Why is blood flow to the brain relatively continuous and constant?

Vern is suffering from cardiac arrhythmias and is brought into the emergency room of a hospital. In the emergency room he begins to exhibit tachycardia and as a result loses consciousness. Explain why Vern lost consciousness.

When we are cold or the external temperature is low, most venous blood returning from the distal part of the arm travels in the deep veins where it picks up heat (by countercurrent exchange) from the nearby brachial artery en route. However, when we are hot, and especially during exercise, venous return from the distal arm travels in the superficial veins and those veins tend to bulge superficially in a person who is working out. Explain why venous return takes a different route in the second situation.

Which of the following would not result in the dilation of the terminal arterioles and upstream arterioles in systemic capillary beds?a. a decrease in local tissue O₂ content,b. an increase in local tissue CO₂,c. a local increase in histamine,d. a local increase in pH.

Compare the effects of the cardioacceleratory and cardioinhibitory centers on cardiac output and blood pressure.

Bob is sitting outside on a warm day and is sweating profusely. Mary wants to practice taking blood pressures, and he agrees to play the patient. Mary finds that Bob's blood pressure is elevated, even though he is resting and has lost fluid from sweating. (She reasons that fluid loss should lower blood volume and, thus, blood pressure.) Why is Bob's blood pressure high instead of low?

Blood is transported through the venous system by means of (a) skeletal muscle contractions, (b) decreasing blood pressure, (c) the respiratory pump, (d) a and c.

The most important factor in vascular resistance is (a) the viscosity of the blood, (b) the diameter of the lumen of blood vessels, (c) turbulence due to irregular surfaces of blood vessels, (d) the length of the blood vessels.