You Have Used "Optical Tweezers" to Study the Mechanics of Myosin

question 36

Short Answer

You have used "optical tweezers" to study the mechanics of myosin movement in a newly discovered member of the myosin II subfamily. Your results indicate that each myosin exerts a force of about 3 pN along the length of the actin filament, and displaces the filament by about 10 nm in each cycle of ATP hydrolysis. Assuming that the free-energy change for ATP hydrolysis is -50 kJ/mol under your experimental conditions, what is the efficiency of the myosin motor in converting the free energy to mechanical work? Remember that under a constant force F (in newtons), work (W; in joules) is calculated as W = F × d, where d is displacement (in meters) in the direction of the force. Avogadro's number is approximately 6 × 10²³ molecules/mole. Write down your answer as a percentage with no decimals, e.g. 99%.

Understand the role of community resources in supporting educational outcomes.

Recognize the importance and methods of effective communication between schools, families, and communities.

Describe the principles of asset-based and family-centered approaches in education.

Understand the importance and impact of service-learning and place-based education on student learning.

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Definitions:

Variable Overhead

Costs of overhead that vary with the level of production activity, such as utilities for machinery or materials handling expenses.

Predetermined Overhead Rate

An estimated rate used to allocate manufacturing overhead costs to individual units of production based on a certain activity base.

Variable Component

The part of a cost or expense that varies directly with the level of activity or production volume, in contrast to fixed costs.

Electrical Motor

An electromechanical device that converts electrical energy into mechanical energy, commonly used in various appliances, machinery, and vehicles.