[Music] welcome life science learners to another lesson trusted you guys are well and excited about today in our lesson today we're going to be focusing on nutrient cycles we're going to space special attention to the water and the oxygen cycles as the heads up there are four different cycles that we look at the water cycle the oxygen cycle the carbon cycle and the nitrogen cycle so why are these referred to as nutrients let's try and understand the context of where these nutrients are so carbon oxygen water and nitrogen are the essential organic compounds that we need are the essential elements that we need for organic compounds and let's try and understand that so these are essential elements that we need for most of our biological processes and hence it's important that we understand what are the events that happen that ensures that the levels of these fluctuate or return back to normal in the earth so it's important that we recognize that a cycle is a series of events that constantly occurs and so let's look at that concept as we unpack some important terminology before we get into the concepts of looking at the different cycles so unpacking terminology is crucial and i always always mention that this is something that you must do we're then going to spend some time looking at an overview of the nutrient cycle with relation to what atmospheric gases are so it's important that again the context of this is all in ecology if we look at ecology it's a study of the relationship between plants and animals and with each other and the non-living environment and that's important for us to be able to understand is that the abiotic factors are factors that influence our nutrient cycle so we're going to need to understand how these cycles influence life or the biotic factors when we talk of the term ecosystems we again referring to a specific area in which the abiotic and the biotic components interact with each other and are interdependent and this is important in that we're looking at how the biotic factors and the abiotic factors collectively function with each other and with their environment guys it's important that we mention the term abouttic and this often comes up when we studying ecology again it's the non-living components of an ecosystem that make up the air barting components and these would include soil climate temperature sunlight and water and we're going to spend some time looking at water today we're going to look at the biotic components and how they influence the the ecosystem and so these these would be the living components in an ecosystem guys the next component is the biosphere again this is part of the earth where humans and other organisms are able to live and interact with each other as a recollection of what we've done in the past the biosphere refers to the three components that make up earth and this would refer to the atmosphere the hydrosphere and the lithosphere and when we look at these we're going to spay special emphasis today on the atmosphere and how the oxygen cycle occurs the nutrient cycle as i mentioned refers to a repeated pathway of a particular nutrient or element from the environment through one or more organism and back to the environment so again when we talk of cycle it refers to the movement in a continuous process and in this case we're going to look at nutrients and how they are cycled through the environment either through the living components and the non-living components and hence we refer to them as the nutrient cycle as i mentioned in our lesson we're going to focus on the oxygen cycle this is the cycle whereby the atmospheric oxygen is converted to carbon dioxide in animals during respiration and regenerated by green plants in photosynthesis so a major component of this lesson would be the oxygen cycle and we've got to look at what processes produce the oxygen what processes use up the oxygen and how that balance is maintained in the atmosphere we also will spend some time looking at the water cycle again the water cycle is also called the hydro logic cycle again the word hydro referring to water and the process that are involved in the continuous circulation of water in the earth and atmospheric systems so the water cycle again would refer to how water is processed in different forms and returns back to the water cycle again let's unpack the nutrient cycle in detail so the biotic components and ecosystem depend on the abiotic components as we mentioned the abiotic components form the essential nutrients that biotic components need when we refer to the nutrient cycle it's important that we understand that the nutrients need to return back into the batting components so that these can support the living components in an ecosystem nutrients are obtained from the environment and are used by living organisms to grow reproduce and stay healthy and that's important that we recognize that this nutrient supply needs to constantly be replenished the most important elements that are required by organisms are oxygen carbon and nitrogen and these are known as your macro nutrients so again in the context of living organisms producing organic compounds carbon oxygen and nitrogen are the essential macronutrients that are needed for these important processes we also need to recognize that there are some trace elements and these are elements that are required in significantly smaller quantities and these include magnesium sulfur iron and a few others and these are important micronutrients that are important in the production of some of our organic compounds again the term micro referring to required in small quantities these are important elements as they produce organic compounds such as carbohydrates lipids proteins and other important biological compounds and without these it would be seen that we would not be able to sustain the life forms on earth the nutrient cycle make them available for reuse over and over again nutrients are cycled through the bodies of organisms and the ecosystem what is also required by organisms and this is an important component of life it's important that before we look at the oxygen cycle that we unpack what the atmosphere is made up of when we look at atmospheric gases we know that it is made up of different types of gases we have oxygen which makes up 21 percent of the atmosphere carbon dioxide 0.04 percent and nitrogen a significantly large percent of 78 with the other gases making up approximately one percent of that we know that oxygen is important for respiration for photosynthesis and for filtering out sunlight so that protects organisms from the harmful and strong sun rays again if we look at the combination of the different gases we see that the nitrogen is a significant component it's important that we recognize that these ratios of substances or gases that make up the total atmosphere remain approximately the same of recent in the last 100 years we've noticed that there's been an increase in the carbon dioxide levels and we will talk about that in a little while and so this is important that we understand that the concentration of these gases have remained relatively stable for a long period of time all living organisms except anaerobic bacteria need oxygen and we see that they need it for an important process called cellular respiration however we know that the green plants require carbon dioxide for a process of photosynthesis a substance like nitrogen in the air is important for all organisms in the process of protein synthesis guys as we wrap this segment up we've looked at what the significance of nutrients are in the production of organic compounds you guys have been a good audience have a little break and i'll see you in a bit [Music] you