muscle fibers

the long, slender cells that make up muscles

striated muscle

a muscle that is connected at either or both ends to a bone and so move parts of the skeleton

voluntary muscle

a muscle that is under conscious control


Connective tissue surrounding a fascicle


A discrete bundle of muscle cells


Connective tissue surrounding a muscle fiber


tissue that connects muscle to bone


broad, fibrous sheets of connective tissue

smooth muscle

a muscle that contracts without conscious control and found in walls of internal organs such as stomach and intestine and bladder and blood vessels (excluding the heart)

cardiac muscle

the muscle tissue of the heart

muscular system

enables movement of the body and internal organs


an extensible membrane enclosing the contractile substance of a muscle fiber


Micorsopic, fiber-like structures that occupy most cytoplasm in skeletal muscle cells

light bands

only actin

dark bands

both actin and myosin


The smallest functional unit of muscle tissue


AKA thick filaments, A Protein that makes up nearly half of the proteins in muscle cells


AKA thin filaments, A globular protein that links into chains, two of which twist helically about each other, forming microfilaments in muscle and other contractile elements in cells.

cross bridges

are formed when tail of myosin molecule, which consists of 2 intertwined helical polypeptide heavy chains, contract and link the thick and thin filaments together; the gobular heads, are business end of myosin;

sarcoplasmic reticulum

corresponds to endoplasmic reticulum, network of membranous channels that surround each myofibril and runs parallel to it

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording