15

Question 1

The first two lines of defense are

specific
nonspecific

Answer 1

nonspecific

Question 2

these are
ways in which the body attempts to destroy all types of
substances that are foreign to it, including pathogens.

Answer 2

The first two lines of defense

Question 3

what is The third line of defense,

Answer 3

the immune response, is very specific.

Question 4

special proteins called ____ are usually
produced in the body in response to the presence of foreign
substances.

Answer 4

antibodies

Question 5

These foreign substances are called __
because they stimulate the production of specific
antibodies;

Answer 5

antigens

Question 6

antigens means

Answer 6

“antibody-generating”

Question 7

are general and
serve to protect the body against many harmful substances.

Answer 7

Nonspecific host defense mechanisms

Question 8

Although certain helminth infections ______ are acquired by penetration of the skin by
parasites

Answer 8

(e.g., hookworm infection and schistosomiasis)

Question 8

the third line of defense as

Answer 8

acquired immune responses

Question 9

serves as a
nonspecific host defense mechanism by flushing organisms
from pores and the surface of the skin

Answer 9

Perspiration

Question 9

They refer to the second line of defense as

Answer 9

innate immune responses

Question 9

Also, the acidity
_____ and temperature _____ of the skin inhibit the
growth of pathogens.

Answer 9

(pH ∼5.0). (<37°C),

Question 10

The oily sebum that is produced by
sebaceous glands in the skin contains ___, which are
toxic to some pathogens.

Answer 10

fatty acid

Question 10

is a protein that binds iron, a
mineral that is required by all pathogens.

Answer 10

Lactoferrin

Question 11

serves as a nonspecific host defense
mechanism by trapping pathogens.

Answer 11

Sticky mucus

Question 11

Perspiration also
contains the enzyme,_____ which degrades
peptidoglycan in bacterial cell walls (especially Grampositive bacteria).

Answer 11

lysozyme,

Question 11

As previously mentioned,
lysozyme destroys bacterial cell walls by degrading their

Answer 11

peptidoglycan

Question 12

is an enzyme that produces superoxide
radicals, highly reactive forms of oxygen, which are toxic to
bacteria.

Answer 12

Lactoperoxidase

Question 13

To a certain extent, the following factors protect the
gastrointestinal (GI) tract from bacterial colonization and
are, therefore, considered to be nonspecific host defense
mechanisms:

Answer 13

Digestive enzymes
Acidity of the stomach (pH ∼1.5)
Alkalinity of the intestines

Question 14

, which is secreted from the liver into the small
intestine, lowers the surface tension and causes chemical
changes in bacterial cell walls and membranes that make
bacteria easier to digest.

Answer 14

Bile

Question 14

Sticky mucus
It also contains toxic
substances, such as

Answer 14

lysozyme, lactoferrin, and
lactoperoxidase.

Question 15

and the
expulsion of feces serve to remove bacteria from the
intestine.

Answer 15

Peristalsis

Question 16

Bacteria make up about

Answer 16

30% to 50% of feces.

Question 17

Conditions that obstruct urine flow

Answer 17

(e.g., benign prostatic hyperplasiaa) also increase the
chances of developing cystitis.

Question 18

serve to remove pathogens from the GI tract and urinary tract, respectively.

Answer 18

Peristalsis and urination

Question 19

When indigenous microbiota prevents the establishment of arriving pathogens, it is known as

Answer 19

microbial antagonism.

Question 20

This overgrowth or “population explosion” of organisms is called a

Answer 20

superinfection

Question 21

A superinfection of Candida albicans yeasts in the vagina may lead to the condition known as

Answer 21

yeast vaginitis.

Question 22

A superinfection of Clostridium difficile bacteria in the colon may lead to

Answer 22

C. difficile–associated diseases such as antibiotic-associated diarrhea and pseudomembranous colitis.

Question 23

Some bacteria produce proteins that kill other bacteria; collectively, these antibacterial substances are known as

Answer 23

bacteriocins

Question 24

Some bacteria produce proteins that kill other bacteria; collectively, these antibacterial substances are known as _____.

Answer 24

bacteriocins

Question 25

what is a glycoprotein synthesized in the liver, has a high affinity for iron.

Answer 25

Transferrin,

Question 26

Substances that stimulate the production of fever are called

Answer 26

pyrogens or pyrogenic substances.

Question 27

what is that is produced by certain white blood cells, is an example of an endogenous pyrogen

Answer 27

Interleukin 1 (IL1), a cytokine

Question 28

these are small, antiviral proteins produced by virus-infected cells.

Answer 28

Interferons

Question 29

The three known types of interferon, referred to as

Answer 29

alpha (α), beta (β), and gamma (γ) interferons,

Question 30

α-Interferon is produced by

Answer 30

B lymphocytes (B cells), monocytes, and macrophages;

Question 31

but rather a group of approximately 30 different proteins (including 9 proteins designated as C1 through C9) that are found in normal blood plasma. These proteins make up what is called

Answer 31

“the complement system”—

Question 31

β-interferon, by

Answer 31

fibroblasts and other virus-infected cells

Question 32

γ-interferon, by activated

Answer 32

T lymphocytes (T cells) and natural killer cells

Question 33

The proteins of the complement system, sometimes collectively referred to as complement components, interact with each other in a stepwise manner, known as the

Answer 33

complement cascade.

Question 34

is a process by which phagocytosis is facilitated by the deposition of opsonins, such as antibodies or certain complement fragments, onto the surface of particles or cells.

Answer 34

Opsonization

Question 35

One of the products formed during the complement cascade, called

Answer 35

C3b, is an opsonin.

Question 36

Plasma levels of molecules collectively referred to as ______ increase rapidly in response to infection, inflammation, and tissue injury.

Answer 36

acutephase proteins

Question 37

They serve as host defense mechanisms by enhancing resistance to infection and promoting the repair of damaged tissue.

Answer 37

acutephase proteins

Question 38

are chemical mediators that are released from many different types of cells in the human body.

Answer 38

Cytokines are

Question 39

They enable cells to communicate with each other. They act as chemical messengers both within the immune system (discussed in Chapter 16) and between the immune system and other systems of the body

Answer 39

Cytokines

Question 40

An increase in the diameter of capillaries _____), which increases blood flow to the site

Answer 40

(vasodilation

Question 41

The three major events in acute inflammation are

Answer 41

vasodilation, increased permeability of the capillaries, and escape of leukocytes from the capillaries.

Question 42

The accumulation of fluid, cells, and cellular debris at the inflammation site is referred to as an

Answer 42

inflammatory exudate

Question 43

If the exudate is thick and greenish yellow, containing many live and dead leukocytes, it is known as a ____ or pus

Answer 43

purulent exudate

Question 44

Although most pus is greenish yellow, the exudate is often bluish green in infections caused by

Answer 44

Pseudomonas aeruginosa

Question 45

The two most important groups of phagocytes in the human body are_____ ; they are sometimes called “professional phagocytes” because phagocytosis is their major function.

Answer 45

macrophages and neutrophils

Question 46

serve as a “cleanup crew” to rid the body of unwanted and often harmful substances, such as dead cells, unused cellular secretions, debris, and microbes.

Answer 46

Macrophages

Question 47

The three major categories of leukocytes found in blood are

Answer 47

monocytes, lymphocytes, and granulocytes.

Question 48

are named for the prominent cytoplasmic granules that they possess.

Answer 48

Granulocytes

Question 49

Phagocytic granulocytes include

Answer 49

neutrophils and eosinophils.

Question 50

also known as polymorphonuclear cells, polys, and PMNs) are much more efficient at phagocytosis than eosinophils

Answer 50

Neutrophils (

Question 51

An abnormally high number of eosinophils in the peripheral bloodstream is known as

Answer 51

eosinophilia.

Question 52

a third type of granulocyte, are also involved in allergic and inflammatory reactions, although they are not phagocytes.

Answer 52

Basophils

Question 53

what macrophages are those that leave the bloodstream and migrate to infected areas are called

Answer 53

wandering macrophages

Question 54

(also known as histocytes or histiocytes) remain within tissues and organs and serve to trap foreign debris.

Answer 54

Fixed macrophages

Question 55

Macrophages are extremely efficient phagocytes. They are found in tissues of the

Answer 55

reticuloendothelial system (RES

Question 56

Four Steps in Phagocytosis

Answer 56

Chemotaxis Attachment Ingestion . Digestion