Chapter 11 – Blood Vessels:The Structure & Function of Blood Vessels Flashcards
Vascular disorders—and their downstream sequelae—are responsible for more morbidity and
mortality than any other category of human disease.
The most clinically significant lesions typically involve arteries only.
T or F
FALSE
Although the most clinically significant
lesions typically involve arteries, venous diseases also occur.
Vascular pathology results in
disease via two principal mechanisms:
- (1) Narrowing (stenosis) or complete obstruction of vessel lumens, either progressively (e.g., by atherosclerosis) or precipitously (e.g., by thrombosis or embolism); and
- (2) weakening of vessel walls, leading to dilation or rupture.
The general architecture and cellular composition of blood vessels are not the same throughout the
cardiovascular system.
T or F
FALSE
However, certain features of the vasculature vary with and reflect
distinct functional requirements at different locations ( Fig. 11-1 ). To withstand the pulsatile flow
and higher blood pressures in arteries, arterial walls are generally thicker than the walls of
veins. Arterial wall thickness gradually diminishes as the vessels become smaller, but the ratio
of wall thickness to lumen diameter becomes greater
FIGURE 11-1 Regional specializations of the vasculature. Although the basic organization of
the vasculature is constant, the thickness and composition of the various layers differ
according to hemodynamic forces and tissue requirements
What are the basic constituents of the walls of blood vessels ?
- endothelial cells and smooth muscle cells, and
- extracellular matrix (ECM), including elastin, collagen, and glycosoaminoglycans
What are the three concentric layer of the blood vessel?
- intima,
- media, and
- adventitia—
are most clearly defined in the larger
vessels, particularly arteries.
In normal arteries, what is the appearance of intima?
In normal arteries, the intima consists of a single layer of
endothelial cells with minimal underlying subendothelial connective tissue
What separates the intima of a bv from the media?
a dense elastic membrane called the internal elastic lamina.
How does the smooth muscle cell layer of the media near the vessel lumen receive oxygen and nurtrientS?
direct diffusion
from the vessel lumen, facilitated by holes in the internal elastic membrane.
Since diffusion
from the lumen is inadequate for the outer portions of the media in large and medium-sized vessels, therefore how are they nourished?
are nourished by small arterioles arising from outside the vessel
(called vasa vasorum, literally “vessels of the vessels”) coursing into the outer one half to two
thirds of the media.
The outer limit of the media of most arteries is a what?
is a well-defined external elastic lamina.
What is external to the media?
adventitia,
consisting of connective tissue with nerve
fibers and the vasa vasorum.
Based on their size and structural features, arteries are divided into three types:
- (1) large or elastic arteries
- (2) medium-sized or muscular arteries,
- (3) small arteries
What are your large or elastic arteries?
- including the aorta,
- its large branches (particularly the innominate, subclavian, common carotid, and iliac),
- and pulmonary arteries;
What are your medium-sized or muscular arteries?
medium-sized or muscular arteries,
comprising other branches of the aorta (e.g., coronary and renal arteries);
