this right over here is a picture of Earth not likely a surprise for most of y'all but we're going to talk about in this video and future videos is how we can view Earth as a system many of y'all might be familiar with the term system we talk about systems as a bunch of things interacting together in very very complex ways now the first division that we can think about the constituent pieces of the system we could think about what is living and what is not living and that's where the title of this video comes from biotic and abiotic factors now what do you think biotic means and I'll give you a hint it has the word bio in it which refers to life well a biotic factor is a living Factor so this is a living Factor now what's a living factor in a system for example our bodies are a system our bodies are alive but you also have biotic factors within that system for example you have gut bacteria inside of your intestines that bacteria they are they can live on their own if they needed to but they are also part of your body's system so the bacteria in your gut is a biotic factor and some of you might be saying hey yeah sometimes when I'm sick my parents have given me antibiotics and antibiotics are against living factors that are in your body now antibiotics are usually if you have bad bacteria that are floating around you in your blood or some other place that you want to get rid of but it can also affect your good biotic factors say the gut bacteria that you actually need to help with your digestion so we now know that a biotic factor is a living Factor so what do you think a biotic means means well generally when you have a in front of something it means not or the opposite of so an abiotic factor is a non non living Factor now if you're thinking about an abiotic factor inside of a system it might be the soil around you it might be the air pressure the molecules it might be the water pressure the temperature things that are actually not living and you could imagine that these in many systems will interact with each other so now that we have the basics of living factors and non-living factors biotic and abiotic let's start to break down Earth as a system into some of the highest level systems that people will describe it and these tend to be described as spheres now why spheres well Earth itself is a sphere and the four main spheres that earth scientists biologists other scientists will talk about are in no particular order the atmosphere which is probably a term that you have heard of and the atmo prefix is referring to all of the air around the earth we have about a 60 mile thick layer of atmosphere Now 60 M sounds thick to us but it's a very thin layer if you think about it from Earth's point of you can barely see the little thin atmospheric layer in this image of Earth that I got from NASA but the atmosphere is all the gases that surround the Earth and why is it a sphere if you don't consider all of the water all of the land all of the living organisms but Earth were to somehow maintain its shape well then that air all of the gases around the Earth would still be a sphere what other spheres are there well there's the biosphere which you can imagine is all of the living organisms on Earth so once again remove all the gas or don't consider the gas the land and the water but if all the living organisms stayed in place where they were and we're talking about trillions and trillions of organisms all over Earth they are for the most part at the surface or very close to the surface of Earth it would still resemble a sphere and then another sphere that we could consider is all of the water not only on the surface of the Earth but also below the surface of the Earth the hydrosphere so when you look at this picture it's obvious that the oceans and seas are part of that but also lakes and rivers and actually any form of water we could even be talking about precipitation we could be talking about rain we could be talking about icebergs because that too is water and then the last sphere which would really make up the bulk of the mass of Earth all of the interior and surface of the Earth including the Rock the continents in the ocean floor well then you are talking about the GEOS spere all of the nonwater non- gas non-living things that make up Earth which is really most of Earth