Cell Transport Mechanisms

CELL TRANSPORT MECHANISMS

And PERMEABILITY

COMPUTER SIMULATION

Lab # 5 Using PhysioEX

Introduction

The purpose of this experiment was to see which way substances will move either inside the cell or outside the cell given different situations for solute, water, kinetic energy and ATP. The plasma membrane allows it to be selective on what it passes into the cell and out of the cell. However, in order to simulate facilitated diffusion, simple diffusion, osmosis, filtration and active transport one must use a semipermeable membrane to depict the cell membrane. One of the experiments portrayed how molecules move from an area of higher concentration to lower concentration, this is called simple diffusion. An example of diffusion on the human body would be the diffusion of oxygen and carbon dioxide in and out of the lungs. The second experiment involved facilitated diffusion which is moving glucose either along or down its concentration gradient. An example in the human body would be the small intestines where glucose passes across the cell membranes using a transport protein. The third experiment was osmotic pressure where it moves water down its concentration gradient toward the solute with the highest concentration. An example in the human body would by the kidneys where water and salt pass back and forth until the salt solute is equalize. Despite all the experiments the last one was most interesting which involve active transport which is the most important process in the human body. It allows molecules to move against its concentration gradient therefore allowing necessary proteins and nutrients to supply our demanding needs in the human body.

Experiment

Materials for All Activities:

The materials used in the experiment were the Human Anatomy and Physiology Laboratory Manual, the physio-EX Version 8 CD-ROM and my home computer.

Methods

Activity 1 - Simple Diffusion

Hypothesis

In this experiment I hypothesize that the Albumin will have the bigger molecule weight and NaCL, Urea and Glucose will not pass through the membrane and that NaCL will not diffuse at a higher rate.

Method

The methods throughout this experiment utilized the physio – EX version 8 CD - ROM which allowed me to simulate simple diffusion without using real materials. Although the experiment utilizes simulation and compressed time all results would be the same if using real materials in a laboratory setting. The first step was to take the 20 MWCO membrane and drag it to