SECTION E CLINICAL TERMS
SECTION E REVIEW QUESTIONS
1. Draw a ﬂ ow diagram illustrating the reﬂ ex compensation for
2. What happens to plasma volume and interstitial ﬂ
following a hemorrhage?
3. What causes hypotension during a severe allergic response?
4. How does gravity inﬂ uence effective blood volume?
5. Describe the role of the skeletal muscle pump in decreasing
capillary ﬁ ltration.
6. List the directional changes that occur during exercise for all
relevant cardiovascular variables. What are the speciﬁ c efferent
mechanisms that bring about these changes?
7. What factors enhance venous return during exercise?
8. Diagram the control of autonomic outﬂ ow during exercise.
9. What is the limiting cardiovascular factor in endurance exercise?
10. What changes in cardiac function occur at rest and during
exercise as a result of endurance training?
11. What is the abnormality in most cases of established hypertension?
12. State how ﬂ uid retention can help restore stroke volume in
13. How does heart failure lead to edema in the pulmonary and
systemic vascular beds?
14. Name the major risk factors for atherosclerosis.
15. Describe changes in lifestyle that may help prevent coronary
16. List some ways that coronary artery disease can be treated.
automatic electronic deﬁ
calcium channel blocker
cardiac inotropic drug
congestive heart failure
coronary artery disease
left ventricular hypertrophy
transient ischemic attack
Blood and Hemostasis
Blood was deﬁ ned earlier as a mixture of cellular components
suspended in a ﬂ uid called plasma. In this section we will take
a more detailed look at blood cells and plasma, and then dis-
cuss the complex mechanisms that prevent blood loss follow-
Plasma consists of a large number of organic and inorganic sub-
stances dissolved in water. Inside this book’s back cover are listed
substances dissolved in plasma, and their typical concentrations.
constitute most of the p
solutes, by weight. Their role in exerting an osmotic pressure
that favors the absorption of extracellular ﬂ
uid into capillaries
was described earlier. They can be classiﬁ ed into three broad
ﬁ rst two have many overlapping functions, which are dis-
cussed in relevant sections throughout the book. Fibrinogen
functions in clotting, discussed in detail in the latter part
of this section.
is plasma with ﬁ brinogen and other
proteins involved in clotting removed as a result of clotting.
The albumins are the most abundant of the three plasma
protein groups and are synthesized by the liver. Cells nor-
mally do not take up plasma proteins; cells use plasma amino
acids, not plasma proteins, to make their own proteins. Thus,
plasma proteins must be viewed differently from most of the
other organic constituents of plasma, which use the plasma as
a medium for transport to and from cells. In contrast, most
plasma proteins perform their functions in the plasma itself or
in the interstitial ﬂ
In addition to the organic solutes, including proteins,
nutrients, metabolic waste products, and hormones, plasma
contains a variety of mineral electrolytes. These ions contrib-
ute much less to the
of plasma than do the proteins,
but in most cases they have much higher
This is because molarity is a measure not of weight, but of
number of molecules per unit volume. Thus, there are many
more ions than protein molecules, but the protein molecules
are so large that a very small number of them greatly out-
weighs the much larger number of ions.
The Blood Cells
The major functions of erythrocytes are to carry oxygen taken
in by the lungs and carbon dioxide produced by the cells.
Erythrocytes contain large amounts of the protein
with which oxygen and, to a lesser extent, carbon diox-
ide reversibly combine. Oxygen binds to iron atoms (Fe
the hemoglobin molecules. The average concentration of