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When a muscle contracts it will pull the

Force transducer

The y-axis of a myogram represents

Muscle tension (or force of contraction). Electrical activity of motor units

Between lag and contraction is when what occurs

cross bridge formation

During contraction what phase of cross bridging are we in

Power stroke

During relaxation phase what cross bridge formation is happening during a twitch

Hydrolyzing ATO

One motor neuron can cause contraction of

1,000 muscle fibers

If you activate a small motor unit (view it electrically)

You’ll measure a single motor unit shown as a small spike on the graph

The muscular muscular junctions, the more fibers the greater the

Spoke from that motor unit

When a motor neuron controls a 1000 fibers you’ll get a

Big spike in electromyography

Your not measuring force of a thousand fibers controlled by the neuron your measure the

Summation of electrical activity of all those 1000 fibers.

You turn off what first

Large motor units, large intermediate fibers, median electric intermediate fibers, and then small motor units. Then everything would be turned off.

A twitch takes how long

20 milliseconds or 200 for example or 50th of a second or 5th of a second. It varies.

the neuron determines rhe

Intensity by frequency of action potentials (not by amplitude of acts of action potential)

Action potentials can get close to one another but they cannot

Stand on one another. The can never summit.

Action potentials can’t summit but the twitch they produce

Can . There’s a limit to the frequency of action potentials.

Muscles must have an enormous amount of

ATP- dedicated to driving crossbridge cycles

Do muscles cells store ATP

No they don’t

How do muscles get atp if they don’t store it?

Muscles work harder and harder depending on what your doing, so they’ll make ATP as fast as they need it.

When your sprinting you need more

ATP

When you get up an start moving what enzyme is activated when ATP does down

Adenylate kinase enzyme will sense this, (atp is converted to adp) and it will take off a phosphate off ADP to make another AMP

When your at rest your

Building a creating phosphate pool. Creatine kinase will take phosphate off ATP and result in formation of ADP