BV Anatomy and Hemodynamics Blackboard Quiz

The mean arterial pressure is

diastolic pressure plus 1/3 (systolic pressure - diastolic pressure)

As the arterial system leaves the heart, the vessels

divide and branch, become less elastic and more muscular, become smaller in diameter, usually but not always carry oxygenated blood

An increase in the volume of blood ejected from the heart, with no change in total peripheral resistance, would ____________.

elevate mean arterial pressure

An increase in total peripheral resistance, in the absence of any change in cardiac output, would -elevate mean arterial pressure -reduce the stretch on the aorta -elevate central venous pressure -elevate pulmonary venous pressure -reduce mean arterial pressure

elevate mean arterial pressure

Which of the following is not one of the three main factors influencing blood pressure? -cardiac output -peripheral resistance -emotional state -blood volume

emotional state

Select the correct statement about factors that influence blood pressure

excess red cell production would cause a blood pressure increase

The circulatory route than runs from the digestive tract to the liver is called:

hepatic portal circulation

A portal system differs from a typical circulatory pathway in that a portal system -carries oxygenated blood to the heart. -lacks a capillary bed so that arteries and veins are directly linked. -provides an alternative route for blood flow to bypass a capillary bed. -includes two arteries that merge to provide alternative blood supply to an organ or tissue. -includes two capillary beds linked by a portal vessel.

includes two capillary beds linked by a portal vessel.

In response to a decrease in tissue metabolic activity, tissue oxygen concentrations _____, which causes __________. -decrease; dilation of the arterioles -decrease; relaxation of precapillary sphincters -increase; constriction of the arterioles and precapillary sphincter -decrease; constriction of the thoroughfare channel -increase; constriction of venules

increase; constriction of the arterioles and precapillary sphincter

Which of the following would increase the rate of blood flow through a blood vessel? -increased length of the vessel -decreased radius of the vessel -constriction of the blood vessel -increased upstream pressure -increased viscosity of the blood

increased upstream pressure

Peripheral resistance: -does not have a significant effect on blood pressure in healthy individuals. -decreases with increasing blood vessel distance from the heart. -increases as blood vessel diameter increases. -decreases with increasing length of the blood vessel. -increases as blood viscosity increases.

increases as blood viscosity increases.

Blood flow is __________ proportional to resistance and _____________ proportional to the blood pressure gradient. -inversely, inversely -directly, directly -inversely; directly -directly, inversely

inversely; directly

Blood pressure is lowest in the

large veins

The arteries that are also called distributing arteries are the: -elastic arteries. -muscular arteries. -arterioles. -capillaries.

muscular arteries.

Elastic arteries function as -vasoconstrictors only. -pressure reservoirs. -capacitance reservoirs. -pulmonary vessels only. -a conduit to the tissues of the trunk only.

pressure reservoirs.

A person goes to the doctors and is told his blood pressure is 90/60 and his pulse is 80. What is false?

pulse pressure is 80 mm Hg

Chemicals released by metabolically active cells will cause which of the following localized changes? -contraction of arteriolar smooth muscle to increase blood flow -contraction of arteriolar smooth muscle to decrease blood flow -relaxation of arteriolar smooth muscle to increase blood flow -relaxation of capillary smooth muscle to decrease blood flow -contraction of capillary smooth muscle to increase blood flow

relaxation of arteriolar smooth muscle to increase blood flow

All of the veins of the systemic circulation drain into the ______________ before returning to the heart. -Inferior vena cava -Superior vena cava -Pulmonary veins -Superior and inferior vena cavae -Pulmonary trunk

Superior and inferior vena cavae

The values obtained when taking blood pressure, such as 120/80, -exactly match the pressures inside the ventricle during systole and diastole. -represent the pressure in the major arteries during ventricular systole and diastole. -are the same in both the pulmonary and systemic circuits. -reflect the difference in blood pressure between the aorta and arterioles. -reflect the pressures associated with atrial and ventricular systole.

represent the pressure in the major arteries during ventricular systole and diastole.

As blood travels from the aorta towards the capillaries, the

resistance increases

Blood flow through the vascular system is affected by all of the following, except:

rhythmic contractions of the blood vessels

The large lumens and thin walls of veins allow them to

accommodate large volumes of blood and function as capacitance reservoirs

Which of the following changes would lead to a decrease mean arterial pressure?

an increase in arteriolar diameter

Continuous capillaries: -have oval pores to facilitate the delivery of oxygen and nutrients to tissues. -are abundant in the skin and skeletal muscles. -have a thin layer of muscle tissue to autoregulate blood flow. -contain a layer of connective tissue to prevent protein leakage.

are abundant in the skin and skeletal muscles.

Fenestrated capillaries:

are not found in the brain

The pulsatile nature of blood pressure is greatest in which blood vessels?

arteries

The contractile activity of smooth muscle cells within _________ is primarily involved in the control of the organ blood flow and mean arterial pressure. -veins -venules -capillaries -arterioles -arteries

arterioles

The arteries that directly feed into the capillary beds are called: -muscular arteries. -elastic arteries. -arterioles. -venules.

arterioles.

_______ depends mostly on the ratio of RBC to plasma volume

blood viscosity

The velocity of blood flow is slowest in the

capillaries

Permitting the exchange of nutrients and gases between the blood and tissue cells is the primary function of: -capillaries. -arterioles. -veins. -arteries. -venules.

capillaries.

Which of the following factors does NOT increase peripheral vascular resistance? a. increased vasoconstriction b. increased blood viscosity c. decreased vessel length d. increased blood cell count e. decreased vessel lumen diameter

decreased vessel length

The influence of blood vessel diameter on peripheral resistance is: -the only factor that influences resistance. -significant because resistance is inversely proportional to the fourth power of the vessel radius. -significant because resistance is directly proportional to the blood vessel diameter. -insignificant because vessel diameter does not vary.

significant because resistance is inversely proportional to the fourth power of the vessel radius.

Most of the total blood volume is in the ______ at any given time.

systemic veins

The driving force for blood flow

the pressure produced as blood is ejected from the heart

This layer of an artery is composed mainly of elastic and collagen fibers. -tunica interna -tunica albuginea -tunica media -tunica externa -tunica fascia

tunica externa

Which tunic of an artery contains endothelium? -tunica interna (intima) -tunica media -tunica externa -tunica adventitia

tunica interna (intima)

Capillary walls would consist of which of the following layers?

tunica intima

Histologically, the ________ is squamous epithelium supported by sparse connective tissue layer.

tunica intima (interna)

Which tunic of an artery is most responsible for maintaining blood pressure and continuous blood circulation?

tunica media

Each of the following factors would increase peripheral resistance, except -vasodilation. -factors that lead to an increased hematocrit. -increased sympathetic stimulation. -irregularities in the vessel walls caused by plaques. -elevated levels of epinephrine.

vasodilation.