pathologic conditions, such as abscess, peritonitis,
appendicitis, pneumonia. Starvation reduces the
The white cells as seen under the microscope floating
in the blood plasma, appear as grayish cells, about
2To"o mcn m diameter, adhering to the walls of the
The cell structure appears as a homogeneous mass
containing numerous granules consisting of fat, pro-
tein, and carbohydrate. A nuclei can be seen by
the adding of a mild acid. They are ameboid, that is,
they show movements similar to those seen in the
amebse. As a result of this ameboid movement they
assume a different shape from time to time. White
cells have the properties of moving about and coming
in contact with bacteria, and disintegrated tissues, then
can be seen taking them into their substance and elimi-
nating them from the cell or digesting the invader.
They can by their movements slip through the wall
of the capillary vessel and appear in the adjacent
lymph spaces. This power of the white cell is best
appreciated in the early stages of inflammation when
the blood stream is always engorged with red and white
corpuscles; the latter can be seen passing into, through,
and outside the wall, and preparing to combat the
invading gerrn causing the trouble. This action of
the white corpuscles is called diapedesis.
The large and small lymphocytes originate in the
lymph glands, the solitary and combined glands of
the intestines, etc. They are carried into the blood
stream from these glands by means of the flowing
lymph. The polymorphonuclear, eosinophiles, baso-
philes, and leukocytes are derived from the bone-
marrow only. They reach the circulation by entering
the capillaries in the bone-marrow. Leukocytes dis-
appear by a process of dissolution. The period of
their life is unknown.
Function of White Cells. The polymorphonuclear,
large and small, lymphocytes possess the properties
of engaging and removing bacteria and broken-down
tissue. They attack and destroy more or less effec-
tively forms of intruding bacteria by surrounding,
and incorporating the tissue or bacterium and elimi-
nating them by a process of digestion. This swallowing
action of these white cells caused Professor Metchni-
koff to call them phagocytes, and the process as phago-
cytosis. Thus these scavengers aid the human body
in recovering from disease by combating and destroy-
ing the invading bacterium. White cells are supposed,
after breaking up, to contribute certain protein
222 THE CIRCULATORY APPARATUS
material to the blood plasma, which aids in the
coagulation of blood.
Blood Plaques. These are colorless disks con-
sisting of protoplasm. Their diameter is 1.5 to 3.5
micromillimeters. The number compared to the red
cells is 1 to 18 or 20. They are concerned mostly
with the coagulation of the blood, by their adhering
and forming irregular masses (Schultze), acting as a
nucleus for the fibrin filaments to spread from during
coagulation of the blood. They can only be seen
microscopically after subjecting the blood to treat-
ment with osmic acid.
Coagulation of Blood. Blood when freshly drawn from
a living body into a vessel is fluid. In a short time
it becomes thickened or viscid, this increase in con-
sistency becomes more marked .until the vessel con-
tains a dark reddish mass, resembling gelatin. Shortly
a few drops of fluid appear on the surface of the mass,
which gradually increases in amount, the vessel is
seen to contain a deposit of a firm, organized mass
the clot floating in a reddish-yellow fluid the
blood-serum. On examining a portion of the clot
microscopically, it will show threads of fibrin with
red and white corpuscles clinging to them.
The Clotting of Blood. This is supposed to be a
chemic phenomenon due to the action of a ferment,
derived from calcium chloride, and some authors
suggest leukocytes acting on the fibrinogen of the
blood plasma, and converting it into fibrin and thus
forming the nucleus of the clot. If blood is freshly
drawn into a vessel, then whipped with a bundle of
fine twigs for a few moments, the fibrin will be deposited
on these twigs as whitish threads. Blood treated in
this manner will not clot when left in the vessel; the
serum will be the only residue present. This blood,
treated as above, is called defibrinated.
1. Where is the pericardium found? Its function?
2. In which bony cavity of the body is the heart located?
3. W.hat is the position of the heart in the thoracic cavity?
4. What relation does the apex bear to the chest wall?
5. Can the beat of the heart be felt at any point on the chest
wall and where?
6 How many surfaces has the heart? Borders?
7. What are its dimensions? Weight, male and female?
8. What grooves can be seen on the external surface of the heart
9. How many chambers has the heart?
10. What divides the right side from the left? The auricles from
11. How many auricles are there? Ventricles?
12. What name is given to the opening between the auricle and
13 What is the lining membrane of the heart called?
14. What variety of cells are found in the endocardium?
15. What parts present themselves in the right auricle?
16. Name the small muscles found in the cavities of the right
and left ventricles.
17. Name the valves found in the right and left auriculoven-
tricular openings. The pulmonary artery and aorta.
18. How many leaflets has the mitral valve? Tricuspid valve?
19. What name is given to the cords extending between the
papillary muscles and margins of the mitral and tricuspid valves?
20. Give a brief description of the course of the blood through
the chambers of the heart?
21. What muscle transmits the contraction wave of the heart
muscle from the right auricle to the ventricular walls?
22. How is the cardiac cycle divided?
23. How long does the cycle of the heart last? How divided?
24. Give the normal beat of the heart per minute in an adult.
Fetus. First year of life. Third year. Eighth to fourteenth year.
25. At what point on the chest wall can the beat of the heart be
26. What causes the first sound of the heart? Second sound?
27. Describe briefly the fetal circulation.
28. Give the changes in the fetal circulation following birth.
29. Name the coats of an artery.
30. What variety of tissue renders arteries so elastic?
31. Why is the elasticity of the arterial wall so essential?
32. What causes arteries to contract?
33. What do you understand by the term vasa vasorum?
34. What are small arteries called? Veins?
35. What forms the walls of capillaries?
36. What are the functions of the capillaries?
37. How many coats form the wall of a vein?
38. Do some veins possess valves?
224 THE CIRCULATORY APPARATUS
39. What is the pulse?
40. Where is the pulse usually counted best?
41. What is the pulse due to?
42. What do you understand by a frequent or infrequent pulse?
Hard or soft? Tense or compressible? Large, full, or small?
43. Define blood pressure.
44. What do you understand by the term peripheral resistance?
45. How can you differentiate a hemorrhage from a vein or
46. What causes the difference in character of an arterial from
a venous hemorrhage?
47. What vessels carry the blood from the right ventricle of the
heart to the lungs?
48. How does the blood leave the left ventricle of the heart?
49. How does the blood from the lungs reach the left auricle of
50. What large vein empties the systemic blood into the right
auricle of the heart?
51. What are the divisions of the aorta.
52. Name the arteries supplying the following organs: stomach,
kidney, liver, heart, lungs, uterus, large bowel, appendix.
53. Give the location of the superficial and deep palmar arches
in the palm of the hand.
54. What are the branches of the transverse arch of the aorta?
55. What veins form the portal vein?
56. Name the organs which are drained by the portal vein and
57. What is the function of the blood?
58 Is blood alkaline or acid in reaction? What is the color of
arterial blood? Venous blood?
59. What causes the red color of arterial blood? The bluish
color of venous blood?
60. What are the constituents of blood?
61. What is the function of fibrinogen in blood?
62. Is sugar found in the blood? Fat?
63. What are the dimensions of a red cell?
64. Describe the appearance of blood under the microscope.
65. What is the function of the hemoglobin in the red cells?
66. What is the normal average number of red cells found in one
cubic millimeter of blood in the male? Female?
67. What is the normal average number of white cells found in a
cubic millimeter of blood?
68. What do you understand by the terms diapedesis, phago-
69. Describe the coagulation (clotting) of blood.
70. What are the functions of the white cells?
THE LYMPHATIC SYSTEM
THE lymphatic system includes primarily the
tissues or lymph spaces, the lymph and blood capil-
laries; secondarily, the lymphatic vessels, and lymph
nodes or lymphatic glands, and the veins which sub-
sequently receive the lymph through the large right
and thoracic ducts.
The lymphatic system is supposed to be a closed
system in relation with the tissues. The lymph reaches
the lymphatic vessels by transudation through the
endothelial lining of the vessels; this also occurs in
the serous membranes, and is not due to the lymph
passing by permanent openings between the cells
(stomata), as was once held.
The Tissues or Lymph Spaces. These are located
in practically every tissue and organ of the body.
They are found between cells (intercellular), around
bloodvessels (peri vascular), and around nerves (peri-
neural); these spaces are not lined by endothelial
cells; the cells are nourished as demonstrated above,
by a transudation through the capillary walls, and
the lymph -comes in contact with the cells in the
lymph spaces. The spaces in the cranial cavity, the
subdural and subarachnoid, also the serous cavities,
as the pericardial, pleural, peritoneal, and synovial
bursse, are lined by endothelial cells, and the lymph
transudes or passes through the membranes by
osmosis. The ventricles of the brain and the central
canal of the spinal cord contain lymph from the blood
capillaries of these parts, and communicate with the
226 THE LYMPHATIC SYSTEM
subarachnoid space (see Coverings of Brain and Spinal
Cord), whereupon it is taken up by the lymphatic
Lymph Capillaries. These are the connecting
vessels between the lymph spaces and the lymphatic
vessels proper. They are thin-walled vessels, which
consist of a single layer of endothelial cells. They
are arranged in plexuses interwoven with the blood
capillaries, and can be easily distinguished from them
by their larger size and irregular expansJons.
The blood capillaries, in relation with the lymph
capillaries, permit of a transudation of the nutritive
elements of the blood through their thin walls, and at
the same time assist in the reabsorption of a portion
of this transudate and waste products resulting from
The Lymphatic Vessels. They are arranged into
a superficial and deep set. The superficial set pass
just beneath the skin and follow the course of the
superficial veins, some pierce the fascia to communi-
cate with the deep set. These drain the surfaces of
the head, neck, trunk, and extremities. The deep
set follow the course of the deeper bloodvessels, and
drain the adjacent tissues. In the interior of the
trunk the lymphatics are found in the submucous
layer of the mucous membrane of the alimentary
canal and respiratory apparatus, also the genito-
urinary tract kidney, bladder, etc.
The lymphatic vessels are seen as a net-work of
minute vessels, larger than the capillary vessels, in
the above-mentioned tissues and organs. The lymph
is conveyed through these lymph capillaries to larger
.vessels called lymphatics, which pass to small glandular
bodies called lymph nodes or lymphatic glands.
The deep lymphatic vessels have the same origin
as the superficial set, but are fewer in number and
larger. They also drain into the lymph nodes.
The lymph vessels are composed of three coats:
THE LYMPHATIC NODES 227
The internal is of elastic fibers arranged lengthwise,
covered with a layer of endothelial cells; the middle
coat consists of white fibrous tissue arranged longi-
tudinally, with non-striated muscle and elastic fibers
arranged transversely; the external coat is practically
the same as the middle coat, except that the muscle
fibers are arranged longitudinally.
Lymph vessels possess valves, which are so close
together and so numerous as to appear as beads
upon the course of the vessels. They face toward
the larger vessels, are arranged in pairs, and are
formed from a reduplication of the vessel wall rein-
forced by white fibrous tissue from the middle coat.
The Lymph Nodes. They are small, solid, gland-
ular bodies found along the course of the lymphatic
vessels. They vary in size from a microscopic
mass of lymphoid tissue to an olive. Their color
when cut is pinkish, except in the bronchial nodes,
which are black, due to the absorption of foreign
particles of dust from the mucous membranes of
the respiratory tract; the nodes around the liver
(hepatic) are yellowish, due to the absorption of bile
pigments. The splenic lymph nodes are brown.
As the lymphatic vessels from the lymph spaces
approach a node they divide into numerous small
vessels called afferent vessels. The latter pierce the
capsule of the gland; devoid of their outer coat, they
enter the sinus beneath the capsule, termed the
subcapsular sinus, which communicates with a central
sinus. The lymph is "filtered within this node and is
collected by small vessels which unite beneath the
capsule and pierce it as a single efferent vessel. Upon
leaving the lymph node the efferent vessel is invested
by an external coat derived from the gland capsule.
The lymph continues to pass on until another set of
nodes are reached, when the same arrangement takes
place, and so on until the large lymphatic vessels
are reached, whereupon, through the thoracic ducts
228 THE LYMPHATIC SYSTEM
and right lymphatic duct, it is returned to the venous
circulation. While the lymph is in the nodes, newly
formed lymphocytes attack and destroy any bacteria
that are present.
Lymph nodes are divided into a superficial and
deep set, and usually found around bloodvessels and
embedded in fat. Occasionally they are single, but, as
a rule, are found arranged in chains. Bloodvessels and
nerves are plentiful. Besides these nodes, which will
be classified and described later, there are structures
allied to them tonsils and Peyer's patches of the
The Composition, Production, and Function of Lymph.
Lymph is a clear fluid found within the tissue spaces,
and termed intracellular lymph; and in the lymphatic
vessels called intravascular lymph. It is alkaline in
reaction, and has a specific gravity of 1.02 to 1.04.
When observed under the microscope, numbers of
leukocytes or white blood cells are seen. These consist
of a small amount of protoplasm in which can be
seen a nucleus. Lymph will clot, but not as actively
or as firmly as blood. The clotting is due to the
appearance of fibrin.
The Chemic Composition. This will vary, dependent
upon the portion of the body drained; however,
lymph obtained from the thoracic duct has been
found to contain, after chemic analysis, 34 to 41
per cent, of proteins (serum-albumin, fibrinogen),
0.046 to 0.13 per cent, of substances soluble in ether
(probably fat), 0.1 per cent, of sugar, and from 0.8
to 0.9 per cent, of inorganic salts, of which sodium
chloride (0.55 per cent.) and sodium carbonate (0.24
per cent.) are the most abundant (Munk). Small
amounts of calcium, potassium, and magnesium salts
are present; also both free oxygen and carbon dioxide;
urea in very small quantities. Lymph is similar in
composition to the plasma of the blood, only it does
not contain any red cells.
FUNCTIONS OF THE INTERCELLULAR LYMPH 229
Production of Lymph. This is still under discussion,
various theories being advanced, but none are abso-
lutely definite, nor is any accepted by physiologists as
the correct one. It is supposed to be formed by the
plasma of the blood passing through the thin-walled
capillaries into the small lymph spaces which exist
between the cells of the adjacent tissues; and another
theory is that this transudation is aided by an active
secretory action on the part of the endothelial cells
composing the capillary walls.
This passing or transudation of the nutritive material
and the white cells through the walls of the capillaries
is necessary in order to have the tissues receive the
elements essential for their nourishment, and to
combat, with the contained lymphocytes, any invading
germ, or to neutralize any toxin within the spaces.
The passage of the plasma or liquid nutritive element
of the blood through the capillary walls is based on
three factors: namely, osmosis, diffusion, and filtration.
(See standard works on physiology.)
The Functions of the Intercellular Lymph. The
intimate contact of the lymph with the tissue cells
of the body denotes that its function is to furnish
those cells with nutritive elements essential to their
growth, repair, and functional activity, and to receive
from those cells the products resulting from disintegra-
tion or tissue waste as a result of body metabolism.
In order to have the lymph in relation with the
tissue cells retain a certain composition, which is con-
stantly being reduced by the absorption of the waste
products into the lymph vessels and blood, it is
necessary that the lymph be renewed as rapidly as
consumed, and the waste material removed as pro-
duced. Should one of these conditions fail the nutri-
tive elements of the lymph would be reduced, and
consequently destroy the vitality of the tissues.
The formation of lymph is a continuous phenomena
and more is formed than is essential to the needs of
THE LYMPHATIC SYSTEM
the tissues to maintain their normal activities. Should
the lymph be allowed to accumulate, it would lead
UPPER END OF
Thoracic duct, azygos, and intercostal veins.- (Testut.)
THE THORACIC DUCTS 231
to a condition of edema and an interference with the
functional activities of the tissues. But in health,
before this condition of congestion is permitted, the
lymphatic vessels collect the excess volume and
carry it into the thoracic ducts, which convey it into
the venous system. 1
The Thoracic Ducts. These are two in number, the
right and a common trunk. They drain all the smaller
lymphatic vessels of the body and open into the veins.
The thoracic duct, or common trunk, drains all the
vessels of the body, except the right side of the head
and neck, the right upper extremity, the right side of
the lung and its pleura, the heart and pericardium, and
the convex surface of the liver; the latter are drained
by the right thoracic duct. The common trunk begins
as the receptacuium chyli, situated opposite the second
and third lumbar vertebra behind the peritoneum.
The duct is 15 to 18 inches in length. It extends from
the second lumbar vertebra to the root of the neck,
where it empties into the angle of junction of the
subclavian and internal jugular veins. It passes
through the aortic opening in the diaphragm between
the aorta and the azygos vein. In the thorax it lies
between the esophagus and aorta on the thoracic ver-
tebra; upon reaching the fourth thoracic vertebra it
turns toward the left and passes behind the arch of
the aorta and at the seventh cervical vertebra empties
into the veins as above.
The right duct is only about one-half inch in length
and opens into the junction of the internal and sub-
clavian veins in the right side.
1 The description of the systemic lymphatic vessels and glands
are not included, as they are not considered essential to a nurse's
232 THE LYMPHATIC SYSTEM
1. What structures are included under the lymphatic system?
2. How does the lymph reach the lymphatic vessels?
3. Where are lymph spaces found in the tissues of the body?
4. Where are the superficial set of lymphatic vessels located?
5. In which layer of a mucous membrane are the lymphatic
vessels usually found?
6. Into what structure does the lymphatic vessel drain?
7. Name the coats of a lymphatic vessel.
8. Do lymph vessels possess valves?
9. Describe a lymph node or gland.
10. What are afferent, efferent lymphatic vessels?
11. Where are lymph glands usually found?
12. What is the function of a lymph capillary?
13. What is the relation and function of blood capillaries to the
14. Give the composition of lymph.
15. How is lymph produced generally?
16. Is lymph a necessary fluid as regards the nourishment of the
17. What is the function of the thoracic ducts?
18. Where is the receptaculum chyli located?
19. What portions of the body are drained of lymph by the right
thoracic duct? The left or common?
20. Into which vein does the right thoracic duct empty? The
THE RESPIRATORY APPARATUS
THE respiratory apparatus consists of those organs
which receive and return the air breathed through
the nose, mouth, and pharynx, and convey it in a
system of closed tubes and cavities to the termination
of the lungs, where it comes in contact with the
capillaries of the blood, which permit, owing to their
thin walls and the lining membrane of the air cells of
the lungs a gaseous interchange between the carbon
dioxide and other waste materials of the blood and
the oxygen of the air breathed during the act of
THE ORGANS OF RESPIRATION
In man the respiratory apparatus is described
under the following: Larynx, Trachea, Bronchi, and
The organs of respiration are located as follows:
The larynx and beginning of the trachea in the neck,
the bronchi and lungs within the thorax.
The Nasal Cavities. These are the proper channels
for the air to pass through. However, the mouth can
be used as desired by the individual, as is usually
employed by persons suffering from any nasal obstruc-
tion or a deficient amount of air reaching the lungs,
due to heart, lung, throat trouble, or changes in the
blood which compel forced or labored breathing
dyspnea. The air as it passes through the nasal
234 THE RESPIRATORY APPARATUS
cavities is warmed by coming in contact with the
highly vascularized mucous membrane lining them,
and thus is prevented from reaching the lungs at a
low temperature, which would cause their congestion
and be dangerous to health. The air also passes
through the pharynx to reach the larynx.
The Larynx. The larynx is the organ of the voice,
and is placed at the upper and forepart of the neck,
between the trachea and base of the tongue. It com-
municates above with the laryngopharynx, below with
Relations. It has on each side of it the carotid vessels,
and behind it the pharynx. In front are the pretra-
cheal portions of the cervical fascia and the upper end
of the thyroid gland, and on each side the sterno-
hyoid and thyroid and the thyrohyoid muscles. It
consists of various cartilages held together by liga-
ments, and is lined internally by mucous membrane,
continuous with that of the pharynx above and the
The cartilages are nine: Three pairs, the arytenoid,
cornicula laryngis, and cuneiform; and three single,
the thyroid, cricoid, and epiglottis.
The thyroid cartilage is the largest, and consists of
two lateral parts or alse uniting in front to form the
projection of the Adam's apple (pomum Adami).
This is subcutaneous, more distinct above and in the
male. Internally it is smooth, and in the angle the
epiglottis, true and false vocal cords, and the thyro-
arytenoid and thyro-epiglottidean muscles are attached.
The upper border is concavoconvex, and in front is
notched over the pomum Adami, giving attachment
throughout to the thyrohyoid membrane. The lower
border is joined to the cricoid cartilage by the middle
portion of the cricothyroid membrane; and on either
side, affords attachment to the cricothyroid muscle.
The posterior borders end in the upper and lower
cornua (horns); to the upper are attached the lateral
THE ORGANS OF RESPIRATION