運動素乃是生物體內一種水溶性酵素蛋白質分子，它像一台小火車似的，以生物體中的微管做為其前進軌道，做單方向性前進負責運送胞器、染色體等重要物質。它與核酸鍵結，進而引起其結構的變化，來產生運動機制。
　　本文以運動素為探討對象，首先建立數學量化的運動模型，並且以運動素處於外加負載下，探討兩種不同運動行為模式。並用速度、停滯時間、平均距離、隨機性等四種參數解釋其運動機制，並且與文獻實驗數據做比較，呈現相同的趨勢。
　　結果顯示，當運動素在固定濃度下時，其速度隨著負載的增加而縮小，並且在達到6pN時會停止前進。本文同時說明thermal rachet和power stroke的差異性，結果顯示兩者之整體速度有接近的趨勢，這可用來說明此兩種模型皆有其準確性。

　　In the paper, kinesin is a water enzyme protein molecular. It move on the microtubule as a small train in cell , speeds one-way to carry important material ,for example organelle and chromosome. Binding invoke the changing of structure bring the system of movement.
　　The kinesin be analyzed under the kinetic model of mathematic two kinds of differ moving behavior when kinesin is base load. In the condition, moving mechanicity is explained by four parameters : velocity、dwell time、the mean distance、randomness, and it compare with experiment data to show the same trend.
　　The result showed when the concentration of kinesin is constant , the velocity decreased with increase of base load, and 6pN stop to go forward. We explained the different of thermal rachet and power stroke. The result presented that the velocity of thermal rachet and power stroke show close to each other , therefore, it is to explain that two model have its correctness .

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