We then obsevered the two slides for number of cells as well as for food vacuoles inside a cell using a microscope at times of 0,5,10,20, and 30 minutes. Results The following graphs show the results of this experiment. The tetrahymena sample that was introduced to concentrated tobacco had a lower cell/vacuole ratio than the tetrahymena sample that was not exposed to
Additionally, it was difficult obtaining a piece of rhubarb that was thin and particularly red, therefore the effect could not be best observed in the cells. Part B: Design your own experiment Parts of this practical were taken and slightly altered from the following link http://www.markedbyteachers.com/gcse/science/investigate-the-effect-of-surface-area-on-osmosis-in-potato-tissue.html Aim: To observe the effect different surface area: volume ratios have on osmosis in potato tissue. Hypothesis: If the potato has a larger surface area: volume ratio, the quicker osmosis will take place and the larger the mass will be at the end of the experiment, therefore the difference in mass of the potatoes from the start of the experiment to the end of the experiment will be larger. Additionally, the potato pieces left in a saltwater solution will decrease in mass, whereas the pieces left in water will increase in mass.
Osmosis Egg Lab Report Introduction The experiment revolves around selective permeability of the membranes of de-shelled chicken eggs. The eggs have been soaked in vinegar for about 3-4 days to dissolve its shells, which results in a delicate shell membrane connecting the inner contents of the egg. The shell is selectively absorbent only to water. The solution that is the dissolved in the internal contents of the egg is approximately 18-20% which is the solute concentration.
Osmosis Investigation Aim the aim of this experiment is to investigate the effect of changing the concentration of sucrose on the rate of osmosis in cylinders of potatoes. This would happen by using similar sizes and lengths potato cylinders and applying them to different concentrations of sucrose(0%, 10%, 20%, 40%) in small beakers then measuring the change in mass of the potato cylinders afterwards. Maintaining all variables unchanged such as pH, same size, and a constant temperature. time taken for all potato cylinders will be 30 minutes.
Stomata are pores commonly found on the underside of leaves of a plant (stomata study). These microscopic pores are a passageway for carbon dioxide to enter while at the same time allow water and oxygen to be released (berkley). Plants need stomata as they allow the plant to take in carbon dioxide, a necessary part of photosynthesis (berkley). Plants open stomata by their guard cells located on either side of the stomata (stomata study). These cells can swell up to open the stomata or deflate to close them off (berkley)
For this lab I will be using water and sucrose to demonstrate the rate of osmosis. In this lab I will be exploring how temperature impacts the rate of osmosis by placing pieces of potato of equal size in solutions of different temperatures and observing the change in mass of potato after a given period of time. The change in mass will indicate the rate of osmosis.
In this experiment, beets will be a replica to explore membrane using various extremely low and high temperatures. The roots of beet contain an immense quantity of a reddish color called betacyanin that is located inside the central vacuoles, which are surrounded by a vacuolar membrane called the tonoplast (Biology Lab Manual, 2011). The protein structure of beetroot is very important, because once its interrupted it could lose its purpose and would have to experience denaturation. Cell membranes defend and organize cells, they serve as a fence which means that a few particles can disperse across the lipid bilayer but others cannot. The structure of the cell membrane contains
In hypertonic environments (where there are more solutes outside than inside the cell) cells will lose water. In hypotonic environments (where there are less solutes outside than inside the cell) the cell will gain water. When solute concentration is even both in and outside of the cell there is no water movement so the cell would be in an isotonic environment (Figure 1). Purpose The purpose of this experiment was to find the effect of sucrose solutions on osmosis.
The tube was closed in one end and the test tube was put into a tub with hot water, at about 55 degrees Celsius. The test tube was then filled with water and the base was left empty to mark a baseline. The test tube was then put in a beaker with hot water. In another test tube different concentrations of yeast and corn were mixed. The combinations included 2× yeast; 1× sugar, 1× yeast; 1× sugar and others.
Transpiration is nothing but the the loss of water due to evaporation through tiny pores on the leaf surface. When water is available to the roots they move into the plant through a process called osmosis and this creates a pressure in the root called the hydrostatic root pressure and this pressure forces the water upward but only for a short distance, the rest of the force to push the water up to the leaves is due to transpiration. The water loss is facilitated by the opening and closing of the stomata depending on environmental conditions. A stomata is nothing but the small invisible pores on the leaves. Transpiration is a very important part of the water cycle as it helps in keeping the air moist and this is beneficial to humans.
Biology Design Practical Joshua Edwards What are effects of the volume of a potato and the amount of weight it loses when placed in salt solution? Introduction This design practical uses a potato’s surface area to volume ratio to see what affects it has on osmosis in different concentrations. Osmosis is the movement of water molecules through a cell membrane into an area of a higher solute concentration. The movement goes the way of the solvent with more solute because the lower solute concentration is drifting through balancing the ratio of solute per solvent (En.wikipedia.org, 2018).
Cells can be quite fascinating, especially when one focuses on the similarities and differences of plants and animal cells, the structure and function of the cell membrane, the process of diffusion and osmosis, hypertonic, hypotonic, and isotonic solutions, adenosine triphosphate, photosynthesis, and cellular respiration. Both plants and animal cells have a range of similarities and differences. Animal cells and plant cells fall into the type of cell category called eukaryotic cells. Both animal and plant cells have some similar organelles such as, the plasma membrane, nucleus, mitochondria, endoplasmic reticulum, ribosomes and Golgi apparatus. Although they have a wide variety of similarities, they also have their differences.
The standard deviation calculations in my experiment are used for finding out how the common wheat sample values are spread above and below the mean. A high standard deviation indicates that the data is widely spread around the mean, which makes the data less reliable. A low standard deviation in the other hand indicates that the data points are located closely to the mean, which makes the data very reliable. The standard deviation provides important information of the data’s reliability and its significance when making the conclusion. The calculated standard deviation value for all samples with different sucrose concentrations in Table 1.3, Table 1.5 and Table 1.7 is between 2.63 and 4.02.
The second experiment demonstrated that when cheese is placed in the same environment, it would lose moisture until it reaches equilibrium. The moisture lose is due to the cheeses high water activity. The cheese would become leathery and unspreadable as moisture is lost. The third experiment examines equal amounts of cheese and crackers being placed in an isolated environment.
The process itself begins with vapor diffusion, a way to grow
