Lab 6 Review #1

cardiac muscle's intrinsic contraction rhythm is altered by...

• nervous control

• endocrine control

this type of attachment is more durable, small and common. an example of this would be an aponeurosis:

• direct attachment

• indirect attachment

this protein bisects the H zone to produce a dark line termed the M line..

• actin

• myosin

• tropomyosin

• myomesin

identify the highlighted structure depicted above:

• a band

• i band

• h zone

• z disc

identify the highlighted structure depicted above:

• a band

• h zone

• i band

• z disc

identify the highlighted structure depicted above:

• z disc

• actin (thin filament)

• myosin (thick filament)

• a band

which of the following best describes the "power stroke" phase of cross-bridge formation?

• ATP binds to myosin, and the actin-myosin complex dissociates

• ATP is hydrolyzed, and myosin heads return to resting confromation

• myosin heads bind to actin to form the cross bridge

• myosin heads change conformation, allowing the filaments to slide past each other

which of the following best describes dystrophin's role in muscle contraction?

• connects myofibrils at the Z line

• links thin filaments to the sarcolemma

• binds actin in order to begin cross-bridge formation

• forms perpendicular cross channels called terminal cisterns

which of the following occurs at the stage labeled "2"?

• depolarization is caused by sodium ions flowing into the cell

• depolarization is caused by sodium ions flowing out of the cell

• repolarization is caused by potassium ions flowing into the cell

• repolarization is caused by potassium ions flowing out of the cell

the biceps curling a barbell would be an example of...

• isometric contraction

• isotonic contraction

• eccentric contraction

• concentric contraction