In the body, the sarcomere length of skeletal muscle cells is usually In the body, the sarcomere length of skeletal muscle cells is a. usually 3 microns. b. much less than optimum length. c. much greater than optimum length. d. near optimal. e. quite variable from one muscle to the next.

d

explanation:

the higher the instrument the better

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.