The Concentration Of Water Molecules

Cells and molecules in the environment are constantly moving and changing, for cells to function properly there is a need for equilibrium to be met. The size of the cell and the solution outside of the cell affects the rate of diffusion and osmosis in the cell. Cells are constantly trying to reach an equilibrium with the molecules and substances around it, which is why there are such terms as: hypertonic, hypotonic and isotonic. The procedures allowed testing of whether or not surface area or volume increased diffusion and how different substance control diffusion. Cells are constantly moving to reach equilibrium through diffusion and osmosis.

Explain what happened to the blood cells at the various levels of concentration. Be sure to refer to the solutions as being hypotonic, hypertonic and isotonic.

In this lab experiment, half our group observed and measured osmosis using dialysis tubes that were represented as the semipermeable membrane. It is permeable to water and other small molecules but is impermeable to larger molecules such as the sucrose solution used in each of the four beakers and tubing. The other half of our group observed the tonicity of sheep blood to determine whether the blood was isotonic, hypotonic, or hypertonic. The 85 g/dL of NaCl solution was the ideal isotonic number in relation to the sheep blood cells as well as a reference to the other observations of the solutions.

The higher the water potential in one location compared to another location, will cause the water and molecules to move from the high potential to the low water potential.

The difference is that along with large molecules, living cells prevent molecules with positive charges and solubility. This is not representing in dialysis tubing, and is only found in living cells because the tubing is only based on molecular size (98). When referring the rate of diffusion, the concentration gradient influences the diffusion rate, based on the factors of temperature. The ability for molecules diffuse from high to low concentrations primarily depends on the concentration gradient between the two areas.(96-99). My hypothesis for the study is that in the hypotonic, hypertonic, and isotonic solutions, the direction and rate of osmosis will determine based on the concentration inside the dialysis tubing. My prediction is that if the solution is hypotonic the results will decrease, if the solution is hypertonic the results will increase and if the solution is isotonic the solution will vary and or remain constant.

In a cell, diffusion occurs across a selective permeable membrane of the cell that allows the cell to regulate and control the passage of substances. As well as controlling what passes through the membrane, the selective permeability also controls how quickly those allowed substances are able to pass through the cell membrane. When a cell is placed in a hypotonic solution, the substance wants to quickly diffuse through the cellular membrane in attempt to balance the concentration. Due to this, too much of the substance enters the cell causing the cell to swell and rupture, otherwise known as hemolysis. The purpose of this lab is to test if and how the factor of polarity of a molecule affects the diffusion rate of those molecules through a permeable red blood cell membrane in a sample of ovine blood. Testing this factor and its effect on diffusion rate is important in the biological world as it helps understand how our body regulates our own substances and molecules within us, but also how our body will react and respond to other substances such as medicines. It is hypothesized that this factor of polarity will determine how quickly or slowly molecules will diffuse across the cell membrane. Smaller molecules that have relatively low polarity will be able to cross the membrane more easily and at a faster rate than those molecules that

The major objective of the experiment was to test the effect of the concentration gradient on the diffusion rate. It was hypothesized that the greater the stronger the concentration gradient, the faster the rate of diffusion would be. To test this, dialysis tubes were submerged in different concentration fructose solutions. We weighed the tubes at specific time intervals to measure the rate of diffusion of water in each different solution. The results illustrated that increased concentration gradient increases the rate of diffusion of water in the tubes. We concluded that as concentration of the

The experiment groups are slide #2, #3, and #4 were compared to the control group. The red blood cells on slide #2 have similar appearance to the slide # 1. This implies that 0.9%NaCl is isotonic to the red blood cells. There was no net gain or loss of water because the cells concentration of solute is equal to the 0.9% NaCl solution. The red blood cells on slide #3 showed a decrease in size and more space between the cells was observed. This implies that 10% NaCl is hypertonic to the red cells. There was a net loss of water because the solute concentration of cells is lower than that of the 10% NaCl. Red blood cells on slide # 4 were not visible. This implies that Distilled water (dH2O) is hypotonic to the red cells. There was a net gain of water because the solute concentration of the cells is higher than of the (dH2O) solution. This means the distilled water is hypotonic to blood and that the water moved into the RBCs and they

Diffusion is the movement of molecules from a region of higher concentration to a region of lower concentration. The rate at which molecules diffuse can be determined by the relationship of molecular weight and that rate of diffusion through a membrane. Hypothesis of this experiment is that the fluid with higher molecular weight will diffuse at a slower rate and distance.

Review Sheet Results 1. Explain the effect that increasing the Na+ Cl- concentration had on osmotic pressure and why it has this effect. How well did the results compare with your prediction? Your answer: The increase of the Na+Cl- concentration increased osmotic pressure the Na+ Cl- molecules diffused through the 50 mwco membranes and didn't go through the 20 mwco membranes. the more Na+Cl- we added to the 20 mwco membrane, the more the osmotic pressure went up. When I looked at my results I noticed when Na+Cl- was added to the 50 mwco membrane, there was no increase in osmotic pressure. This is becasue the Sodium chloride couldn't diffuse through the 50 mwco membranes. The higher concentration of molecues on one side of the mwco membrane forces the water movement to move to the side of greater solute concentration. 2. Describe one way in which osmosis is similar to simple diffusion and one way in which it is different. Your answer: Osmosis is similar to simple diffusion because both of these precesses have the passive transport characteristic. This is where particles in a solution move from an area of high solute concentration to an are of low solute concentration. Also neither of these processes need energy from an outside source to function. Osmosis is different than simple diffusion because in osmosis, if we have a selectively permeable membrane, this membrane is

Water is essential for life as we know it on earth. It is used by plants

Water is essential for life on earth. Water is needed for growing food, keeping ourselves clean, generating power, controlling fire and most importantly to stay alive! This list is simply non-ending. This shows that water is an integral part of our daily life and we are heavily dependent on it.

Diffusion is an automated process by where the levels of oxygen, water and carbon dioxide pass over a ‘semi-permeable membrane’ between the walls of the cells and blood vessels to create a level environment. This membrane only allows these three elements to pass whilst retaining other elements such as blood cells, hence semi-permeable. The high concentration on one side of the cells transfers through this membrane until the level is equal on both sides.

Water a transparent and formless liquid that is one of the most important things that we have on planet Earth. Every living thing needs water to live, so it is considered to be the source of life, by many.

The movement of water molecules across a semi-permeable membrane is the process of osmosis. If there is a solute and a solvent, each containing different concentration levels, then the water would move along its concentration gradient until each side of the membrane are equal. The water moves because the membrane is impermeable to the solute and the solute concentrations may differ on either side of the membrane. Water molecules may move in and out of the cell, but there is no net diffusion of water. Water will move in one direction or the other, and this is determined by the solute or solvents concentration levels. If the two solutions are of equal concentrations, they will be isotonic. If the concentrations are unequal, the