tonicity on cell membrane lab report Essay

Blood is a non-Newtonian fluid that contains many components. One such component is red blood cells. Due to the red blood cells having the tendency to clump together at low velocities, calcium chloride was added in order to cause a thrombus formation. The blood used in this experiment was sheep’s blood.

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.

**1.1 – Diagram & Description of Cellular Components will be found in handwritten portion of assignment**

Blood is a non-newtonian fluid that contains many components. One such component is red blood cells. Due to the red blood cells having the tendency to clump together at low velocities, calcium chloride was added in order to cause a thrombus formation. The blood used in their experiment was sheep’s blood.

Every eukaryotic and prokaryotic cell has a selectively permeable membrane, also known as a cell membrane. Its function is to help protect the cell and filter what can flow in and out of it. Some

The purpose of this lab being performed is for one to determine the normal osmolarity of our fluids, and how the different concentration solutes has an impact on the red blood cells shape. Depending on the solution being used the cell can either, swell up, crenate, burst, or keep its shape. Depending on the osmolarity of a cells interstitial fluid, the cell might change its tonicity if osmosis occurs. Osmolarity is the concentration of ions in a one-liter solution. We will be able to determine what solutions causes change in shape and tonicity by the different types of solutions we have by changing the extracellular fluid concentration of the solutes in the red blood cells. We will place the red blood cells in a 5% hypertonic solution, hypotonic

The water concentration inside the cell is higher so the direction of osmosis will be away from the cell and water leaves the cell.

Osmosis and diffusion are processes by which water and solute particles, respectively, pass through a selectively permeable membrane. When water moves across a cell membrane the processes of osmosis and diffusion take place to maintain a balance between the water and solute particles inside and outside of the cell by moving from a region of high concentration to a region of lower concentration. If the concentration of solute particles inside and outside the cell are equal then the solution outside the cell is referred to as isotonic, but if the concentration of solute particles outside the cell are greater or less than the concentration inside the cell then the solution is referred to as hypertonic (greater) and hypotonic (less). A hypertonic solution results in shrinkage of the cell as water leaves the cell via osmosis to compensate, while a hypotonic solution results in swelling of the cell as water enters the cell via osmosis.

The purpose of this lab was to understand the effect of molecular size and polarity on the ability of certain molecules to pass through the membrane of red blood cells. The lab involved a series of propanol test solutions containing 4 mL of 0.3M propanol, propanediol, or propanetriol, and 12 mL of bovine blood. The test tube was held up in front of a slit lamp to measure the hemolysis time of the bovine blood. The slit lamp consisted of a light source positioned behind a piece of cardboard with a hole in which a thread was suspended. The light from the lamp illuminates the culture tube, allowing the thread to be seen once hemolysis occurs. The results are shown in Figure 1.

When erythrocytes are placed in a hypotonic solution (a solution with lower concentration than the cell), water moves into the red blood cell, causing it to swell, to increase its volume and eventually burst ( haemolysis). When erythrocytes are

The general concept of this lab was to see the contractions of Tetrahymena in different solute concentrations. This was to demonstrate a cell's ability to follow through osmosis and try to reach equilibrium. The result of this lab shows that when tetrahymena is placed in distilled water its vacuole contracts at a faster pace or more rapidly. This is a result of the fact that there is zero solute concentration so therefore it will become hypotonic, causing the cells to grow rapidly and release water just as fast. The cells all had less contractions as the solute concentration went up because the cell will be hypertonic and essentially shrink and take slower to expand. This lab relates to osmoregulation because our cells try to get to an equal

Tonicity is used to determine which of the three types each fluid would fall under and is essentially the change that occurs to the cell size because of the amount of water pushed into or pulled out of the cell by each type of fluid. Isotonic fluids, such as 0.9% saline, whole blood, packed RBC’s, and lactated ringers, neither swell or shrink a cell because their osmolality or pressure equals ICF. Hypotonic solutions, such as 0.25% saline, D5/0.25% saline, and 0.45% saline, cause the cells to swell because the osmolality is lower in the hypotonic solution than ICF meaning there is a less dense concentration of particle within the solution so the water molecules move to the particles within the cell. Hypertonic solutions, such as D5/0.9% saline, D5/0.45% saline, D5/lactated ringers and 3% saline, cause the cell to shrink because they have a higher osmolality than ICF which means they pull the water out of the cell due to the dense particle concentration of the solution. D5W solutions are unique in that they are isotonic when they are outside the body but become hypotonic when they are introduced into the body. Within these compositions there are two more solutions types known as crystalloid and colloid. Crystalloid solutions “typically have a balanced electrolyte composition and expand total extracellular fluid volume (Shields, 2015), some examples are 0.9% saline and lactated ringers. Colloid solutions exert osmotic pressure which pulls water into the ECF to help expand volume, some examples of this are albumin and

We drew three different pictures; each picture represented one of the terms. The hypotonic blood cell looked like a faint circle because we drew it after it had already ruptured. Once a cell ruptures, it is then called a “ghost cell” because it does not really exist anymore; therefore, we just pretend there is a very light cell floating around to understand the concept. The hypertonic blood cell looked like a tiny, pointy bush. This is because the cell was shriveled up and was like a paint splotch. The isotonic blood cell looked like a regular circular cell. This is because when something is isotonic, it has reached equilibrium and is equal on the outside and the inside (chemically), so its structure is not

Test results concerning the permeability of cell membranes found that temperature stress effected the function of cell membranes. The test exhibited that cell membrane function is altered at temperature extremes relative to room temperature or 23°C. The test results found that the further the temperature was from room temperature the higher the betacyanin concentration was in the water meaning that the betacyanin escaped the cell membrane indicating a change in its functionality from the control; the control being the test done at room temperature (23°C) and resulting in an average colorimeter reading of 0.0098 units of optical density (see figure 1). All other temperatures resulted in a higher average reading for absorbance of betacyanin, meaning that more betacyanin was released from the cells.

In this lab we are going to discovery how osmosis works using a semi-impermeable membrane a potato slice. Osmosis is known as the movement of water in and out of a cell. To understand how this works we must understand two terms. Hypotonic means the environment has less solutes compared to the inside of the cell. Hypertonic means that the environment has more solutes compared to the inside of the cell. With osmosis water will always move from hypotonic too hypertonic. So the question is will water move into the potato or out of the potato? Will these results change when placed in different morality of salt water? To calculate these results, we will measure the mass of potatoes cut into equal sizes then soak these potato slices in different morality of NaCl for thirty minutes and measure the mass change in each potato slice.