Amphipathic molecules- hydrophobic & hydrophillic regions
Fluid mosaic model- states that a membrane is a fluid structure with a mosaic of various proteins embedded in
7. Membrane proteins are the mosaic part of the model. Describe each of the two…
This model of the membrane is called the fluid mosaic model, proposed by Jonathon Singer and Garth Nicholson in 1972. It shows the way that membranes allow materials to move across…
Hypothesis statement: If you put sugar water in one cup, salt water in another cup and plain water in another cup then the slice of potato will expand in the sugar water shrink in the saltwater, and stay the same in the regular water because of the hypertonic, hypotonic and isotonic solution.…
In the fluid mosaic model, protein and lipid components move rapidly in the plane of the membrane. Membrane proteins are dispersed and individually inserted into the phospholipid bilayer, with only their hydrophilic regions protruding far enough from the bilayer to be exposed to water. This maximizes contact of hydrophilic regions of proteins and phospholipid with water while providing hydrophobic parts…
13. What is the fluid mosaic model? What is the function of each component of the model? What determines the flexibility of the cell membrane?…
The aim of this experiment was to test the effect of surface area on osmosis and the effect of solute concentration on osmosis. To test this aim to hypotheses were devised. 1) If potato pieces are immersed in various salt solutions, then the pieces with the greatest surface area to volume ratio will experience the greatest weight change, because more water can move by osmosis across the potato cell’s semi permeable membrane. 2) If potato pieces are immersed in various salt solutions, then the pieces immersed in the most concentrated solution will experience he greatest weight change, because more water must pass across the potato cells semi permeable membrane by osmosis to achieve an equilibrium. The results from testing these hypotheses did not support either and were shown to be flawed because they did not reflect the theories of osmosis relating to surface area to volume ration and salt concentration.…
The purpose of this experiment is to observe the osmosis reaction in a potato with salt and water. In cooking cooks will soak their cut potato's in water if they will not use them immediately. This allows the potato's to be used later without turning color. The experiment shows the flow of water through the membranes of the potato with salt over a period of four hours.…
The cell surface membrane which surrounds all cells consists of many components, which together is referred to the fluid mosaic model. It is called fluid because the individual phospholipids can move relative to one another, making the membrane flexible so it can constantly change shapes. It is called mosaic as the different types of proteins are embed in the membrane in different shapes, sizes and patterns, so it resembles a mosaic.…
7. Which of the following best describes current understanding of the fluid mosaic model of membrane structure?…
The way to get the full results of this lab was through the process of osmosis. Osmosis is the movement of water across a membrane into a more concentrated solution to reach an equilibrium. When regarding cells osmosis has three different terms that are used to describe their concentration. The first of these words is isotonic. Cells in an isotonic solution show that the water has no net movement and the amount of water that goes in is the same that goes out. Isotonic comes from the root iso, which means equal. This makes sense because the definition of isotonic is: same concentration. The second out of three words is hypotonic. Cells in a hypotonic solution make the water move into the cell to spread out the cells solutes to eventually reach an equillibrium. Hypotonic comes from the root word hypo, which means low/below. The actual definition for hypotonic is: less concentrated. Hypertonic is the last out of the three words. A cell in a hypertonic solution makes the water leave the cell to try to spread out the solutes outside to eventually reach an equillibrium. Hypertonic comes from the root word hyper, which means more/high. The definition of hypertonic is: more concentrated.…
Aim To observe and measure the effect of osmosis on the mass of potato using a starch solution. Introduction In order to measure the effect of osmosis, eighteen pieces of potato were cut and placed in six groups, each group of three pieces cut to weigh as close as possible to one another. For each potato group, a test tube was half filled with a starch solution varying in concentration from 0% (water) to 1%. Hypothesis…
Introduction: Osmosis is the diffusion of water from a higher concentration to a lower one through a semi-permeable membrane and occurs in the cells of organisms. It is affected by the addition of solute which would lower the water potential, making water potential and solute concentration inversely related. The concept of osmosis loosely described is that the presence of more solute outside the cell means the presence of less solvent (or water molecules in this case) and vice versa; the goal of osmosis is for the water molecules inside and outside of the cell to be equal, causing equilibrium and a stop to net water movement. The goal for a recent lab was to test whether cubes of potato would gain or lose weight depending on the amount of molar concentration of sucrose they soaked in. Solutions made of different molar concentrations of the solute sucrose were prepared before this lab. Potato cubes were weighed and recorded as the initial mass in the data. Four cubes of potato were placed into 100 mL of each solution and let stand overnight. The cubes were then taken out for the final total mass to be measured and recorded. In this experiment, the potato cubes were the dependent variables, and the molar concentrations were the independent or manipulated variables.…
The purpose of this lab was to observe the rate of osmosis and diffusion, as well as the effect of molecular size of the particles on this rate. Part I of the lab was a demonstration of osmosis and diffusion, that dealt with raisins in different liquid environments, each with a different concentration of sugar. Part IV of the lab was using the same idea as the demonstration, by putting objects in different concentrations of a substance; in this case elodea leaves in salt water. In both cases, the objects in a greater concentration of the substance were stripped of their water. However, where there was a little or no concentration of sugar or salt, the objects did not lose their water, and in the case of the raisin, became saturated with excess…
Do you need something explosive as a treat or snack for a 4th of July party? A tasty snack that does not have a lot of harmful ingredients is licorice. This means you have a simple way to make something for a fun snack like dynamite party favors.…
The purpose of the lab is to see how different size potatoes have faster water movement depending on the concentration of sucrose it was placed in. We had two sized potatoes, 6g and 10g, and placed each in three different dilutions of sucrose at 0.5M, 0.1M, and 0.05M. We also placed a 6g and 10g potato piece in water to act as a control. Based on the weight percent change over 60 minutes, the 6g potato piece had faster water movement than the 10g. This confirms out hypothesis that smaller potato pieces will have a faster rate of water movement.…