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Infusorian Feeding Cycle
 

This virtual laboratory will help you study the digestive processes that take place inside of an infusorian organism. Everything you need to know is right in front of you on the virtual worktable.

Pour a couple of drops of infusoria-containing solution on to the glass slide using a pipette. Add two drops of congo red yeast. In order to slow down the movement of the infusorians, add a drop of methylcellulose, and add a bit of cotton wool into the solution. Cover the observation material with cover glass, and study it under the microscope.

The microscope is shown on the right side of the model, and the focusing knobs for magnification of the image are shown there as well. Use your mouse to magnify or minimize the size of the image of the infusorian. You can also see those parts of the image that did not fit in the objective by dragging the picture with your mouse. Press "Back" button to return to the worktable.

If you set up the preparation correctly, you will see one or two infusorians under the microscope. The filaments of cotton wool are constricting the freedom of movement of the infusorian, preventing it from venturing beyond the sides of the screen. Little balls that are swimming in your line of sight are the yeast cells. Modify the image in such a way so that one of the infusorians would be in the center of the screen, and magnify it. You can see that the infusorian is consuming the yeast cell through its oral cavity. Inside of the infusorian, the food goes into the digestive vacuole and is digested inside it, moving through the cell. A change in color of the digestive vacuole signifies a change in its pH. Digestive ferments are most active at pH of 5.7-5.8 (red-orange color.) The leftovers of the food that cannot be digested are excreted.

Modify the settings of the experiment, changing the amount of components used for the final solution. You can clean off the pipette in a special trash bin. If you have included something that you did not mean to have on the glass, lift the glass with your mouse, and it will come clean. To return the worktable to its initial state, press "Reset".

 
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