Local metabolic activity is the chief factor determining the rate of blood flow to the

A. True   There is a close relationship between the work of the heart and coronary flow.

B. False   Skin blood flow is geared mainly to thermoregulation and normally exceeds that needed for skin’s modest metabolic requirements.

C. True   Local blood flow is largely determined by the vasoactive metabolites such as rising PCO2, H concentration and falling PO2. The changes produced by vasomotornerves are small compared with those produced by metabolites.

D. False   The entire cardiac output must pass through the lungs regardless of the local metabolic needs of the pulmonary tissues. It is greatly in excess of the lungs’ metabolic needs.

E. False   As in skin, renal blood flow (about one quarter of total cardiac output) greatly exceeds local metabolic needs. The blood is sent to the kidneys for processing.