肌肉收縮实验英文实验报告.docxVIP

2014年春季学期 机能实验学实验报告日期：2014/5/20题 目The Nature of Muscle Contraction成绩实验者年级专业Aim To learn the preparation of the sciatica nerve calves .To investigate the relationship between muscle contraction and the frequency and the strength of the nervous impulse by observing the shrink shape of skeletal muscle . To understand the concept of threshold stimulus ,subliminal stimulus ,supraliminal stimulus .Animals and equipment Toad .1 frogs surgical equipmeng ,1 thorn frog needle ,1 zinc-copper arch ,1 grass needle ,1 all-purpose holder ,ringer solution ,experience system for medical calculation ,tonotrans ducer.Methods and stepsprepare the sciatica nerve calves .destroy the myelencephalon wipe out the upside and the visceral of the body Peel off the skin Free sciatica nerve Make the specimen of the sciatica nerve calvesCheck out the specimen .The Nature of Muscle Contractionequip the experimental apparatus as the picture show .to investigate the influence of stimulus strength to muscle contraction .to research the single twitch and maximum twitch .consequence the acquiration of threshold and the most suitable stimulus intensity Chart 1 With the 10.00ms waviness width and the pattern “single twitch”,choose 0.04V strength to experiment ,muscle did not shrink .Choose 0.05V strenth,muscle shrink .(see chart 1) So we estimate the threshold is 0.05V.Chart 2 As the chart 2 shows ,the waveform in the strength of 0.7V is higher than it in both 0.6V and 0.8V. So we estimate the most suitable intensity is 0.7V.the observation of the composite contraction Chart 3The chart 3 shows the waveform of incomplete tetanus .It shows that with high frequency stimulus,muscle shrink may create larger tension in a short time to make a summation .Chart 4From the chart 4，we can discover ,the excitment of muscle can’t sum totally ,but the shrink can . It also shows that the excitment is anterior ,shrink posterior .Discussion attention :Add ringer solution frequently to keep the vigour of the specimen .Tur