Worksheetsmuscle contraction
Total questions: 10
Worksheet time: 50mins
The sarcolemma is:
a material that fills up the space inside a muscle cell
the membrane that surrounds a muscle fiber
the smallest unit of a myofibril
the organelle that makes up a muscle fiber
The sarcoplasm is:
a material that fills up the space inside a muscle cell
the membrane that surrounds a muscle fiber
the smallest unit of a myofibril
the organelle that makes up a muscle fiber
T-tubules help by providing
a source of Calcium
a source of ATP
a passageway into deeper portions of a muscle cell
a receptor site for the myosin heads to bind to
Myofibrils are the main _____________ of a muscle cell.
organelle
structural protein
control center
energy source
Which of these proteins are found in a sarcomere?
Titin
Actin
Myosin
Acetylcholine
Motor units for precise movements have __________ muscle cells than for gross body movement motor units, like picking up a bag.
more
fewer
larger
smaller
Calcium's purpose in muscle contraction is to
cross the neuromuscular junction and stimulate the sarcolemma
travel down the T-tubule to reach interior myofibrils
bind to troponin, move tropomyosin, and expose actin's binding sites
attach to actin, forming a crossbridge
The muscle cell is able to relax when
the cell runs out of ATP
Calcium is absorbed back into the sarcoplasmic reticulum
the z-lines in the sarcomere are as far apart as possible
ATP allows myosin to release its hold on actin
The contracting unit of a muscle is the _______________.
sarcomere
myofibril
muscle fiber
muscle cell
Chemical inputs necessary for muscle contraction include:
acetylcholine
calcium ions
ATP
oxygen
