31 notecards = 8 pages (4 cards per page)
Which statement does not accurately describe veins?
D)Always carry deoxygenated blood
Smooth muscle in the blood vessel wall:
B)is mostly circularly arranged
D)is inversely related to the diameter of the arterioles
Which of the following can lead to decreased venous return of blood to the heart?
C)damage to the venous valves
Arterial blood pressure increases in response to:
E)all of these
Which of the following would not result in the dilation of the feeder arterioles and opening of the precapillary sphincters in systemic capillary beds?
D)a local increase in pH
The structure of a capillary wall differs from that of a vein or an artery because:
C)it has a single tunic- only the tunica intima
The baroreceptors in the carotid sinus and aortic arch are sensitive to:
B)changes in arterial pressure
The myocardium receives its blood supply directly from the:
Blood flow in the capillaries is steady despite the rhythmic pumping of the heart because of the:
A)elasticity of the large arteries
Using the letters from column B, match the artery descriptions in column A. (some require more than a single choice)
b,e,g (1) unpaired branch of abdominal aorta
Tracing the blood from the heart to the right hand, we find that blood leaves the heart and passes through the aorta, the right subclavian artery, the axillary and bracbial arteries, and through either the radial or ulnar artery to arrive at the hand. Which artery is missing from this sequence?
Which of the following do not drain directly into the inferior vena cava?
C)inferior mesenteric vein
Suppose that at a given point along a capillary, the following forces exist: capillary hydrostatic pressure (HPc) = 30 mmHg, interstitial fluid hydrostatic pressure (HPif) = 0 mmHg, capillary colloid osmotic pressure (OPc) = 25 mmHG, and interstitial fluid colloid osmotic pressure (OPic) = 2 mmHg. The net filtration pressure at this point in the capillary is:
How is the anatomy of capillary bed and capillaries suited to their functions?
Capillaries walls are very thin this allows maximal delivery of the nutrients. They have pores for exchange, and are devoid of muscle and connective tissue. (p. 696)
Distinguish between elastic arteries, muscular arteries, and arterioles relative to location, histology, and functional adaptations
•Elastic arteries are the large, thick-walled arteries close to the heart. They have generous amounts of elastic tissue in all tunics, but especially in the tunica media. This elastic tissue enables them to withstand large pressure fluctuations by expanding when the heart contracts, forcing blood into them. They recoil as blood flows forward into the circulation during heart relaxation. They also contain substantial amounts of smooth muscle but are relatively inactive in vasoconstriction. (p. 695)
Write an equation showing the relationship between peripheral resistance, blood flow, and blood pressure.
Blood Flow = (B.P. 1 – B.P. 2) / Resistance. (p. 702)
Define blood pressure.
Blood pressure is the force per unit area exerted on the wall of a blood vessel by the blood contained within it. Systolic pressure is the pressure that occurs during systole when the aortic pressure reaches its peak. Diastolic pressure is the pressure that occurs during diastole when aortic pressure drops to its lowest level. (p. 703)
Describe the neural mechanisms responsible for controlling blood pressure.
The neural controls responsible for controlling blood pressure operate via reflex arcs chiefly involving the following components: baroreceptors and the associated afferent fibers, the vasomotor center of the medulla, vasomotor (efferent) fibers, and vascular smooth muscle. The neural controls are directed primarily at maintaining adequate systemic blood pressure and altering blood distribution to achieve specific functions. (pp. 705–707)
Explain the reasons for the observed changes in blood flow velocity in the different regions of the circulation?
Changes in the velocity in different regions of the circulation reflect the cross-sectional area of the vascular tubes to be filled. Because the cross-sectional area is least in the aorta and greatest in the capillaries, the blood flow is fastest in the aorta and slowest in the capillaries. (p. 712)
how does the control of blood flow to the skin for the purpose of regulating body temperature differ from the control of nutrient blood flow to skin cells
Nutrient blood flow to the skin is controlled by autoregulation in response to the need for oxygen, whereas blood flow for regulating body temperature is controlled by neural intervention, that is, the sympathetic nervous system. (p. 712)
Describe neural and chemical (both systemic and local) effects exerted on the blood vessels when one is fleeing from a mugger?
When one is fleeing from a mugger, blood flow is diverted to skeletal muscles from other body systems not in direct need of large volumes of blood. Blood flow increases in response to acetylcholine release by sympathetic vasodilator fibers and/or epinephrine binding to beta receptors of vascular smooth muscles in the skeletal muscles, and virtually all capillaries open to accommodate the increased flow. Systemic adjustments, mediated by the sympathetic vasomotor center, occur to ensure that increased blood volume reaches the muscles. Strong vasoconstriction of the digestive viscera diverts blood away from those regions temporarily, ensuring that an increased blood supply reaches the muscles. Bloodborne epinephrine enhances blood glucose levels, alertness, and metabolic rate. The major factor determining how long muscles can continue vigorous activity is the ability of the cardiovascular system to deliver adequate oxygen and nutrients. (pp. 712–714)
How is nutrients, waste and respiratory gases transported to and from blood and tissue space?
Nutrients, wastes, and respiratory gases are transported to and from the blood and tissue spaces by diffusion. (p. 717)
(a) What blood vessels contribute to the formation of the hepatic portal circulation?
a. The veins draining the digestive viscera contribute to the formation of the hepatic portal circulation. The most important of these are the superior and inferior mesenteric veins and the splenic veins.
Physiologists often consider capillaries and postcapillary venules together.
a. The text states that postcapillary venules function “more like capillaries” (p. 698), meaning that exchanges of small molecules between the blood and the surrounding tissue fluid occur across these venules. Furthermore, inflammatory fluid and leukocytes leave the postcapillary venules just as they exit the capillaries.
The compensatory mechanisms of Mrs. Johnson induce an increase in heart rate and an intense vasoconstriction, which allows blood in various blood reservoirs to be rapidly added to the major circulatory channels. (p. 717)
If the sympathetic nerves are severed, vasoconstriction in the area will be reduced and vasodilation will occur. Therefore, blood flow to the area will be enhanced. (p. 705)
An aneurysm is a balloonlike outpocketing of a blood vessel that places the vessel at risk for rupture. In this case, the aneurysm was so large that it was pressing on the brain stem and cranial nerves, threatening to interfere with the functions of these structures. The surgeons removed the ballooned section of the artery and sewed a section of strong tubing in its place. (p. 750)
Harry’s condition suggests that this is a case of transient vascular shock. Marching in the severe heat of the day caused the cutaneous blood vessels to dilate, which resulted in an increased blood volume pooling in the lower limbs (because of gravity). A subsequent decrease in blood flow to the heart caused Harry’s blood pressure to drop, and his dizziness and fainting was an indication that the brain was not receiving enough blood flow (hence, oxygen). (p. 711)
Blood distribution is adjusted by a short-term neural control mechanism to meet specific demands. During exercise, the hypothalamus signals for reduced vasomotor stimulation of the skin vessels. Blood moves into the capillary beds, and heat radiates from the skin to reduce body temperature. (p. 716)
The lymphatic vessels can no longer drain the right arm, so fluid pools in the arm causing swelling. The compression sleeve would increase the interstitial fluid hydrostatic pressure and would decrease the amount of fluid leaking from the capillaries in the right arm. (p. 719)