Ch. 18 The Cardiovascular System II: The Blood Vessels

Amerman - Human Anatomy & Physiology 2nd Edition

Amerman2nd EditionHuman Anatomy & PhysiologyISBN: 9780136873822Not the one you use?Change textbook

Amerman 2nd Edition

Ch. 18 The Cardiovascular System II: The Blood Vessels

Problem L2.1

Chapter 18, Problem L2.1

Explain why a severed artery spurts blood, whereas a severed vein merely leaks blood.

Verified step by step guidance

Understand the difference in blood pressure between arteries and veins: Arteries carry blood away from the heart under high pressure due to the forceful pumping action of the heart, while veins return blood to the heart under much lower pressure.

Recognize the structural differences between arteries and veins: Arteries have thicker, more elastic walls to withstand high pressure, whereas veins have thinner walls and rely on valves to prevent backflow of blood.

Consider the dynamics of blood flow: In arteries, the high pressure causes blood to be ejected forcefully in spurts, corresponding to the rhythmic contractions of the heart (systole). In veins, the lower pressure results in a slower, steady leakage of blood when severed.

Relate the spurt of blood from arteries to the pulsatile nature of arterial blood flow: The heart's pumping action creates a pulse that drives blood through arteries in bursts, which is why a severed artery spurts blood in rhythm with the heartbeat.

Understand the clinical implications: The high-pressure spurt from a severed artery can lead to rapid blood loss and is a medical emergency, whereas the slower leakage from a vein is less immediately life-threatening but still requires attention to prevent infection or further complications.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Blood Pressure

Blood pressure is the force exerted by circulating blood on the walls of blood vessels. Arteries carry blood away from the heart under high pressure, which is why a severed artery spurts blood. In contrast, veins operate under lower pressure, leading to a slower, more passive leakage when they are severed.

Vascular Structure

The structure of arteries and veins differs significantly. Arteries have thicker, more muscular walls to withstand high pressure, while veins have thinner walls and valves to prevent backflow. This structural difference contributes to the distinct behavior of blood flow when each type of vessel is severed.

Hemodynamics

Hemodynamics is the study of blood flow and the forces involved in circulation. It explains how blood moves through the cardiovascular system and the impact of vessel type on blood flow dynamics. Understanding hemodynamics helps clarify why arteries spurt blood due to rapid pressure release, while veins leak more slowly.

Recommended video:

6:24

Hemodynamics

Related Practice

Textbook Question

Predict which would be more damaging to long-term survival: a blood clot lodged in the right coronary artery or one in the left coronary artery. Explain.

A birth defect called transposition of great vessels results in the pulmonary trunk emanating from the left ventricle and the aorta stemming from the right ventricle.

Predict the potential effects of this birth defect.

748

views

Textbook Question

Collagen vascular diseases weaken the collagen in the tunica externa of blood vessels. Predict the effects of such a disease.

932

views

Textbook Question

Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

Veins have smaller lumens, more elastic fibers, and more smooth muscle than arteries.

885

views