Muscles Flashcards
How many muscle groups are there?
600
What type of pairs are muscles grouped into?
antagonistic pairs
What is the meaning of antagonistic pairs?
One muscle moves in one direction and the other in another direction.
What part of the muscle is stationary and attached to the bone?
Origin
What part of the muscle attaches to the bone across a joint
Insertion
Where are the origins and insertions of muscles?
On opposing ends of a muscle
The origin is closer to what area of the body compared to the insertion?
the body midline
What happens to the insertion and origin in contraction?
The insertion gets pulled toward the origin
Another word for “single muscle” is…
Whole muscle
Word for muscle bundle
Fascicle
The Fascicle is surrounded by…
Fascia
An elastic type substance that surrounds and individuates all of the fascicles
Fascia
Fascia and fascicles all come together to form….
Tendon
Another word for muscle cell
muscle fibre
Muscle cells contain long cylindrical structures called:
myofibrils
How many nuclei do muscle cells have?
thousands (multi nucleate)
What kind of element is a part of a myofibril?
contractile
What does it mean when it’s said that muscle is striated?
The alternating pattern of dark and light bands on muscle
The area between the striations on muscle is…
the contractile portion of muscle
The unit of contraction of muscles is referred to as a…
sarcomere
The dark lines that define the borders of a sarcomere are called..
Z lines
The two types of protein filaments in sarcomeres are called
Actin and Myosin
The darker portion of the sarcomere with mostly myosin is called
A band
Dense protein section of sarcomere with overlapping actin
A band
What is the H zone?
the small strop in between where actin extends t where ther is no actin, just myosin
What is the M line?
defines the centre portion of the sarcomere
the lighter portion of the sarcomere with Actin and contacts z line
I band
Muscle contraction results from …
slight shortening of each sarcomere
Activation of skeletal muscle depends on what type of activation?
neural
Name of junction where nervous system communicates with the muscles
neuromuscular junction
What neurotransmitter do muscles release?
ACH (acetylcholine)
the neurtransmitter that acts on muscles to start contraction process
ACH
Motor neurons release ACh leads to waves of electrical activity, called:
depolarization
When depolarization spreads deeper into the muscle, what does it travel through?
T tubules
All electrical activity in muscles has the effect of releasing what from the sarcoplasmic reticulum?
calcium
The calcium store house in the muscle
sarcoplasmic reticulum
the presence of calcium being released from muscles causes interaction of…
actin and myosin fibres
What is the sliding filament mechanism?
when actin and myosin slide closer to eachother
When are myosin heads attached to the actin?
when activated into power stroke
What does the power stroke do?
pulls myosin toward the centre of the sarcomere
The actin have rope-like structures across the surface which have two different names:
Troponin and tropomyosin
the shape of troponin is
discs
the shape of tropomyosin is…
rope
What do troponin and tropomyosin do?
They block the myosin heads from binding to the sites on the actin when calcium is not present
For muscle relaxation, ATP is needed for…
Ca2+ transport into the sacroplasmic reticulum and to bind to myosin to get it to detach from actin
The energy require for muscle contraction is required to do what?
to reset the process of binding
the cycle of contractile process shows what?
how energy goes into the system
Simple 4 step process of contractile cycle
- ATP binding on the myosin head to release
- Conversion to ADP
- Reset of myosin head
- Ready for another power stroke
Why do dead bodies become rigid?
because the organism has stopped making ATP, meaning myosin heads can’t unbind from actin
free floating ATP in muscle cells allows for how many seconds of contraction?
10 seconds
Creatine phosphate allows how many seconds of contraciton?
30-40 seconds
Creatine phosphase can transfer a phosphate group to …
ADP
Energy from glucose can produce…
ATP
Using stored glycogen for muscle energy consumption depends on the presence of what?
oxygen
The burning sensation from lifting a heavy load is from…
the production of lactic acid
Long term solution to muscle energy consumption is…
aerobic metabolism
the delay after activity has ceased where heart rate and breathg remains elevated for a periof of time to replenish all of ATP stores
Oxygen debt
What is muscle fatigue?
not being able to continue intense activity, which is a result of decreased ATP
Type of muscle that contracts and breaks down ATP slowly
slow twitch
Type of muscle that will produce ATP as needed
slow twitch
type of muscle with a red appearance from many mitochondria
slow twitch
Slow twitch muscles have a high concentration of…
myoglobin
the type of muscles that are involved in standing posture
slow twitch
types of muscles that contract and break down ATP quickly
Fast twitch
Fast twitch muscles have large amounts of…
glycogen and creatine phosphate
What types of muscles use more anaerobic forms of metabolism?
fast twitch
What type of muscles to runners typically have higher amounts of?
slow twitch
What type of muscles do weight lifters typically have more of?
fast twitch
Muscle soreness comes from
damaged sacromeres that produce inflammation and swelling
the type of muscle growth that comes from weight training
hypertrophy
the type of muscle growth that comes from endurance training
hyperplasia
hypertrophy increases the size of…
muscles
hyperplasia increases the number of…
cells in muscles
Aerobic training increases…
blood flow, mitochondria and efficiency of O2 transfer during respiration
Muscular dystrophy is the genetic deficit of…
dystrophin
What is dystrophin important for?
the removal of Ca2+
Excess Ca2+ in cells can cause…
damage and death
the life expectancy of people with muscular dystrophy is…
~30 years
Another word for tetanus disorder
lockjaw
What is tetanus?
a bacterial inflection the causes constant activation of muscles
