 Are you scared by this image? Be comforted by the fact that the skeleton not only provides rigidity and structure to our body, it's essential for the protection of vital organs like the lungs, the heart and most importantly the brain. So the skeleton is a vast structure and in order to make it easier to study what we do is we break it down into two different parts. So over here the part that you see in white. That part is called axial skeleton. Axial stands for axis so this is the central axis of the body and the axial skeleton is present very close to the axis hence the name. Now the brown part the rest of the skeleton all these parts they are called appendicular skeleton. Why appendicular? Because our hands and legs these are appendages. So appendages are things that are attached to the main body and these appendicular skeletons provide support to our appendages hence they are called appendicular skeleton. So in this video we will look at different parts of the axial skeleton and what bones make it up. So let's go to this part first our skull. So these are two views of our skull and the one in red this part is made up of cranial bones. All these cranial bones they cover the entire head and they are also present inside the eye sockets. And what about the blue part? These bones the blue bones are called facial bones because as you can see they make up the face. Now other than the cranial bones and the facial bones the skull has a few more bones. Six of them are present inside the ear so this is our external ear and if you go inside here is the middle ear and here are the ear ossicles so we call them ear ossicles. These are nothing but small bones so they are really really small as you can see. So what are these bones called? You might have studied them in a lower grade. This bone right here is called the malleus. It's a hammer shaped bone and the next bone this one right here it's called the incus. An anvil shaped bone and the last one is a stirrup shaped bone and is called the stay piece. The last bone that we are going to talk about in the skull is a bit weird so as you can see it is present below the jaw and in front of the throat so it's called the hyoid and as you can see it seems to be hanging in the air so that's not done by any other bone they are connected to some or the other bone but this one is not then how does it stay in place how does it not fall down that's because even though it's not connected to any bone it is connected to muscles and it helps in other movement of the tongue the movement of the throat etc so that's what we have in the skull the cranial bones the facial bones the ear ossicles and the hyoid now let's move over to the vertebral column so the vertebral column I'm sure you know it's our backbone it's present in the back of course and the vertebral column is made up of these small units called the vertebrae and there are different kinds of vertebrae depending on the level at which they are found so the vertebrae at the level of the neck these are called the cervical vertebrae cervical in Latin means neck hence the name this portion this entire portion is the chest region and these vertebrae are called thoracic vertebrae thorax means chest so there are seven cervical vertebrae 12 thoracic vertebrae and then in this region the lower back we have five vertebrae which are called the lumbar vertebrae there are five in number and lumbar relates to loin so loin is lower abdomen region so that's what the lumbar vertebrae support that's why they call the lumbar vertebrae and below the lumbar vertebrae we have this white bone and this is the sacrum there is just one vertebrae it's the sacrum in other animals and in our ancestors they used to be separate vertebrae but in us all the separate vertebrae have fused have joined to form one single vertebra sacrum which forms the base of our vertebral column and the last vertebrae is the coccyx and you might have heard it is also the tail bone it's also one in number again like in other animals there are coxigial vertebrae there are a few coxigial vertebrae separate ones but in us they have all been fused together to form one bone and what does it do in us it has absolutely no function we do not have a tail so in us it's a vestigial organ so this is all about the vertebrae now the thoracic vertebrae they are as you can see in this picture connected to the ribs they come to the ribs so there are 12 ribs on each side and each of the ribs are connected to the thoracic vertebrae at the back so 12 thoracic vertebrae 12 ribs and at the front they are connected to this bone which is called the sternum so depending on how they're connected to the sternum the ribs have different names because first let me name let me label the sternum bone this is the sternum the first seven ribs they are directly connected to the sternum through cartilage of course so these white things they are not the ribs themselves they are cartilage but all of these seven ribs they are connected separately to the sternum all of these ribs they are separate from each other and they are connected to the sternum and are called true ribs why we will see in a second the next three ribs this this and this eighth ninth and tenth ribs they are not directly connected to the sternum instead if you notice they are connected to this cartilage of the seventh rib all of these ribs eight nine and ten they are connected to their own cartilage which join and they in turn join to the cartilage of the seventh rib which finally connects to the sternum so these three ribs are not directly connected to the sternum but through the cartilage of the seventh rib hence they are called false ribs that doesn't mean the ribs don't carry out their function they are ribs it's just a nomenclature that we follow for our own understanding and the last two ribs as you can see these two ribs they do not have any cartilage of their own at all so the 11th and 12th ribs they don't have any cartilage they are not connected to the sternum so they are not connected to the sternum and are called floating ribs they seem to float hence are called floating ribs so to summarize we have seen that the axial skeleton is made up of the skull which has the cranial bones which covers the head then the facial bones which covers the face then there are the ear ossicles in the middle ear and the hyoid below the jaw in front of the throat and then there are the vertebrae in the vertebral column neck region cervical vertebrae chest region thoracic vertebrae lower back region lumbar vertebrae base of the vertical column sacrum and the tailbone the coccyx and then there is the sternum in the front and then there are these 12 ribs the first seven ribs are the true ribs the eighth ninth and 10th ribs are the false ribs and the last two ribs are the floating ribs and together the sternum the ribs and the vertebrae they form the rib cage inside which are housed the lungs and the heart