Muscle System Flashcards
function of the muscle cells (3)
can contract and expand to make body parts move
1. move skeletal system
2. move blood through heart and blood vessels
3. move food through digestive system
peristalsis
the movement of food through the digestive system
slow and rhythmic contractions and relaxations of smooth (visceral) muscle tissue
What are the only cells that have the ability to expand and contract?
muscle cells
What percent of human male body weight is muscle tissue?
60%
What percent of female body weight is muscle tissue?
40%
How many skeletal muscles are in the human body?
600
Where is skeletal muscle tissue found?
along the bones of the body
tendon
attaches muslce to bones
How long can skeletal muscles be?
1.5 inches long
What kind of cells can be multinucleated (have more than one nucleus)?
skeletal muscles
Straited cells
contain large amounts of protein
contain bands called myosin and actin
Are skeletal muscles voluntary or involuntary
Voluntary
voluntary movement
contractions and relaxations caused by a conscious effort
What kind of cells appear as neatly stacked pipes?
skeletal muscle cells
function of skeletal muscle cells
to pull on tendons attached to bones to make the skeletal system move
What kind of muscle work in pairs?
skeletal muscle
fiber
a muscle cell
All-or-None Law
when stimulated a muscle cell will contract completely or not at all
How is skeletal muscle strength determined?
By how many muscles are “told” to contract at a given time
Lactic Acid
Waste product of skeletal muscle cells’ contractions and relaxations
diffuses to the bloodstream and is taken to the liver
What does the liver do to lactic acid?
converts it to glycogen (a stored form of glucose - sugar)
Where is cardiac muscle tissue found?
only in the heart- especially the ventricles (lower pumping chambers)
Are cardiac muscle tissues multi-nucleated (have more than one nucleus)?
Some are
how do heart muscles move
they contract and relax rhythmically
Are heart muscles striated?
Yes, but not as much as skeletal muscle cells
What kind of cells are branched?
cardiac muscle cells
Where are disks present?
cardiac muscle cells
Unique characteristic of heart muscle cells
able to contract and relax without being stimulated by a nerve-borne impulse
visceral muscle tissue
smooth
Is visceral muscle tissue voluntary or involuntary?
Involuntary
Is visceral muscle tissue striated?
very, very few striations
Is visceral muscle tissue multi-nucleated?
No - one one nucleus per cell
Where can you find visceral muscle tissue?
walls of arteries and veins (make blood flow)
walls of digestive organs (allow food to be churned and passed along) - peristalsis
