skeletal structure and then the function of those skeletons and specifically

human skeletons is what we're interested in

but before we talk about human skeletons let's talk about bug skeletons or the

skeletons of arthropods are insects

and so I'm going to draw a little ladybug here and our little ladybug

being an arthropod has what is called an exoskeleton and the XO and XO skeleton

actually first the fact that this skeleton is outside of the ladybug

so "exo" is actually Greek for outside or external humans on the other hand we are

vertebrates and as vertebrates we have this amazing network of bones located on

the interior of our bodies and so we have what are called endo skeletons and

endo is greek for within or inner referring to the location of the

skeleton is being inside of our bodies as opposed to outside now as humans our

endoskeleton performs a variety of pretty vital functions

the first of which is it supports our body and provides a framework for

movement

so what does this mean are our body is supported by the network of our bones

which allows us to sit up and stand and provide some sort of structure for our

body and then the limbs of our body in particular and various joints in our

body provide a framework for movement that allows you to run around to kick a

soccer ball to type on a keyboard

another important function of our skeleton is that it protects our most

vital organs

so if you look at the skull for example it houses our brain and the ribcage it

protects our heart and lungs and other organs and the third function of our

skeleton is

is that it performs a variety of physiological roles in our body namely

the storage of calcium and what is called hematopoeisis, which is the

production of all the cellular components within our blood

so our blood is made up of many different components plasma proteins

among other things and the cellular components of our blood which are red

blood cells white blood cells and platelets are all formed within the bone

marrow of my bones and so those are the main functions of the bones that form

our skeleton

now one way of classifying bones is differentiating between those that form

the axial skeleton and then those that form the appendicular skeleton

now the axial skeleton is made up of our skull and ribcage and our vertebral

column that is the axial skeleton it forms sort of the axis of our body right

right in the center down the midline and then the bones of the forelimbs and our

pelvis form what is called the appendicular skeleton and so

go are four appendages form the appendicular skeleton which is attached

to our central or axial skeleton another classification system for the bones in

our skeleton is the difference between flat bones and long bones

now what are flat bones some examples of flat bones are the bones that make up

your skull

the different bones that make up your ribs and then also the bones in your

pelvis and so flat bones really are describing the shape of the bone

these bones are made up of an inner spongy or cancel a spoon and then the

outer shell is made up of compact bone

there's an inner spongy cancellous bone in an outer shell of compact bone and

flat bone serve primarily to protect our organs and serve as a site for him at 0

police's now long bones on the other hand some examples of those would be the

humerus in your upper arm or say the femur and your lower leg and if I draw a

long bone out here

there are a few different terms to be familiar with when you're referring to

different parts of the long bone the long middle portion of a long bone is

called the diathesis and then the end of a long bone is called the APIs and there

is the small area of bone in between the two are in the middle of the diathesis

and the purposes is called the metaphysis and the metathesis contains

the growth plate which is present

in the long bones of children and these long bones are made up of the same inner

spongy cancellous bone with an outer shell of compact bone just like flat

bones and these long bones really are the ones that provide a framework for

movement like we talked about before and they also serve as a side of him a dope

alesis and speaking of hematopoiesis where exactly does this matter pieces

occur

I mentioned that it occurs in bone marrow which is contained within bones

and there are two different types of bone marrow

there is what is called red bone marrow and then yellow bone marrow

now red bone marrow serves as the primary site for Hamato police's which

makes sense because the red blood cells from matter . says actually make red

bone marrow look red to the naked eye

so you can remember that red bone marrows for blood or a matter of polices

and you can typically find red bone marrow within flat bones and then in the

epiphyses of long bones and then yellow bone marrow on the other hand is

primarily a site for fat storage made up of fat cells called adipocytes and

generally you can find yellow bone marrow within the diocese of long bones