The protein named kinesin is the main motor in muscles that causes them to move
ID: 1794846 • Letter: T
Question
The protein named kinesin is the main motor in muscles that causes them to move and exert forces. Kinesin walks along tubes called microtubules. Kinesin has been measured to take 8nm steps when pulling a cargo with a load of 6.5pN. (a) How much work does kinesin do on the load in each step? (b) ATP is the source of chemical energy in muscle cells. Kinesin consumes ATP as it moves. One molecule of ATP contains 0.36eV of useful energy. About how many ATP molecules does kinesin consume for each step it takes?
Explanation / Answer
a)
F = force = weight = 6.5 x 10-12 N
d = distance travelled = 8 nm = 8 x 10-9 m
work done is given as
W = F d = (6.5 x 10-12) (8 x 10-9) = 5.2 x 10-20 J
b)
E = energy by one molecule = 0.36 eV = 0.36 x 1.6 x 10-19 J
n = number of molecules = W/E = (5.2 x 10-20)/(0.36 x 1.6 x 10-19) = 0.903
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.