Blaberus Giganteus - Muscle Metabolism and Respiratory System

Muscle Metabolism and Respiratory System

The rate of oxygen consumption in some animals and in insects is proportionate to body weight. Oxygen consumption will increase with activity and will be subject to rhythmical cycles of activity exhibited in cockroaches. Because cockroaches do not have lungs to breathe, they take in air through small holes on the sides of the body known as spiracles. Attached to these spiracles are tubes called tracheae that will branch throughout the body of the cockroach until they associate with each cell. Oxygen will diffuse across the thin cuticle and carbon dioxide will diffuse out, and this allows cockroaches to deliver oxygen to cells directly without relying on blood like humans. There can be differences in oxygen consumption between sexes of the same organism. Oxygen consumption in the mixed red and white muscles of mature male B. giganteus was higher when compared to mature females. This is likely due to sex-related differences of sex hormones causing increased accumulation of oxidized substrates or increased concentration of enzymes in muscles in males. Males have been shown to have higher levels of glycogen and mitochondria in muscle cells. Because B. giganteus is so large, they are assumed to have a higher metabolic rate versus other cockroaches, such as Periplaneta americana, but in comparison they are quite sluggish. Rates of oxygen consumption are significantly higher in P. americana when compared to B. giganteus likely due to higher daily rhythmic activity.