muscle contraction Flashcards
(34 cards)
three types of muscle
smooth
cardiac
skeletal
smooth muscle
contracts without conscious control
cardiac muscle
contracts without conscious control but only found in the heart
skeletal muscle
type of muscle you use to move
role of skeletal muscle
pairs of skeletal muscles contract and relax to move bones at a joint
- act as levers as they are incompressible
what are muscles working together to move a bone called
anatagonistic pairs
what is the contracting muscle
agonist
what is the relaxing muscle
anatagonist
what is the cell membrane of the muscle fibres
sarcolemma
muscle cells cytoplasm
sarcoplasm
what do t tububles do
spread electrical impulses throughout the sarcoplasm so they reach all parts of the muscle fibre
what is the sarcoplasmic reticulum
network of internal membranes that run through the sarcoplasm
sarcopladmic reticukum role
stores and releases calcium ions that are needed for muscle contraction
what are myofibrils
made up of proteins and are highly specialised for contraction
- organelles
what are thick myofilaments made of
myosin
what are the thin myofilamnets
actin
what do dark bands contain / A BANDS
thick myosin filaments with some overlapping thin actin filaments
what do i bands contain
only thing actin filaments
what is a z line
whole sarconere
what is a sarcomere
short unit myofribtils are made up of
m line
middle of each sarconere
- middle of myosin filaments
h zone
only has myosin filaments
what happens at the m like and h zone
myosin and actin slide over eachother to make the sarcomere contract > myofibrils and muscle fibres contract > sarcomere returns to their original length
