Analyzing The Primary Features Of Eukaryotic Cells

The experiment is done to visualize tonicity and osmoregulation in a mock animal cell for comprehension of the concept. A grape will be used for the representation and exposed to three different tonicities. The changes or lack thereof in weight can show the movement of water to balance its tonicity through osmoregulation. The predicted results with the green grapes in solution after four days of research will be reflective of how a hypotonic, hypertonic, and isotonic cell will react. The hypotonic solution will cause the grape to shrivel noticeably and be slightly browned, leaving it with less weight. The hypertonic solution will cause the grape to have the outer skin torn, starting from the where the stem attached, the grape should be expanded as well. The weight will increase. The isotonic solution will have little change, still plump and the same weight.

This exercise is aimed at giving a better understanding of the process of osmosis by analyzing how the decalcified eggs behave under different experimental conditions. The shell-less eggs used represented a model for a living cell and its selectively (semi) permeable membrane.

Osmosis is described in one of three ways when comparing more than one solution. The cell’s external and internal environment helps determine tonicity, which is defined as how the cell reacts to its environment. When the cell’s environment is equal in osmolarity to itself and there is no change, it is considered an isotonic solution. When the environment has a higher osmolarity, shrinkage occurs and it is considered a hypertonic solution. When the environment has a lower osmolarity, swellings occurs and it is considered hypotonic.

Purpose: The purpose of this lab is to familiarize you with osmosis and, specifically, what happens to cells when they are exposed to solutions of differing tonicities.

When I looked at the cells with a drop of distilled water, I saw a rigid cell wall that surrounded each cell. I also saw a cell membrane that lined the cell and green chloroplasts that lined each membrane. The whole cell had a green hue and the chloroplasts were a brilliant green. I saw tiny cells with green circles moving inside of them under the 100 times magnification. However, in the 400 times power, I could see the separation between the cell wall and the cell membrane more than in the 100 times magnification. The cell’s volume did not surpass the cell wall. When I added a drop of salt water to the leaf, the cell wall remained in place, whereas the cell membrane shrunk and did not line the cell wall as it was with the distilled water. The chloroplasts moved with the cell membrane and were closer to the each other. The chloroplasts were compressed together when the cell was exposed to salt, whereas in the distilled solution, the chloroplasts were able to move freely. When the plasmolyzed cells were under the 100 times magnification, I could see the shrinkage of

This experiment will use Elodea plant cells as the research object. Three different tests will be performed to examine how Elodea plant cell would respond in solutions with different osmolarity, and to find out which

The lab for this paper was conducted for the topic of osmosis, the movement of water from high to low concentration. Five artificial cells were created, each being filled with different concentrated solutions of sucrose. These artificial cells were placed in hypertonic, hypotonic, or isotonic solutions for a period of 90 min. Over time, the rate of osmosis was measured by calculating the weight of each artificial cell on given intervals (every 10 minutes). The resulting weights were recorded and the data was graphed. We then could draw conclusions on the lab.

“Eukaryotic cells are complex and include all animal and plant cells. Prokaryotic cells are smaller and simpler, e.g. Bacteria” - (AQA 2008)

Many molecules and hydrocarbons diffuse down the concentration gradient, moving from a high concentration to a low concentration. Without diffusion, osmosis cannot occur, osmosis is diffusion of water. During osmosis in animal and plant cells, tonicity, ability to cause a cell to gain or lose water, causes three different solutions, isotonic, hypertonic, and hypotonic. The purpose of the experiment

Van’t Hoff’s Law suggests that the osmotic potential of a cell is proportional to the concentration of solute particles in a solution. The purpose of this experiment was to determine if there are any differences between the osmolalities, the no-weight-changes of osmolalities, and the water potentials of potato cores in different solutions of different solutes. The percent weight change of the potato cores was calculated through a “change in weight” method. The potato core’s weight was measured before and after they were put into different concentrations of a solute for 1.5 hours. In our experiment, there were no significant differences from the osmotic potentials of our results and the osmotic potentials of other scientists work. Ending with chi square values of 2.17 and 2.71, and p values of 0.256 and 0.337, concluding that there is no difference in water potentials of potato cores in different solutions of different solutes at varying concentrations.

This lab's function was the study of osmosis and concentration gradients. Osmosis is the movement of water from an area of high water concentration to a lower water concentration through a selectively permeable membrane. Permeable membranes allow certain solvents to pass through while selectively preventing solutes from doing the same. Tonicity dictates the direction and speed of diffusion. Plant cell thrive better in an hypotonic environment, allowing them to always be full of water and thus turgid.

After conducting the experiment, the hypothesis “if a cell experiences osmosis, then it will shrink, or enlarge depending on the type of solution,” is proven incorrect. In both the distilled water and 1% salt solution, water from the potato cores’ surroundings moved into the cores causing them to gain mass. The cores gained water mass due to the fact that they were hypertonic while their surroundings were hypotonic. On the other hand, in the 3% salt solution and the 5% salt solution water from the potato cores moved out to their surroundings. The cores lost water mass because they were hypotonic while their surroundings were hypertonic.

All eukaryotic cells have microtubules, which are hollow rods assembled from a globular protein called tubulin. Microtubules grow in length by adding tubulin dimers. Those dimers can also be disassembled, which would allow the tubulin to build microtubules elsewhere in the cell. The two opposite ends of of a microtubule are actually pretty unique. One end can can accumulate or release tubulin dimers at a much higher rate which allows it to grow or shrink during cellular activities (Campbell, pg.114). The microtubules and the motor proteins of a cell are closely related, which is why I must introduce some of there functions. Cell motility generally requires interaction if the cytoskeleton with motor proteins. They work together with plasma

Eukaryotes DNA is divided between a set of different chromosomes, in particular the human genome is distributed over 24 different chromosomes in the nucleus. Each chromosome consists of a single, long linear DNA molecule associated with proteins that wrap up the DNA into a more compact structure: the chromatin, which derives from the Greek "chroma" meaning "color", for its staining properties.

Both the membrane and the solute concentration are factors in how a cell operates in a solution. The tonicity will then depend on how that concentration is able to flow across the membrane. We discovered that cells without a cell wall typically fare best in an isotonic environment, where the water will stay at the same rate in both directions, keeping everything stable. Plant cells, or any others with a cell wall, use the cell wall to expand a bit further by applying a back pressure called turgor pressure to oppose any further water uptake. This allows the cell to get fat and happy in a turgid state, which most plant cells find to be the healthiest for them.