A&P2- the heart pt 2 & blood vessels

Determine the net filtration pressure (NFP) if capillary hydrostatic pressure is 40 mm Hg and the colloid osmotic pressure is 25 mm Hg.

15 mm Hg

Calculate the end-systolic volume (ESV) if the end-diastolic volume (EDV) in a resting heart is 110 ml and stroke volume (SV) is 70 ml.

40 ml

Which of the following chemical messengers decreases heart rate?

Acetylcholine

Which of the following molecules decreases heart rate, and thus cardiac output and blood pressure?

Acetylcholine

Which of the following terms refers to the force the ventricles must overcome to eject blood into their respective arteries?

Afterload

____ carry blood away from the heart, whereas ___ carry blood toward the heart.

Arteries; veins

Which of the following events is not part of the cardiac cycle?

Atrial contraction phase

Which hormone decreases cardiac output by decreasing blood volume and preload?

Atrial natriuretic peptide

Which of the following hormones does not act to increase blood pressure?

Atrial natriuretic peptide (ANP)

Which of the following hormones is released to decrease blood pressure?

Atrial natriuretic peptide (ANP)

________ is(are) not one of the three main factors that influence blood pressure.

Blood reservoirs

Which of the following can be heard with a stethoscope most easily?

Closing of atrioventricular valves

Which pressure remains the same along the length of a capillary?

Colloid osmotic pressure

Which of the following factors does not contribute to venous blood return?

Contractions of the right ventricle of the heart

Which of the following stimuli is detected by a chemoreceptor?

Decreased blood oxygen concentration

Which of the following factors influences blood volume?

Dehydration

What largely determines preload?

End-diastolic volume (EDV)

Which of the following factors may contribute to an increase in stroke volume?__________.

Increase preload and contractility, and decrease afterload

_______ will not cause an increase in arterial blood pressure.

Increased arteriolar vasodilation

Which of the following factors would increase cardiac output to the greatest extent?

Increased heart rate and increased stroke volume

During what phase is the S1 heart sound first heard?

Isovolumetric contraction phase

Which chamber generates the highest pressure during systole?

Left ventricle

Which of the following arteries has the smallest diameter?

Metarteriole

Sometimes health care providers will elect not to treat conditions such as atrial fibrillation in which there is no functional atrial contraction. Select the logic behind this.

Most of the blood drains from the atria passively into the ventricles.

How would a poison that breaks down capillary tight junctions, allowing blood proteins to leak into the interstitial fluid, effect the colloid osmotic pressure?

Osmotic pressure in the interstitial fluid would rise, eventually causing the pressure between the interstitial fluid and the blood in the capillaries to equalize, decreasing the movement of water back into the capillaries. Submit

Under what conditions will the myogenic mechanism slow blood flow into a capillary bed?

Rising arteriolar pressure

What type of capillaries have large pores within their endothelial cells and are the leakiest?

Sinusoidal capillaries

What is the volume of blood pumped out by one ventricle per heart beat?

Stroke volume (SV)

What two values are needed to calculate cardiac output (CO) for a ventricle?

Stroke volume (SV) and heart rate (HR)

What is edema?

Swelling

Which blood vessels handle the highest blood pressure?

Systemic arteries

Predict the position of the valves during the ventricular ejection phase.

The AV valves are shut while both semilunar valves are forced open.

What best describes the Frank-Starling law?

The Frank-Starling law states that the more the ventricular muscle cells are stretched, the more forcefully they contract.

Arteries contain multiple sheets of elastic fibers between thin layers of smooth muscles. What would happen if these fibers became faulty?

The arteries would either be noncompliant, or unable to stretch, or unable to recoil after stretching. Submit

A new form of biological warfare is a poison that destroys the tight junctions of the continuous capillaries in the brain. What effects would be expected?

The continuous capillaries of the brain form the blood brain barrier and if disrupted, pathogens and toxins could enter into the brain's interstitial fluid. Submit

Mary was in a terrible car accident. When the emergency personnel arrived, they noticed she had significant blood loss. What was their concern about her blood pressure?

They were concerned her blood pressure would be extremely low, which could be fatal due to not enough oxygen reaching her cells, leading to organ failure.

How will the hydrostatic pressure gradient and net filtration pressure be affected in a patient who is suffering from hypotension?

They will have a reduced hydrostatic pressure gradient, causing the net filtration pressure to favor absorption instead of filtration. Submit

Why aren't capillaries made of thicker epithelium?

Thicker epithelium would decrease the diffusion of gases and nutrients between the blood and tissues.

The myogenic mechanism counters changes in blood flow through capillary beds by altering arterial resistance.

True

The sinoatrial (SA) node fires more rapidly at higher body temperatures, increasing cardiac output.

True

The sympathetic nervous system increases cardiac output by increasing both heart rate and stroke volume.

True

Which cranial nerves have a negative chronotropic effect on heart rate?

Vagus nerves (CN X)

_____ increases the diameter of a blood vessel.

Vasodilation

In which direction will water move when hydrostatic pressure exceeds colloid osmotic pressure at the arteriolar end of a capillary?

Water is pushed out of the capillary by filtration.

According to the Frank-Starling law, a bigger preload will result in __________.

a stronger contraction

Which of the following decreases heart rate, and thus cardiac output and blood pressure?

acetylcholine

All of the following pairs correctly match the mechanisms affecting blood pressure with its effect except:

aldosterone; decreased blood volume.

A decrease in blood pressure at the arterial baroreceptors would result in which of the following?

an increase in heart contractility

Stimulation of the adrenal medulla would result in which of the following?

an increase in heart rate and contractility

A negative feedback mechanism will cause _____ if blood pressure drops.

an increase in heart rate, stroke volume, and vasoconstriction

Which of these would NOT increase pressure on the vessel walls?

an increase in the diameter of the vessels

Tissue perfusion is largely controlled by ______ to ensure that blood flow meets the cells' needs.

autoregulation

The most important force driving reabsorption at the venous end of a capillary is _____.

blood colloid osmotic pressure

Water in the blood exerts pressure on the walls of capillaries, generating ________.

blood hydrostatic pressure

Peripheral resistance includes all of the following EXCEPT:

blood type.

At the arteriolar end of the capillary, which pressure is the greatest?

capillary hydrostatic pressure Submit

Where are the sensors for the arterial baroreceptor reflex located?

carotid sinus and aortic arch

The beginning of the QRS complex of the electrocardiogram (ECG) immediately precedes which of the following events?

closing of the atrioventricular valves

Which pressure pulls water into the capillary?

colloid osmotic pressure

Pulmonary arteries have ____ blood pressure compared to systemic arteries.

considerably lower

Inotropic agents affect __________.

contractility

Which of the following would cause vasodilation of arterioles?

decreased activity of the sympathetic nervous system

Which mechanism allows lipid-soluble substances to move through the membranes of endothelial cells of capillaries?

diffusion

An excess amount of water in the interstitial fluid is known as ____.

edema

What type of vessel is built to handle the highest pressure of any vessel in the cardiovascular system?

elastic artery

There are two phases of the cardiac cycle in which all four heart valves are open: the isovolumetric contraction phase and the isovolumetric relaxation phase.

false

Small solutes can pass through small pores in some capillaries known as ____.

fenestrations

High-pressured blood in the ventricles ________.

forces the semilunar valves open

Blood pressure is equivalent to __________.

hydrostatic pressure

Decreased cardiac output may lead to ____.

hypotension

If blood pressure is increased at the arterial baroreceptors, what would happen with the activity level of the parasympathetic nervous system (PNS) and sympathetic nervous system (SNS)?

increased PNS activity and decreased SNS activity

Which of the following vessels has the lowest blood pressure?

inferior vena cava

As ventricular systole begins, all four heart valves are closed during the:

isovolumetric contraction phase.

Large vessels with all three tunics and a well-developed tunica media are called __________.

muscular arteries

Net filtration pressure (NFP) is equal to the:

net hydrostatic pressure minus the net colloid osmotic pressure.

Blood flow through the capillary bed is regulated by ______.

precapillary sphincters

The degree of stretch experienced by the sarcomeres in the ventricle cells before they contract is called __________.

preload

Blood flow is directly proportional to _____ and inversely proportional to ____.

pressure gradient; resistance

The ____ is the only route in which arteries carry less oxygen than veins.

pulmonary circuit

Archie took several deep breaths of air. By breathing deeply, what mechanism did he assist to return venous blood to his heart?

respiratory pump

Afterload is described as:

the force the ventricles must overcome to eject blood into their respective arteries.

Large, lipid-insoluble molecules cross capillary walls by ___.

transcytosis

Atrial natriuretic peptide (ANP) causes vasodilation resulting in a mild decrease in peripheral resistance and blood pressure.

true

Pressure in the aorta is greater than pressure in the pulmonary trunk; therefore, the left ventricle has to generate a greater pressure than the right ventricle in order to eject blood from the heart.

true

The innermost layer of blood vessels, that is composed of endothelium, is known as ____.

tunica intima

Which blood vessel tunic is innervated by nerves from the sympathetic nervous system?

tunica media