cell. In the 4th treatment, ChCl, resulted in 0 wide open stomata, 5 open stomata, 15 nearly closed stomata and 20 fully closed stomata. This meant that 87% of the stomata present in the lower epidermal peel were closed. This is since ChCl is a quaternary ammonium salt, meaning that it will create a hypertonic solution, causing the cell to shrink due to the water leaving the cell caused by the difference in concentration gradient. The last treatment was a combination of KCI + ABA and also conducted in the light. This treatment resulted in 0 wide open stomata, 2 that were open, 10 that were partially closed and 30 that were fully closed. That meant that the 95% majority of the stomata were closed. ABA is a hormone that is released usually at times of drought stress. So in order for the plant preserve water, ABA causes the stomata to close in order to retain what ever water is left in the plant until the drought stress period is over.
Table 2: Morphology of Stomata from Lower Epidermal Peel of a Bean Plant after 5 different Treatments
In the first and second treatment, the black stippling represents the potassium ion location on the stomata. The treatments that caused the stomata to close had a higher concentration of potassium ions outside the cell. In the fully closed stomata the potassium ions were not found inside the stomata. In the first treatment that was held in the dark there is lack of potassium ions present in the stomata compared to treatment 2 since, the stomata open to photosynthesize in the light but close in the dark to conserve water.
2. cytochemistry is the, chemical reactions and compounds found in living cells that are studied microscopically. Some methods of cytochemistry are, affinity cytochem, dual-immunocytochem, insitu-hybridization, and immunogold detection. Affinity cytochemistry is the detection of ligands bound to target cells. Dual-immunocytochemistry identifies more than one product of a cell at the light microscopic level. Insitu-hybridization is used to detect mRNA in a cell. The last method that was found immunogold detection is used to detect 2 or more antigens in the electron microscopic level. Cytochemistry has been proven very useful in many ways. It was used in diagnosing acute leukemia in a study that was conducted recently. This was done by finding potassium ions in the cells using cytochemistry methods. Using a staining method, cobaltnitrate, was used to confirm the location of the potassium ion movement under the different treatments conducted in the study. Overall cytochemistry has application within a lab setting as well as medicinal purposes.