Page 14 - model 1

• The shortage of ATP in the muscle leads to prevent the separation of the transverse
links from the actin filaments, so the muscle still in the case of contraction and can’t

relax that causing painful muscle spasm.

• At rest the muscle supplied by enough amount of oxygen to perform aerobic cellular
respiration, which produces a large amount of ATP causing that separate the transverse
links from the actin filaments and the muscle go on alternation of contraction and

relaxation.

• The excessive spasm may leads to tear the muscle causing bleeding, also the muscle
spasm may be caused due to the troubles that resulted from the arrival of incorrect

nerve impulses from the brain to the muscles during its normal performance.

20 Biology General Secondary Certificate 2019 - 2020 2017 - 2018 Shorouk Press