Beet Lab Report

And finally into test tube 3, I pipetted 1.0 ml turnip extract and 4.0 ml of water. The contents of test tube 1 was poured into a spectrometer tube and labeled it “B” for blank. “B” tube was now inserted it into the spectrometer. An adjustment to the control knob was made to zero the absorbance reading on the spectrometer since one cannot continue the experiment if the spectrometer is not zeroed. A combination of two people and a stop watch was now needed to not only record the time of the reaction, but to mix the reagents in a precise and accurate manner. As my partner recorded the time, I quickly poured tube 3 into tube 2. I then poured tube 2 into the experiment spectrometer tube labeled “E” and inserted it into the spectrometer. A partner then recorded the absorbance reading for every 20 seconds for a total of 120 seconds. After the experiment, a brown color in the tube should be observed to indicate the reaction was carried out. Using sterile techniques, any excess liquid left was disposed

This lab was performed to test the permeability of the cell membrane of a beet using various and extreme temperatures (high and low). The prediction of this lab is testing how much stress the cell membrane can withstand under different polarities and strengths of bonds using our understanding of the fluid-mosaic model. A spectrophotometer was used to calculate the absorbance of each variable after the beet was placed in each environment. When the lab was completed, the data stated that under each different reactant and condition the cell membrane showed multiple changes in tolerability of the beets.

The cell membranes are the utmost essential organelle that surrounds all living cells. Its purpose is to control what goes in and out of the cells and is accountable for the various other properties of the cells as well. The nucleus and other organelles also have membranes that are practically indistinguishable. Membranes are organised in a mosaic arrangement, comprised of carbohydrates, proteins and phospholipids. This can be seen in Figure 1. The objective of this indirect examination is to study the causes of various solvents and conducts on live beetroot cells. The reason why beetroot cells have been selected for this experiment is because they have a big membrane-bound central vacuole, as seen in Figure 2. The red colour anthocyanin, which provides the beetroot its bright colour is located in the vacuole. The cell membrane encloses the whole beetroot cell. The anthocyanin cannot leak out if the membranes stay unharmed. The red colour can escape if the membranes are hassled or broken.

Therefore, more of the red pigment in the beetroot would leak as the lipids control the substances that enter and leave the cell membrane.

The cell membrane (Plasma membrane) functions to provide cell support, cell stability and control entry and exit of materials from the cell. This study was conducted to test the effects of environmental conditions such as the on beet root cell membrane (Beta vulgaris). Five trials using varied pH concentrations were tested and absorbance rates were monitored. The experimental results showed that the protein function decreased sequentially when the pH decreased. This allowed the betacyanin dye to leak out which created the color that was needed to determine the intensity and therefore the effect of the circumstances. This supported the hypothesis that the more acidic or basic the environmental condition around the beet cell, the more permeable the, membrane indicated by color intensity. Pigment leakage in the solution was analyzed by using a spectrophotometer.

The Effect of Temperature on the Permeability of Beetroot Membrane Analysis The graph shows the colorimeter readings increase as the temperature increases, they increase by the most at higher temperatures. This is shown by a smooth curve. This means that the beetroot samples release more dye at higher temperatures.

In the beginning of this experiment, our TA added water, salt, and 75/25 hexane/acetone to spinach leaves to a blender and blended the mixture to assume equal amounts for each group and to avoid erros if each student had to do the blending. The addition of the water to the mixture allowed the it to separate into a distinct organic layer after being run in a centrifuge, which was available to be collected at the top of the centrifuge. Salt reduces solubility, which will force the organic parts of the mixture (the desired pigments for example) to separate into the organic layer at the top. Lastly, 75/25 hexane/acetone is added because this is a moderately polar solvent and will useful for both the non-polar and polar pigments present within the spinach leaves. A mixed solution of hexanes and acetone must be used because acetone is very polar, while hexane in very non-polar, and the spinach leaves contain both non-polar and polar pigments in them that are important in the extraction and for further analysis. The mixture was placed in the centrifuge so the solids in the mixture (mostly cellulose) could be separated from the liquids into separate distinct layers for further extraction and testing. In the tube, the organic substances separated into the top layer, whereas the water layer remains at the bottom of the tube below the solid layer made up of mainly cellulose.

The results increase steadily between 0°C and 45°C. There is a steep increase between 45°C and 65°C. This is the point when the proteins in the cell membranes are denatured causing gaps to form in the membrane, thus allowing more red pigment from the beetroot to diffuse into the distilled water.

The volume of a small test tube and a thin-stemmed pipet were determined in this section of the lab. Water was poured into a small test tube until the water reached the very top edge of the test tube. The test tube was then emptied into a plastic 25 mL graduated cylinder and volume was measured and recorded into data table 3. A think-stemmed pipet was completely filled with water. Drops were carefully counted and emptied into the empty plastic 25 mL graduated cylinder until the water level reached 1 mL. The number of drops in 1 mL was recorded into data table 3. The thin-stemmed pipet had a total volume of 4 mL and that was also recorded into data table 3.

Plasma membranes are the physical barrier of cells, which are selectively permeable to allow the passage of materials such as nutrients, gasses and waste products (Flinders University, 2015). The steroid cholesterol contained in the plasma membrane increases the membrane fluidity at higher temperatures (Blicher et al., 2009). Beta vulgaris contains a pigment called betalain, which leaches out of the tissue when there is an increase in membrane permeability, this causes the solution B. vulgaris is in to turn red (Flinders University, 2015). The aim of this investigation was to determine the effect of temperature on Beta vulgaris plasma membrane permeability.

The aim of this investigation was to determine the effect of ethanol on the membrane permeability using Beta vulgaris. Beta vulgaris contains red pigments called betalain sequestered in vacuoles. The cell membrane is generally impermeable to betalain as this pigment is relatively large and cannot pass through the membrane by diffusion. (123HelpMe.com, 2015) However, by increasing the permeability of the cell membrane, betalain can leach out of the cell and colour the liquid red. The colour intensity of the solution due to leakage of betalain is proportional to the membrane permeability. To quantify the colour intensity, the light absorbance of the solutions containing a Beta vulgaris cube were measured by a spectrophotometer. These measurements were used to analyse the membrane permeability. (Flinders University, 2015)

If a larger range of ethanol concentrations were trialled than Kalant’s (1971) claim could be tested for accuracy, and a trend could be determined to reliably support or reject the hypothesis. Moreover, the ethanol concentrations used differed significantly, thus it was difficult to identify random errors and establish an accurate trend from which the data could be analysed. Many aspects also limited the scientific scrutiny of the results. For example, the B. Vulgaris cubes were rinsed and immersed in distilled water before the experiment to remove surface betalain. Depending on the time periods these occurred, the water could have hydrated and increased the membrane permeability of the cubes to varying degrees (Disalvo et al, 2008). Consequently, these would skew the results, as they can no longer be attributed to the ethanol concentration. Alternatively, depending on how well the cubes were rinsed, some surface betalain may have adhered and further coloured the solution, such as that for Treatment 1. Additionally, the time in which the B. Vulgaris was immersed in the treatments may have not been long enough for the betalain to leach completely in Treatment 2, but enough for Treatment 1 to leach it’s maximum betalain, resulting in its higher membrane permeability. Moreover, only the spectrophotometer was used to indicate membrane permeability, which could have limited the data, as if the values were incorrect due to improper calibration of the machine, no other data was available to analyse and compare permeability. The treatment solutions were also not personally prepared and in bulk, hence, the vials may have been incorrectly labelled, resulting in the unexpected results in Figure

The reason why we got these results can be explained, when alcohol interacts with the cell membrane is affects the normal formation of the lipid chains that form in a bilayer, it is believed that alcohol binds underneath the charged head of the lipid and displaces water that is originally there [1] this breaks up the membrane allowing more of the red pigment to diffuse out of the beetroot. [2] The ethanol forms temporary bonds with the phospholipid heads in the bilayer as they are opposite dipoles causing the phospholipids to move out of place causing gaps to form which allows large molecules such as betalain to diffuse out of the cell. As well proteins, like enzymes, can become denatured by the ethanol due to the same affect as with the phospholipids this can disrupt the hydrogen bonds, which maintain secondary structure. The negative ethanol molecules cause the bonds between the amino acid chains R-groups to

There are six main classes of phenolics found in grapes: catechins, procyanidins, anthocyanins, flavonols, hydroxycinnamates and hydroxybenzoates. The difference between red and white wines is due to the different types of phenolics in the two beverages. The simple phenolics - the hydroxycinnamates and hydroxybenzoates - occur in the flesh of the berry and so occur in both red and white wines. The other more complex phenolics, known collectively as flavanoids, occur in the skin, seeds and stems and so occur mostly in red wines. The procyanidins are also known as condensed (or non-hydrolysable) tannins, and it is these that give wine most of its astringency. A further group of tannins, the hydrolysable tannins, are found in wine that has spent time in oak barrels. These tannins are also astringent, and are complex esters of glucose and gallic acid. Anthocyanins are the commonest source of colour not only in grapes but in all flowering plants. Their color depends on the number of hydroxyl groups on the molecule and can range from orange through red to purple.

The major drawback of Folin- Ciocalteu (FC) method is the ability to react with the reducing compounds in red beets such as ascorbic acid and nitrogenous substances especially Dopa (3,4-dihydroxyphenylalanine), thus providing higher values of phenolic compounds in the extract. Moreover, the main component betanin of red beet is structurally similar to Dopa(3,4-dihydroxyphenylalanine) which may contribute to the higher values using FC spectrometric estimation (Kugler et al., 2012).