Living Things In A Drop Of Water (1985)

[Music] the eye is a marvelous instrument a window through which we explore the world but there is a great deal that the eye cannot see we have invented instruments which Aid our eyes as we explore the world around us powerful telescopes and cameras can see into the far reaches of space revealing the wonders of the universe microscopes coupled to cameras allow our eyes to see and record Another Universe the realm of the very small a universe of very tiny living things photography permits us to speed up or slow down the world around us so events which may take hours seem to happen in just a few seconds and events which happen too fast for us to see with our eyes can be slowed down by slowing down or speeding up everyday events we can learn how they take place we can better understand the world in which we live even with its limitations the eye reveals much about our world we can see many different life forms in the animal world alone a great variety of creatures of many sizes and shapes rhinoceros huge lumbering Beasts of the African grasslands ducks not very large at all but found almost everywhere on Earth zebras with their uniquely striped patterns of hair elephants the largest animals found on land giraffes the tallest and among the most graceful creatures on our planet whales the mysterious Giants of the Earth oceans share their home with small organisms Plankton one of the most important parts of the food chain in water both fresh and salt we can discover a remarkable Universe of living things on a journey of exploration in a freshwater Pond we can find a variety of life forms from freshwater plants to fish but what else is there let's take a closer look at a sample of pond water using a magnifying glass to help our eyes we can see thousands of tiny specks they are called protests one- celled organisms here we compare the protests the white specks in the water to the size of the eye of a needle this journey of exploration begins with the aid of a microscope a slide has been placed under the microscope containing a drop of water alive with protests a needle is placed on the slide you can see that even the largest protests move easily through the eye of the needle to us this is a very tiny space to a protest it is vast protests are so small that a single small drop of water may contain thousands yet these incredible small organisms much smaller than the eye of a needle and consisting of only a single cell perform all of the basic life functions as the larger plants and animals do protests differ from each other in many ways size and shape are easy differences to see but in those protests that move the type of structures used for movement are important in identifying them blepharisma moves by means of tiny hair-like structures called cyia scientists call this kind of protest ayate parium is a common ciliate the cyia are extremely small and hairlike lined up in rows like the ores of a boat and are used to move the organism around some protests have a long whip-like structure called a flagellum in this case the tip vibrates rapidly moving the organism as you might expect these protests are called flagellates amoeba are very common protests that appear to move by changing their shape and flowing in the direction they want to go the extensions of their body are structures called pseudopods or false feet as it moves the amoeba is always ready to capture food all protests like plants or animals either make their own food or feed on others watch what happens to this smaller protest that swims in between two of the amoeba false feet the amoeba slowly flows around to enclose it and forms a structure called a food vacu where it is digested a type of amoeba called difflugia has a hard shell to protect it and only the false feet extend out of the shell as difflugia moves about another specialized structure in some of the protests called a contractile vacu serves an important function excess water entering the protest is collected in the vacu and is pushed out through a tiny pore in the cell which forms when the vacu contracts protests like other cells have a nucleus and in some cases more than one the nucleus contains the chromatin special types of molecules that are passed when the cell divides protests reproduce in a number of ways most cells just divide to form two While others reproduce sexually conjugation is a special type of sexual reproduction in cell division a single protest divides to become two eventually the two new protests will reproduce and so on some form large colonies or groups of cells through photosynthesis just like the Trees of the forest and the grasses of the Prairies volvox uses the energy of the Sun in the production of its own food from nutrients in the water diatoms are a unique kind of protest microscopic golden Jewels with unique body forms living in both fresh and salt water after they die their hard skeletons sink to the sea floor or are washed up on beaches where we can collect them for study they may also be buried and under great pressure form dious Earth which is used to filter impurities out of water and other liquids some protests have very close relationships with other kinds of protests this is parami berseria living within it are other smaller protests called chlorella which carry on photosynthesis and give the parami its green color the partnership benefits both protests one receiving nutrients while the other has a nice place to stay when parami braseria dies it bursts the chlorella green with chlorophyll are released and their forms are clearly seen with the aid of the microscope and Camera we have seen the many shapes sizes and colors of protests as well as the way they move their numbers in a single drop of water were more than we could count can you imagine how many there must be in a pond although most protests live freely in water some live within other organisms the soil that covers the continents of our planet is the home of many life forms including earthworms which in turn are home for protests these organisms live in the reproductive parts of the earthworm the protest does no harm to the worm and has a safe place to live cows are common place in our world the source of important foods for humans meat and milk cows eat grass but they cannot completely digest it without help once again protests are hard at work protests living in the cow's stomach help produce digestive chemicals which break down grass fibers without these organisms cows one of our major protein sources could not survive not all protest are beneficial to humans and to other organisms one of the most deadly is a tiny flagellate called tripanis found in the bloodstream it causes diseases which afflict millions of people in Africa and South America perhaps one day scientists will discover cures for the terrible diseases brought on by these tiny organisms although brief our journey with the aid of the microscope has taken us into a world unknown to our eyes the world of the protests an important part of the Great Web of Life on our planet [Music] now