 hill.com/sites/ x/student_view0/brainpop_movies.html#

 Because of the way we usually see bones, it’s easy to think of them as dry and lifeless.  The fact is they are neither dry nor lifeless  Bones are living organs made of several different tissues.  They are moist, supplied both blood and lymph vessels, as well as nerves, bones are as much organs as are the heart and brain.

 The average human adult has 206 bones.  Bones support and protect parts of the body.  They work with your muscles so you can move.  They help you maintain homeostasis by storing minerals and making blood cells

 Bones are made of connective tissue and minerals.  There are two different kinds of bone tissue:  Compact bone: dense and rigid, does not have open spaces.  Spongy bone: many open spaces, provides most of the strength.  Bones also contain a tissue called marrow, which produces blood cells and stores fat

 When you were born, you didn’t have much true bone.  What you had was cartilage, which is soft and rubbery.  As you grew, most of the cartilage was replaced by bone.  Most bones still have cartilage at the ends.  This cartilage cushions the areas where bones meet (joints)

 A place where two bones meet is called a joint.  Your joints allow you to move when your muscles contract.  Some joints, like those in your skull allow for little or no movement.  Other joints, like those in your shoulder allow for many movements  Joints are held together by ligaments, which are strong bands of connective tissue

 EQ: How do organ systems work together to enable an organism to maintain homeostasis?

 Your skeletal system does not work alone!  Muscles connect to your skeleton and they contract and move the skeleton along (you use over 200 muscles each time you take a step!)

 Muscle is an organ that contracts and expands, creating movement.  In your body there are more than 600 muscles.  Muscles not only help you move, they also give your body shape and produce heat in your body.

 Most of the meat on our bones is muscle.  There is so much of it, it makes up about 40% of our total body weight.  Available in all shapes and sizes, muscles shorten on command, stretch when necessary, and then bounce back to their normal resting strength.

 There are two main groups of muscle, voluntary and involuntary.  Voluntary muscles are muscles your control consciously (you have to think about how and when to move them)  Involuntary muscles are those that work automatically (you don’t have to think about them)

 You have three types of muscle tissue in your body:  Skeletal  Smooth  Cardiac

 These muscles move bones.  They are attached to bones by tendons (thick bands of tissue)  They are voluntary muscles.  They are the most common type of muscle in your body.  They are striated (striped).  They contract and expand quickly.

 Involuntary (work automatically)  Found in the walls of many of your organs, such as your intestines, blood vessels and skin.  They move the organs as needed.  They contract and relax slowly.  They are not striated  They are thin muscles

 Only found in the heart.  It is involuntary  It is striated.  It contracts nonstop all day and night for your entire lifetime!

 Your muscular system is very closely connected to the nervous system.  This makes sense because you usually do not have to think to keep your heart beating, your internal organs working or even before you move.

 What are the organs and functions of the skeletal and muscular systems?  How do the skeletal and muscular systems interact?