AV Geeks 16mm Lunch 4-23-2024

e e for that for for is for is hello everybody I'm skip alimer welcome to the avgeeks lunchtime streaming show where we watch old 16 mm films from our collection and from uh other collections uh that was uh part of a project we've been scanning uh Coronet films for the people that actually own Coronet now they sent us 9,000 cans of film and we're about halfway done uh it's taken us a while but uh finding some great stuff unfortunately that scan that we did uh did not not have a soundtrack so we're going to track down the soundtrack if we can find it because there's some whacked out scenes in there that we love uh this next film life uh in a cubic foot of soil does however have um the soundtrack let's learn more enjoy [Music] there are living things all about us living things in the air and living things in the soil are grass and shrubs the only living things in soil as part of a science project these boys and their teacher are going to study a cubic foot of soil they have dug up and placed in a plastic container in a profile of this cubic foot of soil we can see a layer of subsoil and a layer of top soil growing out of the top soil are grasses and other plants this is called plant cover by carefully examining the layers of top soil and subsoil we can find living animals such as this white grub the larvae of a June beetle we can also find other animals that inhabit the soil communities of ants and larger animals earthworms are among the animals seemingly best adapted for living in soil how do living things depend on soil what are some of the Rel relationships between soil and plants and animals to find answers to these questions the boys and their teacher will examine the cubic foot of soil more closely now in the school science laboratory we're ready to look for relationships between living things and soil first we'll have to investigate soil more closely let's start with the subsoil layer what can we notice about its makeup we see that it is composed mostly of clay and larger particles such as Pebbles magnification with a hand lens gives a closer view of the clay and the bits of rock that make up the non-organic material in the subsoil this non-organic material may have come from a stream or a brook where moving water tends to grind rock into smaller pieces this is called weathering the rock is gradually reduced to coarse sand s fine sand and clay these non-organic materials tend to be found in the subsoil non-organic materials may be further broken down by the roots of plants as we know Roots do two important things they hold plants in place but the main function of roots would seem to be to supply water in certain chemical compounds from the the soil which the plants use to produce food materials some of these chemical compounds are found in humus a dark colored organic material in Top Soil let's examine humus to see what we can learn about its composition setting the microscope for low magnification we see that humus is made up of bits of decayed plant and animal matter this makes it organic now preparing another slide of a sample of top soil adding some water and using higher magnification we can see bacteria simple plants these are species of nitrogen fixing bacteria that live in soil these nitrogen fixing bacteria change nitrogen into soluble nitrates used by plants these bacteria act on the nitrogen in the air that penetrates the soil other kinds of nitrogen fixing bacteria live in the nodules of the roots of clover and other legumes so Clover and other legumes are especially beneficial to soil increasing its nitrogen content do we have nitrates in our soil sample chemists test for nitrates in humus in the following way some humus and water are mixed together in a test tube then an equal volume of Ferris sulfate is added now holding the test tube in an inclined position concentrated sulfuric acid is added at the junction of the acid and the other Solutions a brown ring forms this as chemists know indicates that the humus being tested contains a nitrate so we found nitrogen in the soil a chemical converted into nitrates and used by plants now we would like to find whether there is evidence of other living things in the soil several days ago these boys placed some moist humus in a patri dish here's what grew on the surface a mold if we investigate a sample of this simple plant under a microscope what can we see we notice that the mold is made up of a mass of threadlike stems called hyy the growing hyy of many moles enter the organic matter in the soil and help break it down the penicillium mold is sometimes found in soil too it is the source of a very useful antibiotic penicillin are the moles and bacteria we have seen the only forms of microscopic life found in soil this sample of damp soil was taken from the edge of a pond and kept moist let's examine some of it the wet soil sample is put on another slide here we see a species of blue green algae like bacteria and molds algae also contributes to the organic content of soil in addition to algae certain species of one- celled animals the protozoa also inhabit moist soil this is ugina one kind of protozoa found in moist soil the protoo we have seen are among some of the animals found in soil remember this grub we saw earlier it is the larval stage of the June beetle sometimes when we examine soil we may find an empty pupil case this pupil case was left when the June beetle grub or larvae emerged into its adult stage and flew away certain stages of the life cycles of many insects are spent in soil by digging further into a section of soil and carefully spreading it out for observation the boy has found aunt larvey and Aunt pupy grasshopper eggs and the Cocoon of an earthworm when earthworms hatch they become useful organisms in soil look carefully at this earthworm burrowing in our sample of soil burrowing help air Circ culate in soil these little Mounds on the surface of the soil are earthworm casts or wastes which also enrich the top soil with the hand lenss we may discover smaller animals in our cubic foot of soil here we see a ladybird Beetle here on the left is the pupa and on the right the larvae of a meal worm let's summarize what we've learned about our cubic foot of soil animal and plant matter Decay and become part of the soil as humus we've noted that humus is a material containing nitrates chemical compounds essential for plant life we've also noted how plants and animals contribute to the building of soil in the soil itself we found and identified a number of different plants and animals we found that our cubic foot of soil contained bacteria molds and algae along with larger green plants such as grasses and clover examples of animal life included insects worms protozoa both animals and plants living and dead contribute greatly to the fertility of soil and the soil in turn provides a basis for the growth of other living things the plants and animals that help make possible human life on [Music] Earth ugina ugen um yeah wonderful uh this next film has like a really HIIT Soundtrack This is another cornet film and I feel like this was made maybe around the same time uh but the color is also really good in this this is moving Goods in the community and uh tap along enjoy [Music] [Music] in every Community you can see Goods being moved from one place to another what does goods mean Goods is a name we use for many things our food our clothing the things we use in our homes are called Goods goods are carried on trucks right there are different kinds of goods and different kinds of trucks to carry them the trucks take Goods to many different places in the community we're going to see some of those places and find out why they need to have Goods brought to [Music] them of course we want to remember that trucks are only one of the ways that we use for moving [Music] Goods you can also see good being moved on a [Music] train there are a lot of different kinds of railroad cars because they have to carry different kinds of goods sometimes you can see the things the train is carry in every Community there are many places that need goods mean like homes hey there's a truck at my house let's go see what they brought when we buy something big or heavy we usually have it delivered on a [Music] truck trucks deliver Goods to many different kinds of homes homes in tall apartment buildings homes in smaller buildings [Music] things don't always come on trucks no not always but usually they [Music] do what are some more things that might be delivered to us [Music] many of the goods we need can be delivered to homes but not [Music] everything we go to a store to get them here's a big store a department store we can buy many different kinds of goods in a department store do trucks bring all these things to the store right big stores have places called loading docks where the goods they need are delivered all of the stores in the community have Goods brought to them to be sold there are many other places that also need goods for instance the places where people work to make things they're putting off a building they need things to build it with here's another place where people work to make things a factory what kind of goods do you think a truck might bring to a factory these sacks contain plastic material that will be used in making toys this kind of goods is called raw materials a factory turns raw materials into Goods that we can use what's in the boxes these are the toys that were made from the raw materials they're ready to be loaded on to another truck so we also need trucks to take finished goods away from a factory do they take them to a store now probably not right away most likely they'll go to a place called a warehouse into the warehouse go trucks carrying goods from many different factories the Goods will be kept here until a store needs them then out of the warehouse come big trucks that will take the goods to a store and from another part of the warehouse come smaller trucks that will take Goods directly to people's homes some factories use raw materials that are very large and heavy they have their own railroad tracks yes a railroad is a good way to bring heavy materials to a factory now they're unloading the railroad cars can you guess what the factory will make from these materials cars that's right this is an automobile assembly plant where are the cars going they're being loaded on speci special railroad cars to be carried away from the factory special trucks are also used to carry automobiles away from the factory there are many kinds of goods that must be carried on special trucks here's another special truck gasoline truck it's delivering gasoline to the gas station look he's putting the gasoline into the ground well not exactly there's a big tank under the ground that holds the gasoline here's another special kind of truck what's special about it it's a refrigerator truck that's because it's used to carry meat and meat will spoil if it's not kept cold this man is delivering another kind of food that also has to be kept cold fruits and vegetables are delivered to the store every day so they'll be fresh when we buy them so many kinds of trucks are used to carry goods from one place in the community to another trucks may also be used to bring goods from other communities a long distance [Music] away what are some other ways of bringing goods from other communities [Music] there are many ways of moving Goods some are faster than others some are cheaper some can handle loads that others cannot a community needs several kinds of Transportation they work together to bring us the things we need most Goods must be moved many times before they reach us this toy truck wouldn't be here here if there hadn't been a real truck to bring the raw materials to the factory where it was [Music] made and when it was done they put it on another truck and they took it to a warehouse and then away from the warehouse to a store where we can buy it whether we get the things we need at a store or have them delivered to our homes we all depend on the moving of goods in our community [Music] wow 1972 I think we agreed as a community that 1972 was the best time for educational films that was like the Pinnacle there's certainly a golden time in the 50s but 1972 it's a sweet spot uh stylistically let me geek out a little bit cuz that's what we we do here at a Geeks stylistically uh it's very interesting you had the narrator uh who's our traditional voog voice of God and then you have two kids chiming in and asking questions and making observations and that's a different style than uh most cornet films uh most cornet films excuse me um it's vog or it is is kids narrating or it's live uh sync sound where people are talking in the film that's that's rare that doesn't happen as much unless there's some sort of narrative that's there uh in place but um yeah the kids inter interjecting had a feel for me uh like Sesame Street Early Sesame Street had that same type of vibe um where but in excuse me with Sesame Street there wouldn't be an adult voice it would just be mostly kids talking so it's kind of interesting there's that shift in the 70s to having kids narrate and be the voice um because I think they realize that kids like listening to other kids um so uh let's uh do some measurement in physical science enjoy measurement in physical science brings to mind complex instrument instruments used with skill to get accurate comparisons accuracy is a prime objective in physical science whether we're determining the thrust a rocket will develop on a test stand the quantity of light received from a distant star or the intensity of radiation released in a nuclear reactor in measuring any physical quantity accuracy depends upon the particular instrument and the skill with which an instrument is used to demonstrate some of the principles involved in making accurate measurements of physical quantities we'll consider the three basic quantities of physical science distance mass and time let's start start with distance in this acceleration experiment the boys need to know the distance along this inclined plane the boys use a rather crude instrument a cloth measuring tape no matter how skillfully they use the tape it will be difficult for them to get an accurate measurement the tape sags when they pull it sufficiently tight to make it follow a straight line the soft material stretches slightly the crudeness of the instrument limits the accuracy no matter how skillfully the measurement is made by substituting a steel measuring tape the boys can get a more accurate measurement we can show other ways in which the skills of an observer and the quality of an instrument complement one another in this experiment involving intensity of nuclear radiation a certain degree of skill is required to measure distance even with a comparatively simple instrument this meter stick we'll measure the distance from the probe of the Geer counter to the piece of metal shielding that has been placed in front of a radioactive Source notice that the shield is not lined up with the end of the stick the end is worn so the first division is short this s s of error is eliminated by measuring between points farther up the scale another potential source of error is the thickness of the stick the scale is separated from the probe so that our reading of the scale changes as we change our angle of view this source of error is called Parallax it is inherent in the way we see things in perspective to reduce parallax a skilled Observer will turn the stick bringing the scale markings closer to the probe even now however there is a small space between the scale and the rounded end of the probe if the experiment requires greater accuracy we can select another instrument more appropriate for the job a mirror scale when the Observer is in the position where the mirror image is lined up exactly with the end of the probe his line of vision is perpendicular to the scale giving a more accurate reading our skill in using an instrument depends on knowing which instrument is most appropriate for a given job for example suppose we want to measure the thickness of the metal shield the metal is so thin we cannot use the smallest units on the meter stick because we cannot distinguish distances much smaller than a millimeter so in this case a more accurate instrument to use is the micrometer caliper to tell when the caliper is in contact with both sides of the shield we depend on our sense of touch we can measure the thickness of The Shield to within a 100th of a millimeter with the micrometer have you ever thought of a microscope as a measuring instrument with a microscope our sense of sight is extended and we can measure living cells that are only several thousands of a millimeter in diameter again it is the design and quality of an instrument combined with the skill in using it that results in an accurate measurement of distance in measuring mass the same principles apply in this impact experiment consider the mass of one of the balls how can we get an accurate determination of its mass first we need a set of standard metric masses for comparison a direct visual comparison of masses is not likely to be very accurate we could make an indirect comparison with the aid of an instrument such as a spring balance the balance is calibrated to show weights of the standard masses keep in mind that there is a difference between mass and weight when we weigh an unknown Mass we are comparing the weight of the standard with the weight of the unknown mass mass of an object at rest is always the same the weight is not weight depends on gravity and gravity of course depends upon the mass of the earth and the distance from its Center at the Equator this distance is greater than at the poles due to the Earth's equatorial bulge so if an object at one of the poles weighs 100 g at the Equator the same object will weigh about 99 and half G if an object is sent far enough away from the earth it may approach the state called weightlessness experienced by men in certain kinds of flight on the moon an object will weigh less than on the earth due to the moon's lower gravitational attraction since weight depends upon position if we wish to make an accurate comparison between masses we should weigh them at the same place to do this we select an instrument appropriate for the job the beam balance with a beam balance the standard masses are used in the actual comparison so the unknown mass is being compared directly with the standard masses when the mass is balanc we know that the quantity of Mass on each side is the same this is the principle of the beam balance beam balances like other measuring instruments are available with differing degrees of accuracy this one can measure a mass of 1,000 lb to within 1 2,000 of a pound the micro balance being used here is accurate to within 1 millionth of a g the quality of the instrument and the skill with which it is used determine the accuracy with which the Mass is measured to show how the principles we have observed apply to the measurement of time we'll use this stop clock which can measure to within 100th of a second for our example we'll consider the vibration of an inertia balance we'll measure the interval of time it takes for the mass to swing past the vertical rod and then back again we'll start the clock when the mass is exactly opposite the rod and stop it when it Returns the clock indicates the interval to the nearest 100th of a second but is this accurate watch as this student resets the clock and measures the interval once again see if you notice any sources of error what about the way he looks at the balance is Parallax a factor here what about his reaction time between seeing the mass pass in front of the indicator and pressing down on the start button aside from the variation between this reading and the last one our general knowledge tells us that reaction time interferes with the accuracy of the measurement realizing the limitations of his senses a skilled Observer May modify his instrument to compensate for this in this case by using a photoelectric device a projector will provide a beam of Light which will be received by a photosensitive cell the card will cut through the beam of light the edge of the card lined up with the center of the mass cuts through the beam of light and activates the photo cell the cell automatically starts and then stops the clock to which it is connected now the time intervals will be measured with greater accuracy this is another way of compensating for limitations of our senses a clock wired to a photo cell is just one of many instruments skillful observers have devised for getting accurate measurements of time to measure intervals between heartbeats scientists have developed the electrocardiograph this device compares the time between heartbeats with the time it takes the paper to move past the pen the oscilloscope is another device used to measure time the wave pattern shown on this screen indicates the intervals of time between fuel ignition in the cylinders of the engine time remember is one of the basic quantities of physical science the principles we have seen for measuring these basic quantities of distance mass and time apply equally well to other physical measurements whether our measurement problem requires a highly Specialized or a routine procedure the design and quality of our instruments must be appropriate to the job and we must use them skillfully to get accurate measurements of physical [Music] quantities oh yeah all right so I'm trying to set this up and I really realiz I haven't uh cabled correctly uh so I'm going to be a little bit off camera here uh cabling uh I've been uh to pay the bills we uh to really pay the bills and pay our staff we've been um doing uh digitizing work for other entities and so we've been working with uh somebody digitizing some women's soccer and so that's what I was using this workstation for uh I think I got this up let's see um because we're trying to meet a deadline Etc I think I got this going all right so this next film we have on the scanner it's a courtesy of Miss Cynthia Miss Cynthia brought us a uh I guess you can say in the comments Miss Cynthia where did you find these films were they on the street were they on your porch uh where did you find them uh this is fungi fungi let's see how they pronounce it enjoy [Music] an excellent opportunity to investigate a very interesting group of organisms occurs each year about 1 week after Halloween a pumpkin represents a large store of carbohydrates and proteins molecules rich in energy the source of biological energy is sunlight collected by green plants through [Music] photosynthesis this energy can be transferred to animals which feed on [Music] Plants a related method of acquiring energy is by absorbing nutrient molecules from decaying organic materials this lifestyle is the specialty of the fungi fungi includes such familiar organisms as mushrooms molds yeasts which are microscopic organisms often found growing on the surface of fruits and some more or less familiar parasites over 60,000 living species are classified as fungi and new ones are found each year until recently all of these organisms were class ified as part of the plant kingdom however fungi lack chlorophyll and so are unable to make food by photosynthesis also their cellular structure is quite different from plants in that fungi are made up of threadlike hyi each hyper may contain many nuclei whereas plants generally have but one nucleus per cell these are some of the reasons that many biologists prefer to place fungi into a kingdom of their own giving fungi independent status creates a classification breakdown of living things into five kingdoms the plant and animal kingdoms which include most of our familiar multicellular life forms the Kingdom Protista which is made up of single celled organisms such as protozoans and most algae the kingdom Monera made up entirely of microorganisms in which the DNA is not contained within a nucleus this group includes bacteria and blue green algae the most primitive living things and the kingdom fungi composed of multicellular organisms which lack photosynthetic pigments but with nuclei and cell walls and which reproduced by means of spores fungi obtain energy by digesting organic materials and then absorbing the digested products the dark areas indicate where digestion of the fruit is taking place after 6 days the fungi have nearly completed the decomposition process converting most of the fruit into fungal tissue and reproductive structures the breakdown is accomplished by the hyy which secrete digestive enzymes into the surrounding environment the digested nutrients are absorbed by the hyy and distributed throughout the hyl network [Music] once established the mold will begin producing reproductive structures called [Music] sporangia in this mold the sporangia are held aoft by means of rigid hyy the slight elevation will Aid in dispersing the numerous spores developing within each sporangium [Music] the constant flow of materials to the sporangium suggests that fungi like other life forms pour their energies into reproduction under drying conditions the sporangium will split open and release hundreds of Airborne spores each capable of beginning a new mold colony spores may also be transported by insects here a fruit fly attracted to the decomposing pumpkin accidentally picks up a load of spores traveling from one fruit to another the insect will inoculate each food source it touches the dispersal of fungi by means of spores has many variations molds which make their living by decomposing dead water animals have developed swimming Sports in the water mold's elongated sporangium the tight packed spores can be seen at maturity the spores are extruded through a pore at the tip of the sporangium where they form a Spore ball propelled by flagella the spores become active and many Break Free [Music] Guided by chemical signals the escaping spores will locate a bit of dead material settle and begin the growth of a new mold [Music] Colony spores are the asexual method of reproduction in fungi but these organisms also engage in sexual forms of reproduction [Music] here a female structure called an oogonium is developing within the oogonium a single large cell the egg is maturing responding to attractants produced by the oogonium the male structure called an antheridium approaches in a short time the antheridium has produced hyle fingers which clasp the [Music] female nearby another oogonium has developed several [Music] eggs male nuclei the equivalent of sperm penetrate the oogonium and fertilize each egg cell within hours the fertilized egg has developed a thickened outer wall these resistant zygotes can overwinter producing a new new generation of water molds the following spring now we can add another aspect to our definition of the kingdom fungi fungi are with a few exceptions sexual organisms competition for food in nature is usually severe even decomposers such as fungi and bacteria viy with each other for nutrients this situation has produced an interesting adaptation one that has proven very useful to mankind stacus epidermitis is a bacterium which can be easily cultured on nutrient [Music] augur penicilium notum a mold commonly found on fruits and cheeses also grows well on [Music] augur how will the two species behave in competition if the augur is inoculated with the bacterium and a bit of penicilium is placed in the center this is the result there is a clear Zone surrounding the growing penicilium Colony the multiplication of the bacterium has been inhibited by a substance produced by the mold the antibiotic penicillin in nature the production of antibiotics allows molds to stake out a territory in which to grow and reproduce by irradiating cultures of penicilium with ultraviolet radiation mutant varieties have been developed which produce significantly greater quantities of penicillin for use as medicine here a high yield mutant is compared against a wild type variety of penicilium the classification of fungi is based upon the methods used for Spore production we have been looking at the ficom my a group of fungi which produce spores in a sporangium other fungi the bidio mys use a different method of Spore production this group includes the organisms known as mushrooms or toad stools along with bracket fungi Coral fungi puff balls the bird's nest fungus and rusts and smuts which are destructive plant parasites the visible mushroom is but a short stage in the life cycle of these large bidio myates for most of its life the fungus exists in the soil as a tangled mass of hyy called mycelium spreading through the moldering humus secreting enzymes digesting and absorbing the nutrients released and undergoing sexual exchange of nuclei the mycelium may exist for years before organizing into the spore producing structure we call a mushroom if a mushroom cap is sectioned the Spore bearing areas can be seen lining the surface of the lamell or gills as they are often called the spores are produced on a club-shaped bidum which is the spor bearing structure which gives the group its name when mature the spores are fired into the air spaces between the gills and rain down for dispersal by wind a Spore print gives an idea of the vast number of spores which are produced in a 6-hour period a number of common mushroom species are poisonous to man unfortunately there is no known method of telling edible mushrooms from poisonous ones except by correctly identifying them by species for example would you eat this one how about this one or this one well don't eating these mushrooms can result in death unless you can correctly identify edible species it is prudent not to experiment with eating wild mushrooms the third method of Spore production belongs to the cup fungi or asomi seats a section through the cup of an asomi seat shows the spore producing structures each Sac or ascus produces eight spores the ascus is a kind of Spore Cannon which can fire the mature spores into the air for wind windborn dispersal but the real artillery pieces of the kingdom are the fungi which live in the feal material of herbivorous mammals in order to be assured of germinating in manure FAL fungi must find ways to optimize their chances of getting their spores into the animals food this species produces a ball of spores responding to light the cannon is aimed osmotic pressure builds up and with a pop the Spore ball is hurled a meter or more beyond the home manure pile sticking to a blade of grass the spores have an excellent chance of being ingested by a grazing animal we have examined fungi from three main groups the ficom mys which produce spores in a sporangium the bidum myits which produce spores on a basidium and the Asom myets which produce spores in a sack like Asus most of these organisms are beneficial decomposers some fungi however have taken up parasitic life the gross deformation of this ear of corn is caused by a parasitic fungus which has turned the corn kernels into sacks of spores even the lowly amoeba can become host to parasitic fungi the spherical structures called hostor are used by the Paras site to invade and anchor into the host [Music] cell fungal organisms have evidently been around for a long time however their origin is obscure since most fungi are soft-bodied and leave no conclusive fossil record there is one group of contemporary life forms which offers a clue to the mystery of fungi origin these are the slime molds organisms which have at times been classified as fungi and at other times as protests in this stage of its life cycle the slime mold is moal flowing over the surface of the log feeding on bacteria and bits of decomposing [Music] material Its Behavior is much like that found in a familiar group of protests the amias [Music] slime molds however have undeniably fungal-like characteristics they produce sporangia which liberate Airborne spores since they have characteristics in common with both protests and fungi the slime molds may represent an evolutionary link between these two major divisions of [Music] Life the kingdom fungi including the organisms which produce our antibiotics useful food items with proper caution agents of spoilage and parasites but far overshadowing these human interests the fungi fill a vital niche in the Ecology of our planet the recycling through decomposition of nutrients in the Living [Music] World W sorry about the cow poop during lunch um well I mean so I had a choice between two uh remaining films that Miss Cynthia uh found and sent uh one was a funi fun guy the other was alcohol crisis for The Unborn which I felt like was going to have some footage that was going to be problematic um uh so oh yeah I guess Rotting Flesh too in that film um yeah sometimes you know you you pull out a film you don't know what it's all about but uh thanks for bearing with us uh [Music] so join us tomorrow tomorrow's Wednesday um we have some more 60mm films to watch um thank you Miss Cynthia thank you Jeremy for uh donating be the super thanks button that's a way you can support us sending us films is a way you can support us um you can also go to ko-fi.com avgeeks or patreon.com avgeeks uh I just realized I did some math and if this shelving system works out I'm probably going to have to buy 10 more shelving units and each one of those is $200 so um yeah so I'll be pushing the fundraising aspect of of what we do a little bit more uh because it helps it certainly helps and patreon is one way that we get do that and also we will forego coffee so we can buy shelvin units cuz we got a couple of months to get everything out of the archive before we start renovating anyways oh that's an interesting idea Tom if people sponsor the shelves will you put their names on them yeah let me think about that um that's a possibility we might uh give naming rights to individual shelves and then there might be things associated with that which will be fun um yeah I'll think about that anyhow thanks so much for watching and contributing and uh commenting and letting your eyes uh be exposed to all sorts of interesting and gross things uh we will be back tomorrow um take care and have a great rest of your day bye bye