Question

The basis of muscle action is the power stroke of Part A the myosin protein pulling on an actin filament. It takes the energy of one molecule of ATP. 5.1×10−20 J, to produce a displacement of What is the efficiency? 18 nm against a force of 1.0pN. Express your answer as a percentage.

Answer 1

The efficiency of the muscle contraction, which is the power stroke of myosin pulling on an actin filament, can be calculated using the formula Efficiency = (Useful work / Total energy input) * 100%. In this case, the useful work is the displacement of 18 nm and the total energy input is the energy of one molecule of ATP. The efficiency is approximately 3.53 x 10^-8 %.

Step-by-step explanation:

The power stroke of the myosin protein pulling on an actin filament is the basis of muscle action. This action requires the energy of one molecule of ATP, which produces a displacement of 18 nm against a force of 1.0 pN.

To calculate the efficiency, we can use the formula: Efficiency = (Useful work / Total energy input) * 100%. In this case, the useful work is the displacement of 18 nm, which is equal to 18 x 10-9 m. The total energy input is the energy of one molecule of ATP, which is 5.1 x 10-20 J. Plugging in these values into the formula:

1. Useful work = 18 x 10-9 m
2. Total energy input = 5.1 x 10-20 J
3. Efficiency = (18 x 10-9 m / 5.1 x 10-20 J) * 100%

Efficiency ≈ 3.53 x 10-8 %

Therefore, the efficiency is approximately 3.53 x 10-8 %.

Answer 2

The efficiency of the power stroke in muscle contraction, where the myosin protein pulls on an actin filament, is calculated to be 35.3%.

Step-by-step explanation:

The power stroke is a critical phase of the muscle contraction cycle, where the myosin head pulls on the actin filament. This process uses the energy of one molecule of ATP, which equals 5.1×10⁻²⁰ J, to produce a displacement of 18 nm against a force of 1.0 pN. To calculate the efficiency, we use the formula:

Efficiency = (work output / energy input) × 100%

The work output can be calculated by multiplying the force by displacement. So, the work done (W) is 1.0 pN × 18 nm = 18 pN·nm. Since 1 pN·nm equals 1×10⁻²ⁱ⁲ J, the work output is then 18 × 1×10⁻²ⁱ⁲ J. The energy input is the energy of one ATP molecule, which is 5.1×10⁻²⁰ J.

Now, we can calculate the efficiency:

Efficiency = ((18 × 1×10⁻²ⁱ⁲ J) / (5.1×10⁻²⁰ J)) × 100% = 0.353×10² % = 35.3%

This calculation reveals that the efficiency of the power stroke in muscle contraction is 35.3%.