Life Story of the Paramecium

foreign dozens of different living things but there are many other creatures we don't usually see because the world of these creatures is so tiny it can fit into a small jar a drop of pond water magnified hundreds of times by a microscope reveals a bustling collection of these tiny creatures each made up of only one cell [Music] some contain chlorophyll and use water nutrients and sunlight to manufacture their food [Music] others are animal-like and browse or hunt to find food and one type the euglena can do both it has chlorophyll and so can photosynthesize but if there's not enough light it searches for a meal by hunting many one-celled organisms are very active and different types have developed different ways to move this is perinema it pulls itself forward by this hair-like extension that bends and flutters just at the tip EBA flows Along by the fluid motion of its membrane while vorticellas are attached to Long stalks that act as loaded Springs when they're Disturbed they pull back in an instant [Music] the paramecium moves by beating tiny hair-like structures called cilia there are more than 25 000 cilia covering the paramecium cell body they beat in unison like oars on a rowboat and working together pushed the cell through the water in a twisting spiral motion to get an understanding of the small size of these organisms a human hair is placed next to a paramecium notice how the paramecium moves if something is in its way it bumps it backs up and starts again this complex motion is performed by coordinating the movement of its thousands of cilia organisms such as the paramecium may be more complicated than you realize like your body this single cell performs all the functions necessary for life including complex behaviors the tiny moving specks in this test tube are a large population of paramecium strong direct sunlight is harmful to these cells while the bottom of the tube is covered with dark paper the tube is exposed to sunlight what do you think will happen when the cover is removed we find most of the paramecium have gathered in the bottom half of the tube they reacted to the sunlight by moving away to the Shaded protection below to find how the paramecium eat red dye is added to their food as the paramecium moves its cilia create invisible whirlpools that pull the dyed food into its mouth [Music] inside the food collects in bubble-like cavities called vacuoles easily distinguished by the red dye currents in the liquid of the cell move the vacuole slowly about and the food is digested as it circulates using a device called an electron microscope we can look inside the food vacuoles and see what the paramecium has eaten its last meal like its first was bacteria cells neatly packed and ready for digestion an organism must expel the waste a paramecium does this by pushing waste particles out a slit in the side of the cell [Music] in addition to food the paramecium ingests a great deal of water when it eats this extra water is collected in special structures called contractile vacuoles [Music] when a vacuole is full the water is squeezed through a pore and out of the cell like all living things paramecium must breathe oxygen slowly passes in at the surface of the cell while carbon dioxide passes out [Music] also like all living things paramecium reproduce they do so by simply dividing into two parts each of the two new daughter cells is an exact copy of the original cell only half as big with unlimited food and no natural enemies paramecium and other single cell organisms would continue to reproduce Two by Two and in only a hundred days the mass of their numbers would nearly equal that of the Earth itself [Music] organisms have evolved into thousands of different species each unique [Music] foreign [Music] [Music] [Music] [Music] a few types form colonies like this volvox in this species groups of cells are specialized to perform only certain life functions you can see how studying these simple cell colonies can provide a better understanding of more complicated organisms such as plants and animals because whether an organism is one cell or many the fundamental functions of Life are always the same foreign