eukaryotic cells unlike procaryotic cells are those cells that contain a nucleus as well as other membrane bound organel and eukariotic cells include animal cells and plant cells as well as protist and fungi and in this lecture we're going to focus on the structure of the eukariotic cell we're going to discuss different types of organel that exist within that eukariotic cell and let's begin with the outermost structure that every single eukaryotic cell has it's the cell membrane so basically enclosing the entire cell and everything found inside that cell is a semi-permeable phospholipid by layer a cell membrane that plays a role in cell transport it basically allows things into the cell and out of the cell it also functions in cell communication as well as protecting the cell from outside sources of harm now now other types of eukaryotic cells not all but some eukaryotic cells for example plant cells also contain an additional second protecting barrier known as the cell wall the cell wall protects plant cells and it also gives them the shape and structure now let's move on to basically the organel that defines the eukariotic cell known as the nucleus the nucleus is basically an organ now that contains the genetic information and the nucleus contains its own phospholipid by layer that is called the nuclear envelope or the nuclear membrane to differentiate it from the cell membrane the nuclear membrane contains nuclear pores very small openings that allow certain things into and out of that nucleus now at the center at the heart of our nucleus is a region A specialized region known as the nucleis and the nucleis is the region where we synthesize incomplete ribosomes the ribosomes that end up being in this region the endoplasmic reticulum or as free ribosomes found inside the cytool which we'll talk about in just a moment so let's move on to this region here so we have the cell membrane this is our nucleus the nuclear envelope that contains those nuclear pores as well as our DNA that is found inside the nucleus and this is our region known as the nucleolus now let's move on to region number four and region number five together these two regions are known as the endoplasmic reticulum now just outside the nucleus are a series of mazike membranes called the endoplasmic reticulum or simply the ER and we have two types we have the rough endoplasmic reticulum that contains these dots and this smooth endoplasmic reticulum shown in region five that lacks those dots so the endoplasmic reticulum right next to our nucleus contains ribosomes embedded in our membrane of that ER and this gives it a granular appearance under the microscope and that's exactly why we call it the rough ER because it contains those ribosomes inside the membrane of the ER now what exactly is the function the purpose of our ER so basically the ER the rough endoplasmic reticulum functions to synthesize our proteins it synthesizes the proteins that end up either being secreted from the cell or and up in the cell membrane of our cell so basically we see that the nuclear envelope and the membrane of our ER are jointed they're connected in these regions and that's exactly why once our nucleis synthesizes those incomplete ribosomes those ribosomes can then be placed inside this ER to basically embed the ribosomes inside the m MBR of the ER and then those ribosomes can synthesize our proteins now what about this section the smooth ER shown by region five this region also contains these membranes but they do not contain ribosomes and so that means this smooth ER isn't directly involved in synthesizes proteins instead the smooth ER functions to produce lipids our fats as well as to detoxify toxins and drugs now the next section we're going to examine is region number six this is known as the GOI apparatus the GOI complex or simply the GOI it's named after the scientists who came up who first noticed this type of structure within our cell so basically what happens is once our proteins are synthesized within our ER then they travel into the GOI apparatus and the GOI apparatus is a series of membrane bound sacks that functions as packaging and sorting center of our cell it packages sorts as well as modifies proteins before they're actually secreted by that cell now proteins that leave our G apparatus once they are modified leave in little sections little structures known as secretory vesicles and these are shown by these blue vesicles here so once our protein is modified for example we add some type of sugar onto the protein it leaves the GGI apparatus inside of vesicle and the reason it stays inside the vesicle is to protect the structure of our protein so that vesicle can then basically go onto the membrane and the protein can either remain in the membrane of the cell or it can secrete itself outside that cell now we also have ribosomes that are actually attached to the membrane of our endoplasmic reticulum and these ribosomes are known as free ribosomes they are shown in this region these two regions are our free ribosomes so ribosomes are not organel because they do not have any type of membrane these ribosomes are simply structures so ribosomes that are found in the cytool which is region number 14 it's this clear region shown on the entire cell so we have ribosomes that are found in the cytool and which are not bound to any type of membrane are called free ribosomes and they function to also synthesized protein but these proteins synthesized by the free ribosomes end up stain within our cytool so that's the main difference between the ribosomes found inside the rough and the plasmic reticulum and the free ribosomes the ribosomes in the ER basically create proteins that either leave that cell or end up being in the cell membrane however the proteins created by the free ribosomes stay in the cytool now what exactly is the difference between cytool and cytoplasm because the two are sometimes confusing or confused basically the cytoplasm is the region between the cell membrane and the nucleus and the cytoplasm includes all the organel and all the structures found between these two sections so that includes the mitochondria which we'll discuss next that includes the ribosomes the gold je apparatus the vesicles our erer and everything else in between the cell membrane and the nucleus now the cytool is not exactly the cytoplasm the cytool is basically the cytoplasm minus all the structures and organel so if we take out all the organel between the cell membrane and the nucleus we are simply left with the fluid region and the fluid is known as the cytool and the cytool contains these free ribosomes that basically move about this entire fluid region now let's move on to the mitochondria the mitochondria is a very important structure in the eukariotic cell the mitochondria in a way is like the nuclear parlant because it transforms one type of energy into a different type of energy that the cell can then use to help power different types of processes so the mitochondria is the power plant of the cell it breaks down molecules biomolecules and produces energy that can be harvested to power many different processes now we'll discuss the details of the mitochondria organ now in a different lecture but here we'll mention that it contains an outer layer as well as an inner membrane layer and it also contains its own DNA and can actually undergo its own process of replication a it can undergo a process known as binary fion and we'll discuss that in more detail in a different leure so this is our mitochondria it's the power plant of our cell now let's move on to our lomes which are described by these two green vesicles here so lomes are essentially specialized vesicles that contain hydrolytic enzymes so that means inside the environment of our lome we have a relatively low PH it's about five and these lomes basically help break down unwan material inside the cell now let's move on to another type of specialized vesicle known as the peroxisome the peroxisome are also known as microbodies so very small bodies that contain that cell membrane and its own internal environment so peroxisomes are specialized vesicles that create hydrogen peroxide so H2O2 that break down fats as well as detoxify dangerous substances especially in the liver found inside our bodies so the cells in the liver of our body contain lots of peroxisomes because we have to break down different types of toxins that we ingest into to our body such as alcohol for example now let's move on to a region known as the centrol the Centrio is basically this region here and the primary function of our centrioles is during cell division so when the cell decides to divide these basically help to separate the cell into two different cells and and finally the last thing we want to discuss is this tail like region here this is known as our flagellum now the flagellum is basically a structure that gives the cell motility it gives the cell the ability to basically move now both procaryotes and ukar have their own type of fugel that moves in its own way and and is composed of its own type of protein we'll discuss that that when we focus on the fella in a different lecture now some other things that we should probably mention are glycosomes which is another type of microb body so plant cells also contain microbodies known as glycosomes and the glycosomes also help to break down our lipids into some typ of usable form of energy such as sugar so the two types of microbodies are peroxisomes which are found mostly in animal cells and L and uh glycosomes which are found most mostly in plant cells now by the way centrioles are only found in animal cells they are not found in plant cells and one other thing one other organel that plant cells have and animal cells do not have is the chloroplast the chloroplast is basically the organel that uses oxygen uh and some type of carbon source so CO2 and oxygen or actually no if you uses CO2 and water to create sugar molecules and it releases oxygen into the atmosphere that's the oxygen that we basically breathe in so we can imagine that if our mitochondria is the nuclear power plant the chloroplast is our solar power plant it uses the energy that comes from sunlight and it combines carbon dioxide and water to form sugar molecules usually starch so basically these are the different types of organel and structures that are found inside eukaryotic cells and in the next series of lectures we're going to discuss each one of these organel in detail