In the myofibril cross section shown below, letter B labels __________ .
1
2.
When doing a bicep curl, as you pull the weight in your hand up toward your shoulders, the Bicep acts as....
2
3.
Put the following steps in order:
Actin binding sites are free
A cross bridge is formed
Calcium binds to troponin
Troponin changes shape
Tropomyosin shifts
2
4.
Once a cross bridge is formed, a powerstroke takes place in which _____________________and ______________.
1
5.
"A few hours after a person or animal dies, the joints of the body stiffen and become locked in place. This stiffening is called rigor mortis. It's only a temporary condition. Depending on body temperature and other conditions, rigor mortis lasts approximately 72 hours. The phenomenon is caused by the skeletal muscles partially contracting. The muscles are unable to relax, so the joints become fixed in place."
After a person is dead, their cells no longer produce the energy form needed to break a cross bridge, so the actin and myosin stay contracted producing tone. Which of the following is unable to happen in a person once dead, to break the cross bridge, causing this condition?
2
6.
Calcium released from the _________ binds to troponin which changes shape to shift letter _________.
1
7.
In the myofibril cross section shown below, letter A labels a sarcomere, the contracting unit of a muscle. Letter A extends from letter D to letter D. Letter D labels.....
1
8.
Which of the following occurs during muscle relaxation? (in other words which does NOT happen during muscle contraction?)
4
9.
Please explain EVERYTHING happening in the image in as much DETAIL as possible and using as many vocabulary words as possible.
