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Current time:0:00Total duration:12:12

Autotrophs & heterotrophs (nutrition modes)

Video transcript

why do these plans in my balcony need sunlight why is this Apple rotting and why does my head it's so much to answer these seemingly random questions we need to figure out the modes of nutrition basically what are the different ways of getting food and that's what we'll do in this video so based on how different living things get their food we can classify them into two categories producers and consumers so producers as the name suggests they are the ones who can produce their own food most examples involve the green trees and plants and all the green stuff around you and some bacteria as well and how do they make their own food well they do that by using the energy available from their surrounding for example plants and all the green things can use the energy from the sunlight to make their own food and you may have heard of this process called photosynthesis which we'll talk about in more detail in future videos but that is the reason why I need to expose these plants to sunlight because that's from that's how they make their own food and you and I are not producers because we can't make our own food like that so what are we well if you're not a producer you are a consumer consumers as the name suggests are the ones that consume others that eat others for food you and I are consumers my friend and most animals and insects that you are familiar with and even most bacterias they're all consumers either we eat vegetables and fruits or we eat other animals like chicken or fish or maybe eggs so anyways producers make their own food consumers eat others now before we proceed let me tell you their biological names right we need to give in biology everything has a technical name right so the technical name or the biological name of producers is autotrophs the word Auto means self and troughs means nourish so this means they can self nourish they can make their own food they can feed themselves self nourish on the other hand consumers their biological name is heterotrophs the word hetero means others dross means again nourish so like the name says they can't self nourish they relies on others to nourish themselves you and I and donkeys are heterotrophs insects and most bacterias heterotrophs now guess what based on how heterotrophs eat we can further classify them into three categories challah zoic separate ropes and parasites again let's look at each one in detail challah zoic are consumers which digest their food inside of their body you are a hollow zoic I am also hollow zoic most animals and insects were all holeczek because we eat and then the food gets digested inside our body and we are called so because the word Hollow means whole in the sense we eat whole food okay what does that mean take an example of an apple it doesn't say that you have to eat the whole Apple but even if you take a slice of an apple then that Apple can has some constituents right like it has for example sugars then it has some proteins maybe it also has some vitamins and so many other constituent these dots just represent constituents okay now when you eat this slice of Apple you take in all the constituents inside your mouth right that's so that's the whole that's the meaning of whole that's the meaning of whole oh you're eating this whole thing and then once it goes into your body then your digestive system breaks it into its constituent particles right that's the whole idea behind whole azoic these are the animals that digest their food inside their body now in order to be a hollow zoic you need to have a pretty good digestive system so that you can break down whatever you eat inside your body but what if you don't have a good night system then what happens well then you become a separate rope separate ropes are the ones that don't have a good diet system and as a result they digest the food outside of their body and then eat it and as we will see it's these guys who are responsible for rotting and decaying things and they include most bacteria and mushrooms mushrooms is a very specific example in general these are fungus right so bacteria and fungi fungi is plural fungus is singular so bacteria and fungi are the separate ropes they digest the food outside of their body and they're there everywhere okay I mean if you take that piece of apple and let's just leave it outside don't eat it then pretty soon you will find these bacteria and fungi will start attacking it so let's say these bacteria start attacking it now since they cannot digest the food inside their body because they don't have a very good digestion system what they do is they try to digest the food outside how do they do that they spit all the enzymes or the acids needed to break down the food right so as they spit these enzymes and acid chemical reactions take place and the food gets digested then in there and so this Apple starts getting broken into its constituents and then once it's broken then these bacteria will start absorbing these constituents okay but why does it rot and start smelling well that's because whenever digestion is happening whenever chemical reactions are happening some by-product is created right and it's these byproducts that start making things rot and that's what makes the whole thing smell as well and because of that more insects get attracted and now you can't eat this and this sounds very disgusting right but what's interesting is a similar digestion process happening in our bellies as well even when we digest food all this stuff is happening but because it's inside our body we don't smell it but if you throw up if you warm it then you can smell it I know it's pretty disgusting sorry but when you warm it basically you are vomiting out digested food with all these byproducts and you know even that smells right so we digest the food inside but these support ropes digest the food outside and that causes things to rot and that's the same reason why this Apple is rotting it's being digested by these separate rows another example is you may have seen if you keep bread outside for some time then they will start growing this fungus over here the fungus are digesting it outside now and your teeth also gets decayed for the same reason there are a lot of bacteria in our mouth and when we eat food the food gets stuck in the teeth and then they start getting digested by the separate ropes and that's why I always brush my teeth twice everyday and just a small thing okay after learning this I used to feel they are so annoying I mean if they were not there I wouldn't have to brush my teeth things wouldn't rot at all won't that be awesome no because guess what they also feed on the dead they are the ones that make sure to decompose all the dead stuff right so if they were not there then all the dead things like the dead animals and plants and everything would just pile up you cannot imagine what earth would be so thanks to them they decompose all the dead stuff as well and recycle all the nutrients make sure they go back into the nature which can be reabsorbed by the plants reused to make more food they are super essential for our environment and the words appro itself means rotting and that's why they're called separate ropes because they eat on the dead and decay and make them rot okay and finally what if you can't digest food at all whether inside or outside then what then you become a parasite parasites hardly digest any food then how do they get their nutrients well they depend on a host meaning another living organism for example this leech is a parasite it gets stuck to my leg let's say and then it starts sucking my blood now my blood already contains digested food and so it just starts getting nutrients from my blood directly so you see they don't have to digest anything so in that case since they are depending on me I am their host similarly my head is correct I have to scratch my head so much because there are some parasites on my head Lysa's are examples of parasites as well they also suck on the blood from the scalp again I am their host so parasites can either live on the surface of their hosts like leeches and lysis or they can live inside them as well for example tapeworms and drown worms live inside intestines so even though you may be healthy you have these inside your intestines okay and guess why are they there well because again intestine is where most food is already digested and so they can just eat that and so the word para kind of means alongside in the sense they're eating alongside its host so whatever I eat they goes to these guys as well now one important thing about parasites is I should think they're trying to kill me but no they're not trying to kill me they want me to be alive so that I can keep on feeding them for their entire life so parasites don't try to kill their hosts but they end up harming their hosts for example when this lead starts sucking on my blood they rupture the skin because of these lysis I am getting my head is getting itchy tapeworms and Ramos can cause my stomach to ache so they are definitely not trying to kill us but they end up harming us and again I should think parasites are pretty useless and many scientist you should think as well but recently we realize even they are pretty useful for example some scientists believe that the worms in our intestines actually help in boosting our immunity over there another example some leeches are useful in removing infected blood from our body and would you be surprised if I told you that fifty percent of all the species of living things on our planet are parasites that's right there are a lot of parasites on our planet almost every living thing has a parasite inside or on top of it anyways that's pretty much it so let's quickly look at what we learned there are two basic kinds of living beings autotrophs who generate the food themselves using the energy from the surrounding and the heterotrophs who can't produce their own food so they eat others and based on how you digest the food heterotrophs can be further classified as hollow zoic who if you take the whole food inside and digest it inside your body most animals and insects come under this category and you need a pretty good digest system for that but if you don't have a great digest system no worries you become a Safra Troop then you just digest the food outside of your body and then you must make things rot they are the decomposers they are the ones who eat on the dead and the decaying animals most bacteria and fungi and finally if you can't even do that then you just become a parasite just stick yourself to a host or live inside of them and then you get free digested food they might harm you but most of them have no intentions of killing you