Chapter 42 Circulation Final
Fluid is filtered from blood as it enters a capillary due to the _____, but fluid is reabsorbed as the blood exits a capillary due to the _____.
blood pressure from the heart; osmotic pressure from proteins in the plasma
Which of the following have valves within them to prevent blood backflow?
veins
Which of the following mechanisms are used to regulate blood pressure in the closed circulatory system of vertebrates? I) changing the force of heart contraction II) constricting and relaxing sphincters in the walls of arterioles III) adjusting the volume of blood contained in the veins
I, II, and III
Organisms with a circulating body fluid that is distinct from the fluid that directly surrounds the body's cells are likely to have _____.
a closed circulatory system
The normal contraction of specialized atrial cells results from the activity of the _____, and the simultaneous contraction of the left and right atria is due to the _____.
autorhythmic pacemaker cells; gap junctions
The only vertebrates in which blood flows directly from respiratory organs to body tissues without first returning to the heart are the _____.
fishes
If, during protein starvation, the osmotic pressure on the venous side of capillary beds drops below the hydrostatic pressure, then _____.
fluids will tend to accumulate in tissues
Small swollen areas in the neck, groin, and axillary region are associated with _____.
increased activity of the immune system
In an open circulatory system, blood is _____.
not always confined to blood vessels and is under lower pressure than in closed circulatory systems
Circulatory systems compensate for _____.
the slow rate at which diffusion occurs over large distances
A human red blood cell in an artery of the left arm is on its way to deliver oxygen to a cell in the thumb. To travel from the artery to the thumb and then back to the left ventricle, this red blood cell must pass through _____.
two capillary beds
Which of the following is the correct sequence of blood flow in birds and mammals?
vena cava, right atrium, right ventricle, pulmonary artery