Speed is a complex skill that requires the communication of which systems to function?
select all that apply.
skeletal system
circulatory system
respiratory system
muscular system

The correct answer will be options- skeletal system and muscular system

Explanation:

The movement of the body is provided by the action of many of all the complex biological systems but he directly influenced by the coordination of the skeletal system with the muscular system.

The coordination of these two systems forms the "Musculoskeletal system' which provides shape, stability and movement to the body. In this system skeletal system protect the organs of the body whereas the muscle attached to the bones allow these bones to move.

Thus, the selected options are the correct answer.

both anaerobic and aerobic respiration use glucose (or other carbohydrates), proteins and lipids to produce atp and nadh. cell uses those energy molecules, obtained from food and   breaks them down during the chemical reactions of respiration. in anaerobic respiration, nadh is regenerated to nad+ by enzymes lactate dehydrogenase (lactate is produced, e.g. in muscle cells) or by alcohol dehydrogenase where ethanol is produced (alcohol fermentation), while in aerobic respiration, electrons from nadh are deposited in the mitochondria to regenerate nad+ (electron transport chain. anaerobic respiration produces 2 atp per molecule of glucose compared to aerobic respiration where about 38 atp molecules are produced.

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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