CHAPTER 14

If an arteriole could dilate to four times its normal radius, the rate of blood flow through it would increase to

256 times the minimal flow

If someone's heart has a stroke volume of 70 ml, beats 80 times/minute

5.6 L/min

Contraction of the left ventricle of the heart at rest normally expels about ____ of the blood contained in the chamber.

60-70%

____ is a polypeptide vasodilator produced by the sweat glands

Bradykinin

____ stimulates the heart by inhibiting cardiac membrane Na+/K+ pumps and ultimately raising the intracellular Ca2+ concentration in the myocardium.

Digitalis

A young man is involved in an automobile accident and suffers injuries resulting in blood loss. Which of the following would occur in an attempt to maintain homeostatsis?

Increased renin secretion.

Which of the following is not true regarding hypertension?

It may be caused by aortic arteriosclerosis.

A young woman is brought to the emergency room in the early stages of shock. After stabilizing the patient, the attending physician evaluates the results of clincal tests run and notices that concentration of endotoxin in the woman's blood is very high. Which type of shock is the woman experiencing?

Septic shock.

Hypertension would be present in an adult with

a diastolic blood pressure of 95 mm Hg.

Coronary arteries must dilate during exercise to meet the heart's increased oxygen demand. This occurs under the influence of all of the following compounds, except

acetylcholine

The colloid osmotic pressure of blood plasma is due to its high concentration of ____.

albumin

The "salt-retaining hormone," secreted in response to low blood pressure, is called

aldosterone

Which of the following would not cause edema?

an elevated level of albumin in the blood plasma

A bee sting is most likely to cause

anaphylactic shock

The enzyme that produces angiotensin II directly in the plasma, is

angiotensin-converting enzyme (ACE)

According to the classic view of the Starling forces, capillaries usually tend to absorb fluid

at the venular end.

During moderate exercise

blood flow increases to skeletal muscle due to intrinsic metabolic control mechanisms.

Stroke volume is regulated by all of the following except

cardiac output

The amount of blood pumped by one ventricle in one minute, is called the

cardiac output

Baroreceptors are specialized pressure receptors found in the

carotid sinuses

Stretch receptors in the left atrium help control blood pressure by

causing increased urine output

Any mechanism that slows down the heart is said to have a negative ____ effect.

chronotropic

Veins are said to have a higher ____ than arteries because they stretch more easily and a higher ____ because they contain more blood.

compliance; capacitance

The contractility of a muscle fiber is its

contraction strength at a particular fiber length.

Extrinsic control of blood flow refers to the

control of blood flow by the nervous and endocrine systems.

Vasodilation is often caused by any of the following local conditions except the

decrease in carbon dioxide concentration in the tissue fluid.

Filtration from the blood into the interstitial fluid would be increased by

decreased blood plasma colloid osmotic pressure.

Cardiac output is increased by

decreased parasympathetic outflow to the heart.

Local vasodilation can be induced by

decreased tissue pH.

Arteriovenous anastomoses are found mainly in the

dermis of the skin

The preload acting on a ventricle is equivalent to that chamber's

end-diastolic volume

Natriuretic hormone helps to lower blood pressure and is secreted by the

heart

During exercise the cardiac output may rise to five times the resting value. In most people this is due mainly to an increase in

heart rate

Blood will not flow unless there is a sufficient DP between point A and point B in the circulatory system. In this sentence DP represents

hydrostatic pressure difference

Osmoreceptors regulating the release of ADH are found in

hypothalamus

Excessive blood loss due to a gunshot wound is most likely to cause

hypovolemic shock

Athletes trained for endurance, such as swimmers and marathon runners, have a higher stroke volume at rest mainly because they have

increased end-diastolic volume

Myxedema is a disease caused by hypothyroidism, which causes production of excessive amounts of glycoprotein in the interstitial spaces. The effect of this on capillary fluid dynamics would be to cause

increased filtration and accumulation of fluid in the tissues

Blood flow would be increased in response to

increased plasma nitric oxide concentrations.

A positive inotropic effect is something that

increases the contractility of myocardial fibers.

Autoregulation of the blood vessels means essentially the same thing as ____ regulation.

intrinsic

Pulmonary edema, shortness of breath, and fatigue are most likely to result from

left-sided congestive heart failure

Congestive heart failure

may result from excessively low blood Ca2+.

The auscultatory method is used for

measuring blood pressure

During systole, the ventricular myocardium gets its oxygen supply mainly from

myoglobin

Elephantiasis is caused by

nematode worm parasite

The sympathoadrenal system can raise blood pressure by doing any of the following, except

promoting a negative inotropic effect on the heart

Angiotensin II has all of the following effects except to ____.

stimulate excretion of excess sodium by the kidneys.

The normal action of antidiuretic hormone (ADH) is to

stimulate fluid retention by the kidneys.

The Frank-Starling law of the heart pertains to stroke volume and essentially says that

stroke volume is proportional to the EDV

In response to decreased arterial blood pressure

sympathetic discharge to the heart increases

If the hydrostatic pressure (P) of the blood in a capillary is 19 mmHg and that of the tissue fluid is 1mmHg, while the colloid osmotic pressure (π) of the blood is 23 mmHg and that of the tissue fluid is 0 mmHg, then is the capillary at this point giving off fluid or taking up fluid, and what is the net Starling force? The formula for the Starling forces is: (Pc + πi) - (Pi + πh).

taking up fluid with a net force of -5 mmHg

The Frank-Starling Law of the Heart describes

the intrinsic relationship between end-diastolic volume and stoke volume.

During exercise or stress ("fight-or-flight" situations), the sympathetic nervous system causes vasodilation in the skeletal muscle but vasoconstriction in the skin. It is able to achieve these opposite effects because

the muscles have cholinergic sympathetic fibers and the skin has adrenergic fibers.

When utilizing the sounds of Korotkoff to measure blood pressure

the sounds produced are due to turbulent blood flow.

The afterload imposed on a ventricle refers to

the total peripheral resistance opposing the ejection of blood.

The sinoatrial (SA) node depolarizes less frequently under the influence of

the vagus nerve

Cardiac output may drop when one goes from a lying to a standing position because of

venous pooling

Of all the factors that can affect blood flow to a particular tissue, the most effective and easiest to control from moment to moment, is

vessel radius

In the proportionality expression R ∞ Lη / r4, R represents the total force that resists the flow of blood from point A to point B, and h represents the

viscosity of the blood.