Lymphatic System I

Question 1

The lymphatic system collects _____ and _____ from interstitial regions and returns them
to the blood.

Answer 1

fluid; proteins

Question 2

Lymphatic capillaries are extremely _____ and they can therefore collect not only fluid but
also proteins and even cells.

Answer 2

porous

Question 3

Specialized lymphatic capillaries participate in digestion by absorbing _____.

Answer 3

lipids and lipid-soluble

substances

Question 4

. One of the major functions of the lymphatic system is to _____ the interstitial fluid.

Answer 4

purify

Question 5

One of the lymphatic system’s tasks is to destroy cells which are not normally found in the
body, but sometimes it is unsuccessful in destroying _____; it is not uncommon for these
cells to invade lymphatic tissue and begin to grow.

Answer 5

cancer cells

Question 6

The fluid in the lymphatic system is called _____.

Answer 6

lymph

Question 7

About 3 liters per _____ travels through the lymphatic system, compared with 5 liters per
_____ through the circulatory system.

Answer 7

day; minute

Question 8

Lymph can flow in only one direction because of _____ in the lymphatic vessels.

Answer 8

one-way valves

Question 9

Lymph is primarily propelled toward the site where it is returned to the blood by _____,
although _____ in the vessel walls also participates.

Answer 9

the motions of the body;

smooth muscle

Question 10

The smallest lymphatic vessels are called _____ and are essentially microscopic, dead-end tubes.

Answer 10

lymphatic capillaries

Question 11

Endothelial cells that make up the lymph capillaries overlap loosely to form _____.

Answer 11

one-way valves

Question 12

Increased fluid pressure in regions surrounding lymph capillaries causes the overlapping
regions of the cells of the capillaries to _____.

Answer 12

separate

Question 13

High pressures in the lymph fluid within the lymphatic capillaries cause the overlapping
regions of the cells of which the capillaries are made to _____.

Answer 13

press together

Question 14

Lymphatic capillaries are prevented from collapsing as tissue fluid increases by anchoring
_____ attached to the endothelial cells of the vessel.

Answer 14

collagen filaments

Question 15

_____ are specialized lymph capillaries in the _____ of the small intestine.

Answer 15

Lacteals; villi

Question 16

Most lymph in the body appears _____, but that in lacteals (called _____) is creamy white
due to the high concentration of lipids.

Answer 16

clear; chyle

Question 17

When several lymph capillaries merge, they form a(n) _____.

Answer 17

lymphatic collecting vessel

Question 18

The walls of lymphatic collecting vessels, like those of blood vessels, have _____ tunics.

Answer 18

three

Question 19

When lymphatic collecting vessels merge, they form _____.

Answer 19

lymphatic trunks

Question 20

There are nine major lymphatic trunks: two each of the _____, _____, _____ and _____
trunks, and one of the _____ trunk.

Answer 20

lumbar; jugular; subclavian;

bronchomediastinal; intestinal

Question 21

When lymphatic trunks merge, they form the largest lymphatic vessels in the body, the
_____. (There are only _____ of these in the body; in some individuals, the
_____ one is absent and several trunks drain into the venous system directly.)

Answer 21

lymphatic ducts; two; right

Question 22

Lymph from the legs, several abdominal organs and the lower torso enters the left
lymphatic (a.k.a. thoracic) duct via a dilated sac called the _____.

Answer 22

cisterna chyli

Question 23

The left and right lymphatic ducts drain into the left and right _____ veins, at their
intersection with the _____.

Answer 23

subclavian; jugular veins

Question 24

Blood is prevented from entering the lymphatic ducts by the presence of _____.

Answer 24

one-way valves

Question 25

The _____ collects lymph from the bulk of the body, including one entire side of the body
and regions on the opposite side below the thorax.

Answer 25

left thoracic lymphatic duct

Question 26

The _____ collects lymph only from a small portion of one side of the body.

Answer 26

right lymphatic duct

Question 27

One major class of white blood cells, the \_\_\_\_\_, take their name from their presence in 
the lymphatic system.

Answer 27

lymphocytes

Question 28

One major class of lymphocytes, the \_\_\_\_\_, are formed in the bone marrow, but mature in 
the thymus gland.

Answer 28

T-cells or T lymphocytes

Question 29

_____ attack cells in the body that are not recognized as normal members of the body’s
cellular community.

Answer 29

T-cells or T lymphocytes

Question 30

_____ are a type of blood cell that develops and matures in the bone marrow before
moving to the lymphatic system.

Answer 30

B-cells or B lymphocytes

Question 31

A(n) _____ is any large molecule with a unique shape which can be recognized by the
immune system.

Answer 31

antigen

Question 32

. When _____ encounter an antigen, they divide to form plasma cells and memory cells.

Answer 32

B-cells or B lymphocytes

Question 33

_____ release antibodies which bind to antigens.

Answer 33

Plasma cells

Question 34

_____ circulate in the lymph and blood for many years, and respond rapidly if an antigen
encountered in the past is again encountered.

Answer 34

Memory cells

Question 35

Many _____, cells that are descended from monocytes and which engulf microbes and
debris, are found in the lymph fluid.

Answer 35

macrophages

Question 36

The lymphatic system’s supporting structure is provided largely by _____ cells and the
fibers they produce.

Answer 36

reticular

Question 37

Lymphatic tissues are classified depending on the _____ and whether or not it is
surrounded by a(n) _____.

Answer 37

distribution of the cells; capsule

Question 38

Lymphatic tissues in the _____ (a vascular layer of connective tissue under the basement
membrane of epithelium, particularly mucosal epithelium), in general, are referred to as
_____.

Answer 38

lamina propria; mucosa-associated lymphoid tissue (MALT)

Question 39

When MALT is found in the gastrointestinal tract, it is referred to as _____.

Answer 39

gut associated lymphoid tissue

GALT

Question 40

_____ is lymphatic tissue in which lymphocytes and macrophages are only loosely
associated with the reticular fiber network, and which is not clearly separated from
surrounding tissues.

Answer 40

Diffuse lymphatic tissue