Question

How is air taken directly to the muscles in a grasshopper?

Answer 1

To survive in the environment all insects are treated as aerobic organisms; they must receive oxygen from their surroundings. To converts nutrients into the chemical bond energy of ATP, they take help of the same metabolic reactions as other species. Oxygen atoms get connected with hydrogen ions to create water at the time of the final stage of this process, releasing energy that is captured in an ATP phosphate bond.

Complete answer:
Separate from the circulatory system is the respiratory system that is present in insects and many other arthropods. It is shown as a complicated tube network that is termed as a tracheal system that transfers air containing oxygen to every cell of the body.
With the help of valve-like openings in the exoskeleton, air enters the body of the insect. These openings are present laterally along most insects' thorax and abdomen, usually one pair of spiracles per segment of the body. Air flow is usually controlled by small muscles that are present inside each spiracle that operate one or two flap-like valves, contracting to close the spiracle or relaxing to open it.

Air gets inside a longitudinal tracheal trunk after crossing through a spiracle, spontaneously spreading across a complex, branching network of tracheal tubes that further divides into smaller and smaller diameters and reaches every part of the body. A special cell gives a thin, moist interface at the end of each tracheal branch usually for the exchange of gases between atmospheric air and a living cell. In the tracheal channel, oxygen gets soluble and dissolves first in the tracheolic fluid and after that it diffuses into the cytoplasm of the neighbouring cell. At the same time, carbon dioxide is expelled out as a waste product of cellular respiration, diffuses out of the cell and, ultimately, out of the body via the tracheal system.

Note: In a way to transfer gases inside the tracheal system, small insects uses almost entirely on passive diffusion and physical activity. Larger insects, however, can require active ventilation of the tracheal system.