Rubber Egg Lab Essay examples

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.

B. The nature of plasma membrane. If the membrane is composed of lipid portion., only lipid soluble molecules can pass through while water molecules cannot.

The purpose of these experiments is to examine the driving force behind the movement of substances across a selective or semiperpeable plasma membrane. Experiment simulations examine substances that move passively through a semipermeable membrane, and those that require active transport. Those that move passively through the membrane will do so in these simulations by facilitated diffusion and filtration. The plasma membrane’s structure is composed in such a way that it can discriminate as to which substances can pass into the cell. This enables nutrients to enter the cell, while keeping unwanted substances out. Active

1. Understand the importance of diffusion to cellular metabolism and the how it constraints the evolution of cell/body size and shape

13. Understand the transportation of potassium and sodium across plasma membranes. (p. 10 bottom right, p. 20 bottom right, p. 21 diagram)

1. What two parameters are responsible for creating the movement (filtration and reabsorption) of fluid across the capillary wall?

The concentration of dissolved substances is less in the extracellular fluid than in the cytoplasm. Hypotonic Solution Concentration of dissolved substances (solute) Concentration of water (solvent) What happens to an animal cells? Inside the cell Greater Less Outside the cell Less Greater Membrane

In this experiment the process of osmosis is being observed and the different conditions in which osmosis occurs. In the egg osmosis experiment kinetic energy is used making this process a passive transport ‘in passive processes concentration or pressure differences drive the movement (Marieb,Smith, 2007)’ since ATP is not required which is called facilitated diffusion.

Exercise 1: Cell Transport Mechanisms and Permeability: Activity 3: Simulating Osmotic Pressure Lab Report Pre-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1. Which of the following is true of osmosis? You correctly answered: c. It is a type of diffusion. 2. Which of the following occurs when a hypertonic solution is added to cells? You correctly answered: d. The cells shrink. 3. The variable that affects osmotic pressure is You correctly answered: a. the concentration of nondiffusing solutes. 4. The net movement of water would be into the cell in a You correctly answered: b. hypotonic solution.

Introduction: Cell membranes contain many different types of molecules which have different roles in the overall structure of the membrane. Phospholipids form a bilayer, which is the basic structure of the membrane. Their non-polar tails form a barrier to most water soluble substances. Membrane proteins serves as channels for transport of metabolites, some act as enzymes or carriers, while some are receptors. Lastly carbohydrate molecules of the membrane are relatively short-chain polysaccharides, which has multiple functions, for example, cell-cell recognition and acting as receptor sites for chemical signals.

6. Ringer’s solution would be isotonic solution. IV is used when a patient loses blood. this Solution would be given so that the concentration gradient gets same inside and outside of the body and so that there could not be any net change in the cell shape. (Nicole, 2012).

3. Evaluate the lab and data collected. would you conclude that the lab represented active transport or passive transport? explain your answer

Diffusion is the transfer of molecules from an area that has a higher concentration to an area that has a lower concentration. Osmosis is the diffusion of water. The purpose of this experiment was to study the process of osmosis. In order to test osmosis, eggs that had been soaking in vinegar were taken and placed in four beakers of solution with different levels of glucose. Using this experiment we were able to determine the rate of osmosis of different solutions, with various amounts of glucose, through eggs. In the results of this lab it was found that the eggs were either hypertonic or hypotonic and that the

There are many different types of transport within a cell that can end up being very complex. On the outside of the cell is the plasma membrane that protects it from the outside environment. The plasma membrane is very picky about what it allows through it. It wants to let in oxygen and nutrients, but keep out harmful bacteria. It also wants to keep in the proteins and nutrients that are already in the membrane. Because of this property, the plasma membrane is called a selectively permeable membrane and it has two basic transport processes. In passive transport processes it is the concentration differences that drives the movement. The two passive transports are diffusion and filtration. In active transport processes the cell provides energy in the form of Adenosine Triphosphate (ATP) to power the process. The two active transport processes are primary which is driven directly by ATP or secondary which is driven indirectly by ATP (Marieb P61). For the most part, molecules will diffuse passively through the plasma membrane if they are small enough, but they must be aided by a concentration gradient. A concentration gradient is when there is a difference in concentration of a substance from one area to another (Amerman P75). This property of the plasma membrane is critical to the cell. Without this property the cell would not be able to exchange the oxygen and nutrients it needs to with the extracellular fluid (the fluid located in the spaces between the cells). The

There are two different types of processes that are used to allow substances to get through the plasma membrane. The first type is passive process which is the differences in concentration/pressure inside and outside of the cell. The two parts of passive processes are diffusion and filtration. Diffusion also has two different types, simple and facilitated. This is easy to remember because simple