Скачать или смотреть Feeding Paramecium with stained yeast

Paramecium caudatum is a well known ciliate and model organism in biology . Its comparatively large size make it easy to observe its internal features. This video shows the digestion process in Paramecium using bakers yeast that was stained with congo red - a pH indicator.

A small amount of fresh yeast is dissolved in water and the solution is brought to a boil to disrupt the cell wall of the yeast. When the solution has cooled down, a few drops of a 0.1% congo red solution is added to the yeast. The yeast take up the dye and a small drop can be added to our ciliates which will readily phagocytose the yeast. During the digestion process, the food vacuole is acidified by proton pumps which activates the digestive enzymes. Due to the acidification process, the yeast stained with congo red turn blue.

Microscope:
Olympus Vanox AHBT3 with DIC

Objectives used:
Olympus SPlanApo 20/0.7
Leitz NPL Fluotar 50/1.0 Oil


The camera is a Panasonic S1 adapted with an Olympus NFK 2.5x eyepiece.

Music:
Fern - Ann annie