The transformation of this energy and matter within the body is called metabolism. The immediate source of energy for most cells is glucose. But glucose is not the only fuel on which cells depend. Other carbohydrates, fats and proteins may in certain cells or at certain times be used as a source of ATP.
The process of muscle contraction requires several steps.
The most famous theory on how the contraction and relaxation of muscles take place is the sliding filament theory.
However, this theory has been refined and one important addition to it is the mechanism by which myosin can pull actin and cause shortening of the sarcomere.
For the movement of myosin, it binds and releases actin and forms cross bridges.
Myosin is subdivided into two regions - S1 and S2. The contraction of the S1 region is what constitutes the power stroke.
An important requirement of the power stroke is the hydrolysis of ATP to release an inorganic phosphate which provides energy for the process.
In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes.
The exponential growth occurs when the resources are unlimited to the population of the species. The population grows rapidly at a constant rate. Thus the population size increases over concerned period of time. When the resources become limited the growth collapses this is called as logistic growth.
The exponential growth can be shown by the J-shaped curve.
