Introduction to Taxonomy - Video Tutorials & Practice Problems
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concept
Introduction to Taxonomy
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In this video we're going to begin our introduction to taxonomy. And so taxonomy is defined as the branch of science that classifies, identifies, and names all living organisms. And so, it turns out there are actually 8 categories that are used to classify all life. And notice that down below in our image, we're showing you all 8 categories used to classify all living organisms from the most inclusive category on the far left which is the domain, and the three domains of life include all living organisms, making it the most inclusive. And, all the way to the right notice we have the least inclusive category of species. And so the species only includes one single type of organism. And so, the 8 categories of life from most inclusive to least inclusive are domain, kingdom, phylum, class, order, family, genus, and species. And so, one way to help you guys remember the 8 categories that classify all living organisms from most inclusive to least inclusive is by remembering this memory tool. And that is, dear King Philip came over for great soup. Dear king Philip came over for great soup. And what you'll notice is that the first letter of each of these categories is a unique first letter, and so that allows us to create this memory tool, and, help us remember the 8 categories from most inclusive to least inclusive. And so notice here we're showing you an image of King Philip who came over, for some great soup. And so if you can remember, dear King Philip came over for great soup, you'll be able to place these 8 categories in the correct order from most inclusive to least inclusive. And so this here concludes our brief introduction to taxonomy and I'll see you guys in our next video.
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Problem
Problem
Which branch of biology is concerned with the naming and classifying of organisms?
A
Bioinformatics.
B
Taxonomy.
C
Genomics.
D
Evolution.
E
Biology.
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concept
3 Domains of Life
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5m
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So from our last lesson video, we know that there are 8 categories of life used to classify all living organisms. And the most inclusive of those eight categories is the domain. But really, there are 3 domains of life, and that's the focus of this video. So once again, the broadest and the most inclusive categories of life are the 3 domains, which we have numbered down below. And so the first domain of life is domain bacteria. The second domain of life is domain archaea. And the 3rd and final domain of life is domain eukarya. Now domain bacteria and domain archaea can be grouped together because they both consist of what are known as prokaryotic cells. Now later in our course, we'll talk more about these prokaryotic cells, but for now, what you guys should know is that these prokaryotic cells lack an organelle called the nucleus. Now the eukaryote domain, on the other hand, these consist of eukaryotic cells. And once again, we'll talk more about eukaryotic cells later in our course, but for now, you should know, that eukaryotic cells will actually contain a nucleus. So you could think of them pretty much as being the opposite as prokaryotic cells, which lack the nucleus. Now, if you take a look at our image down below, what you'll notice is we are showing you the 3 domains here, domain bacteria, domain archaea, and domain eukarya. And this portion right here of the image, scientists will refer to as a phylogenetic tree. But for our purposes here in this video, you can just think of it as the tree of life. And it's showing us where all organisms, all living organisms, where where they fall and how they can be categorized. And so on this horizontal axis here, what we have is time. And so the further to the left you are on the axis, the further in the past you are. And as you make your way towards the right of the image, you make your way towards the present. And so in today's, present time, there are these 3 domains, domain bacteria, archaea, and eukarya. However, if you go way back into the past, there is evidence that suggests that all life came from a common ancestor. And this is just a theory, so, it can never be proven true, but there is lots of evidence that supports this idea. And so what you'll notice is that the theory shows that, life came from a single common ancestor, but over time as we make our way to the right, notice that through natural selection and evolution, these three different branches of life came to exist, the 3 different domains. Now once again, domain bacteria and domain archaea can be grouped together, which is why we have these brackets around them, and they can be grouped together because they both consist of prokaryotic cells. So they can be called prokaryotes. And as we mentioned up above, prokaryotic cells lack an organelle called a nucleus. But, also, prokaryotic cells are unicellular, meaning that they're only made up of just one single cell. Whereas down here, what you'll notice is with the domain eukaryote, this is where humans fall, like ourselves. And, these are going to be consisted of eukaryotic cells, so they're referred to as eukaryotes as well. Now eukaryotes, although you may think of humans as being multicellular, eukaryotes can either be unicellular or multicellular. And so it includes all multicellular organisms that you can think of, but it also includes some unicellular organisms as well. And so that's something important to keep in mind. But once again, later in our course, we'll talk even more about these prokaryotes and eukaryotes. For now, you should focus on the 3 domains of life, domain bacteria, domain archaea, and domain eukarya. And so this here concludes our introduction to the 3 domains of life. And as we move forward in our course, we'll be able to get a little bit of practice with this idea. So I'll see you guys in our next video.
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example
Introduction to Taxonomy Example 1
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3m
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Alright. So here we have an example problem that wants us to fill in the 2 blanks here in this sentence using one of these 4 potential answer options down below. And the example problem says, according to the diagram over here, A is blank whereas B is blank. And so when we take a look at this diagram over here notice that on one end what we have is a and on the opposite end of the diagram, what we have are the 3 domains of life, domain bacteria, archaea, and eukarya. And so, notice that A is right here at this position and b is specifically pointing to this position right here. And so when we take a look at option a here it says, that a is the most recent species to evolve on earth. But, of course, we know from our last lesson video that when we see a diagram like this one, that it's actually based on time and, furthest to the right, what we have is the present. So this represents the present. And as you go backwards, we're actually going into the past. And so, the three domains of life are what we have in today's present world. However, going backwards into the past, this is where we started. And so what we're saying is that, a, by saying that it is the most recent species to evolve on earth. It's not really recent at all if it's way back in the past. A, is in the past and, the most recent species to evolve are going to be in the present, somewhere towards the right of the diagram. And so what that means is we can eliminate answer option a and answer option b since both of them say that for this first blank a is the most recent species to evolve on earth, and we know that's not right. Instead, we know that a is going to be the common ancestor of all life, so it's either going to be option c or option d. That's the correct answer for this problem. And since both c and d have the same thing for the first blank, we need to take a look at, what it says for option b. So, b is, this option here says, the common ancestor of bacteria and archaea. And, this option here says that b is the last common ancestor of archaea and Eukarya. And so when we take a look at b, again, it's pointing to this specific location right here. And so, this is referring to the closest relationship between archaea and eukarya. The closest relationship between archaea and bacteria would be up here. So if you were to trace this back, this is the closest place that they meet. And so, what that means is we can eliminate answer option c because it says that b is, the common ancestor of bacteria and archaea, but that's not true of b. That would actually be up here. And so that only leaves answer option d here as the correct answer. And so, b is going to be the last common ancestor of archaea and eukarya. That's where, they connect most recently right here. And so d here is gonna be the correct answer for this example problem, and that concludes this example solve. See you guys in our next video.
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concept
Kingdoms of the Eukarya Domain
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In this video we're going to introduce the kingdoms of the Eukarya domain and so we need to recall from some of our previous lesson videos that organisms in each domain can be further subdivided into the kingdoms. And so it is important to note that the other domains including Bacteria and Archaea also have their own respective kingdoms, but in this video we're focusing specifically on the kingdoms of the Eukarya domain. And so domain Eukarya actually has 4 kingdoms and you can see these 4 kingdoms down below with these 4 boxes in our image. And so the first kingdom is going to be Kingdom Animalia which is going to include tigers and lions and elephants and insects and me and you of course and so these are going to be multicellular organisms that fall within Kingdom Animalia. Now the next kingdom that we have is Kingdom Plantae, which as its name implies is going to include all of the different types of flowers and plants and trees and things of that sort and these are also going to be multicellular. Now the next kingdom that we have is going to be kingdom fungi, which is going to include fungi such as mushrooms as you can see here and these are mostly multicellular but there are some unicellular examples. And then the 4th and final kingdom of the eukarya domain are the, protista or the protists and these are going to be either unicellular or multicellular. And so, they can be either or there are examples of unicellular and multicellular protisa. And so domain, eukarya as you can see here, it includes multicellular organisms, but it can also include some unicellular organisms as well. And so this here concludes our brief introduction to the kingdoms of the eukarya domain and we'll be able to get some practice applying these concepts as we move forward. So I'll see you all in our next video.
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example
Introduction to Taxonomy Example 2
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So here we have an example problem that's asking which of the following kingdoms is not part of the eukaryotic domain. And we've got these 4 potential answer options down below. Now, of course, we know from our previous lesson video that kingdom Plantae certainly is one of the kingdoms of the eukarya domain. So because it is and we're looking for the one that is not, we can cross off option a. And the same goes for option b, kingdom Protista, we know for sure is going to be one of the kingdoms of the eukaryote domain from our last lesson video. So we can also cross off option b. And once again, option c, kingdom fungi, we also know is one of the 4 kingdoms within the eukarya domain. So we can cross off option c. So then, of course, this leaves option d here, kingdom Eubacteria, bacteria in it, which we know is an entirely separate domain from the eukaryotic domain. And so, option d here is the only one that is not, part of the eukaryotic domain. And so notice that there are 3 domains here that are listed that are part of the eukaryotic domain. And the 4th one that is not listed here is kingdom Animalia, which is the one that humans, you and I, fall into. But for now, option d here is the correct answer for this example problem, so I'll see you guys in our next video.
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Problem
Problem
The proposal that one type of organism can change into another type over a long period of time is known as:
A
Creativity.
B
Evolution.
C
Natural history.
D
Preconception.
E
Preservation.
8
concept
Categorizing Life Based on Energy Acquisition
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5m
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In this video we're going to introduce yet another way that scientists can classify living organisms and that is through categorizing life based on energy acquisition. And so scientists can categorize living organisms into 3 classes just based on how those organisms acquire their energy, and so down below we have the 3 classes that group organisms based on how they acquire their energy. And so, the first class is going to be the Producers, and these producers are also sometimes referred to as autotrophs. And so, as their name implies these producers are going to be organisms that acquire their energy by producing or making their own food. And so the root auto in autotrophs is a root that means self and so they make the food themselves. Now, the second class is going to be the consumers and so the consumers are also referred to as heterotrophs and as their name implies these consumers are going to be organisms that acquire their energy by consuming or eating other living organisms. And so the root hetero and heterotroph is a root that means different. And so you can think that they must acquire their energy, through eating other organisms or different organisms. And so the 3rd class here is going to be the decomposers. And so these decomposers as their name implies are going to be organisms that acquire their energy by decomposing other organisms, and acquiring energy from the waste of other organisms and the dead organisms as well, acquiring energy from dying or dead organisms. And so when we get to our image down below we will distinguish between these 3 different categories of organisms based on how they acquire their energy. Now it is important to note that most of the energy that's utilized by living organisms is going to originate from the sun And we'll be able to see that down below in our image. And also it's important to note that with every single energy transfer, or with every transfer of energy, some of that energy is going to be lost as heat. And this is an idea that we'll get to talk more about later in our course when we're talking about the laws of thermodynamics. But for now, let's take a look at our image, where we can reinforce some of these ideas that we've discussed. And so notice in our image over here what we're showing you is the sun is over here on the far left which is about 93,000,000 miles from the earth and the sun is, going to have sunlight and that sunlight will be able to travel 93,000,000 miles all the way to our planet where there are organisms that are capable of capturing the energy from the sun and using that energy to create their own food. And so this is going to represent the producers, which you might recall from earlier in our video are sometimes referred to as autotrophs as well. So you could also put autotrophs in this blank as well. And, what you'll notice is that the yellow arrows in this diagram represent energy and the green arrows represent matter. And so notice that as the energy is transferred from the sun to the producers, there is going to be a loss of energy as heat and again, that is what this line of text here is referring to and again, this is an idea that we'll talk more about later in our course when we're discussing laws of thermodynamics. Now these producers, can be consumed by consumers and so over here we have this little bunny rabbit which represents our consumers. And so the consumers are also referred to as heterotrophs and they obtain their energy by eating other organisms. And so this bunny rabbit will eat the producers or eat this, grass to obtain its energy. And so notice that energy and matter are both being transferred from the producers to the consumers. And notice here that there is heat being lost as well and that occurs with every transfer of energy. And then of course as sad as it might be eventually this cute little bunny rabbit here is going to pass away and when this cute bunny rabbit dies, there are decomposers that are capable of acquiring energy from the dying organisms. And so down here what we have are the decomposers. And so here we're showing you some fungi, that are serving as the decomposers. And so it is able to acquire energy and matter from the dying consumers, as well as acquire energy and matter from the dying producers. Now what you'll also notice is that when these decomposers die, they will release nutrients into the soil and then the nutrients that are in the soil can be utilized by other living producers, and you can see the cycle of matter throughout this and the cycle of energy. But notice that the energy source for all of these living organisms for the most part is going to originate from the sun. And so, this here concludes our brief lesson on how, living organisms can be categorized based on their energy acquisition and and we'll be able to get some practice applying these concepts as we move forward. So I'll see you all in our next video.
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example
Introduction to Taxonomy Example 3
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1m
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Video transcript
Alright. So here we have an example problem that wants us to complete the sentence here using one of these 4 potential answer options down below. And the example problem says autotrophs are also called either consumers, synthesizers, producers, or carnivores. Now of course, what we need to recall from our last lesson video is that autotrophs are going to be organisms that are going to create their own food. And so they're able to create their own food using nonliving things. And so, you can see this auto prefix here, is one that means self. And so, when it has autotroph, it's basically saying it can create their own food on their own by themselves, for for instance. So another, name for autotrophs, of course, we know from our previous lesson video, is going to be producers, and that's because producers produce or create their own food. So the correct answer is going to be option c for this example problem. Now recall that consumers are going to have to consume their food by eating other living organisms. Synthesizers is not really, the term that we use to refer to these. And then carnivores are going to be organisms that eat meat. And so, we did also did not really talk about this in our previous lesson video, so we should have been able to eliminate that one. Once again, auto troughs are also called producers, and that concludes this example. So I'll see you all in our next video.
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Problem
Problem
Biologists can divide living organisms into two groups: autotrophs and heterotrophs, which differ in _________.