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High school biology
Course: High school biology > Unit 8
Lesson 3: The musculoskeletal system- Skeletal structure and function
- Cartilage
- Ligaments, tendons, and joints
- Three types of muscle
- Anatomy of a skeletal muscle cell
- LeBron Asks: What muscles do we use when shooting a basket?
- The musculoskeletal system review
- The musculoskeletal system
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Skeletal structure and function
Skeletons support and protect our bodies. Bugs have exoskeletons outside their bodies, while humans have endoskeletons inside. Our bones are in axial (skull, ribcage, spine) and appendicular (arms, legs) groups. Bone marrow makes blood cells; more specifically, red marrow makes blood and yellow marrow stores fat. Created by Tracy Kim Kovach.
Want to join the conversation?
- is the red and/or yellow bone marrow housed inside of the cancellous bone?(14 votes)
- It depends on age. When you're young all your bone marrow is red marrow, as we age a lot of marrow in our long bones become yellow and mostly fatty. There is still red marrow in flat bones and the epiphysis of long bones.(12 votes)
- why does it pain when our bones break? do they have nerves or anything else, other than bone marrow, going through them?(20 votes)
- though bones may look lifeless, they are constantly growing and active. (growth need not be only in length but also in production of new cells). coming to the point, bones are richly supplied with capillaries and nerves. the capillaries help in blood circulation too.(10 votes)
- Are the scapula and clavicle part of the Appendicular or Axial skeleton?(14 votes)
- Appendicular. Both the scapula and the clavicle are involved with the movement of the arms, so they are associated with the appendicular.(20 votes)
- I was told that when a bone is broken majorly, doctors take a chunk of bone from the pelvic girdle and patch it up. So when this happens, won't the haemopoeisis get disturbed. And will it cause any irregularities in the structure of that bone?(12 votes)
- I've read about rickets which is when your bones start bending. What causes this. i just can't remember what causes rickets.(6 votes)
- So rickets is a bone disorder, then why is it concerned with vitamin D?... now you may intake sufficient calcium and phosphorus but to draw nutrition out of them, your body needs vit D. When that's missing, your body draws calcium from your bones which makes your bones decalcified. This causes rickets. Hope this helps.(9 votes)
- Why do bones really break if we have layers of skin on us?(3 votes)
- If you wrapped a few layers of plastic wrap around a pencil, you could still break the pencil underneath. The skin can help protect the muscle, bone, and other tissues underneath it, but only to a certain point.(14 votes)
- is the shoulder bone part of the appendicular or axial skeleton?because in my science book the shoulder bone is a part of appendicular skeleton but i am not sure.(4 votes)
- The scapula and clavicle are part of the appendicular skeleton.(9 votes)
- so what is the sholder bone called(5 votes)
- The shoulder is the joint between the humerus, which is the long bone in the upper arm, and the scapula, which is commonly called the shoulderblade.(6 votes)
- What's the differnce between hip and pelvis?(4 votes)
- The hip is usually what we refer to the joint in that area, and the pelvis is the hip-bone. Most people will just assume you're talking about the area in general though.(7 votes)
- so basically what is the main function of the skull(2 votes)
- If I had to name the one most important function of the skull, it'd be how the cranial bones make a hard, protective shell around the brain.
It has other jobs, though. The orbits support and protect your eyes so that you can see. Cavities in the temoral bone are essential for hearing and balance. The mandible and maxilla are useful for eating, drinking, and talking. Muscles can attach to the bones of the skull, letting you move your head, move your jaw, move your eyes, and have facial expressions. The structure of the nasal cavity protects your respiratory system and helps stop you dehydrating through your lungs. Because the skull is made of bone, it helps with maintaining levels of calcium and phosphate in blood.
So, almost everything you can do with your head depends on the structure of the skull in some way. And still, I think its most important job is to protect the brain.(9 votes)
Video transcript
So in this video we're going to be
talking about 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 cancellous bone 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 hematopoiesis. And speaking of hematopoiesi,
where exactly does this Hematopoiesis 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 hematopoiesis, which makes sense because the red blood cells
from hematopoiesis actually make red bone marrow look red to the naked eye so you can remember that red bone
marrows for blood or hematopoiesis 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