Deck 15: Innate Immunity

Question 1

Fever is beneficial during viral infection because the higher temperature

A) increases the effectiveness of interferons.
B) results in virus being shed in sweat.
C) prevents viral infection of fibroblasts.
D) denatures viral proteins.
E) increases vasodilation, bringing more leukocytes to the site of infection.

Answer 1

A

Question 2

TLRs are

A) phagocyte receptors that detect PAMPs.
B) present in intact skin, sebum, tears, etc.
C) the coatings of pathogens by complement.
D) molecules that damage cells, resulting in cell lysis.
E) nonspecific leukocytes that secrete toxins onto the surface of virally infected cells.

Answer 2

A

Question 3

Which complement protein is the key to activating the alternative pathway of complement activation?

A) C1
B) C2
C) C3
D) C4
E) C5

Answer 3

C

Question 4

Which of the following statements regarding phagocyte recognition of pathogens is true?

A) TLRs on the surface of microbes trigger the accumulation of opsonins.
B) MACs on the surface of microbes are detected by NOD proteins.
C) Lectins on the surface of microbes are bound by chemokine receptors.
D) NOD proteins on the surface of microbes are detected by TLRs.
E) TLRs in the phagocyte cytoplasmic membrane bind surface structures of microbes.

Question 5

Which of the following contributes to protecting the eyes from microbial invasion?

A) Tears mechanically flush particles from the eyes.
B) Tears and mucus combine to trap microbes and remove them.
C) A mucus layer traps and removes microbes.
D) Tears contain lysozyme and salt and mechanically flush particles from the eyes.
E) Tears contain lysozyme and salt.

Question 6

Which cell becomes a macrophage when leaving the bloodstream?

A) basophil
B) eosinophil
C) monocyte
D) neutrophil
E) lymphocyte

Question 7

Which of the following areas of the body have mucous membranes?

A) mouth, nasal cavity, and urinary system
B) mouth and nasal cavity
C) urinary system
D) nasal cavity
E) mouth

Question 8

Which of the following leukocyte functions do macrophages carry out?

A) secretion of leukotrienes
B) phagocytosis of pathogens and debris
C) release of alpha interferon
D) phagocytosis of pathogens and production of NETs
E) phagocytosis of pathogens and secretion of alpha interferons and leukotrienes

Question 9

Which of the following is the best definition of "microbial antagonism"?

A) the presence of resident bacteria on the surface of the body and in cavities that connect to the surface
B) the presence of normal microbiota that protect the body by competing with pathogens in a variety of ways to prevent pathogens from invading the body
C) the ability of microbiota to mutate into pathogens
D) the presence of pathogens on the surface of the skin, which will invade the body through abrasions
E) the presence of normal microbiota that can become pathogens under certain conditions

Question 10

Which of the following statements regarding the surface of the skin is false?

A) It has goblet cells.
B) It is salty.
C) It is acidic.
D) It has normal microbiota.
E) It has sebum as a coating.

Question 11

The play a role in preventing neoplastic cells from progressing to cancer.

A) NK cells
B) neutrophils
C) eosinophils
D) basophils
E) mast cells

Question 12

Which of the following iron- binding proteins is NOT part of the body's iron storage and transport system?

A) lactoferrin
B) siderophores
C) gastroferritin
D) transferrin
E) ferritin

Question 13

Mucous membranes are quite thin and fragile. How can such delicate tissue provide defense against microbial invaders?

A) The mucus is a physical trap that contains a variety of antimicrobial chemicals.
B) The mucus contains a variety of antimicrobial chemicals and molecules.
C) Both the mucus and the outer layer of cells are shed frequently.
D) The mucus secreted by the mucous membrane physically traps microbes.
E) The mucus physically traps microbes, contains a variety of antimicrobial chemicals, and is shed constantly, along with the outermost layer of cells.

Question 14

Wandering macrophages recognize microorganisms by means of

A) TLRs.
B) lectins and C3 protein.
C) NOD proteins.
D) lectins.
E) both TLRs and NOD proteins.

Question 15

Which of the following statements about eosinophil function is true?

A) They secrete toxins onto virally infected cells.
B) They produce defensins.
C) They identify and spare normal cells.
D) They are involved in the removal of neoplastic cells.
E) They attach to the surface of parasitic helminths and produce toxins that kill the parasite.

Question 16

Alpha and beta interferons

A) produce active antiviral proteins (AVPs) that coat the surface of healthy cells and prevent the attachment of pathogenic viruses.
B) help protect virus- infected cells from the effects of the pathogen.
C) protect the cells that secrete them from being invaded by a virus.
D) are produced by infected fibroblasts and macrophages.
E) produce no adverse effects in the body.

Question 17

Which of the following is the key difference in the roles of the classical and alternative pathways of the complement system?

A) the effectiveness in killing Gram- negative bacteria
B) production of chemotactic factors
C) triggering inflammation
D) the range of microbe types that can be targeted
E) the formation of MACs

Question 18

The complement cascade and its by- products contribute to

A) triggering release of interferons.
B) triggering inflammation.
C) attracting phagocytes to sites of infection.
D) triggering inflammation and release of interferons.
E) both triggering inflammation and attracting phagocytes to sites of infection.

Question 19

Which of the following leukocytes have granules in their cytoplasm that stain blue with methylene blue?

A) basophils
B) eosinophils
C) monocytes
D) neutrophils
E) lymphocytes

Question 20

Which of the following are phagocytic cells found in the epidermis?

A) microglia
B) natural killer lymphocytes
C) neutrophils
D) wandering macrophages
E) dendritic cells

Question 21

Protection from infection known as species resistance is a result of

A) the absence of receptors required for microbial attachment.
B) the salty, acidic condition of normal skin.
C) the presence of phagocytes in the tissues.
D) the lack of suitable environment in the body.
E) both the absence of necessary receptors and lack of suitable environment in the body.

Question 22

Opsonization is

A) the sticking of monocytes to the wall of the blood vessels at the site of infection.
B) damage resulting in cell lysis.
C) phagocyte receptors detecting PAMPs.
D) the coating of a pathogen by complement to facilitate phagocytosis.
E) nonspecific leukocyte secretion of toxins onto the surface of virally infected cells.

Question 23

Which of the following is NOT an example of a walled- off site of infection that contains a fluid made of dead and dying tissue cells, leukocytes, and pathogens?

A) a boil
B) a pustule
C) an abscess
D) a pimple
E) a tumor

Question 24

Which of the following cells increase in number during a helminth infection?

A) macrophages
B) neutrophils
C) basophils
D) eosinophils
E) lymphocytes

Question 25

Which of the following substances is responsible for the edema associated with inflammation?

A) interferon
B) defensin
C) leukotrienes
D) histamine
E) both leukotrienes and histamine

Question 26

Which of the following statements concerning the alternative complement system is true?

A) It is more efficient than the classical pathway.
B) It is not useful in the early stages of fungal infection.
C) Its activation is independent of antibodies.
D) It works best on Gram- positive bacteria.
E) It plays a very significant role in the elimination of parasitic helminths.

Question 27

Structures and products of pathogens that immune cells detect and respond to are called

A) prostaglandins.
B) NODs.
C) PAMPs.
D) TLRs.
E) leukotrienes.

Question 28

Which of the following statements is true of eosinophils?

A) They secrete toxins onto the surface of helminth parasites.
B) They are in intact skin, sebum, tears, etc.
C) They release prostaglandins and leukotrienes in response to microbes.
D) They produce the coating of a pathogen by complement.
E) They decline during allergic reaction.

Question 29

Mucus and sweat contain which damage and kill bacteria.

A) salts
B) NOD proteins
C) antimicrobial peptides
D) antibodies
E) complement fragments

Question 30

Lectins specific for mannose can lead to attack on fungi by

A) NK cells.
B) basophils.
C) macrophages.
D) neutrophils.
E) complement.

Question 31

How does aspirin act to decrease the symptoms of inflammation?

A) It prevents complement activation.
B) It interferes with the action of interferons.
C) It blocks the release of histamine.
D) It acts as an antiprostaglandin.
E) It is an antitoxoid for most microbial toxins.

Question 32

Receptors known as NOD proteins detect molecules associated with microbes

A) on the surface of cells.
B) in the extracellular fluid.
C) in the phagolysosome.
D) in the cytoplasm.
E) in the cytoplasmic membrane.

Question 33

The phenomenon known as chemotaxis is defined as

A) the release of prostaglandins and leukotrienes in response to microbes.
B) the coating of a pathogen by complement.
C) an increase in allergies and helminth infection.
D) the squeezing of cells through the lining of capillaries.
E) the movement of a cell toward or away from a chemical stimulus.

Question 34

Response to specific pathogens that can improve with subsequent exposure is

A) the third line of defense.
B) the second line of defense.
C) microbial antagonism.
D) innate immunity.
E) the first line of defense.

Question 35

First line of defense may be described as

A) the release of prostaglandins and leukotrienes in response to microbes.
B) damage resulting in cell lysis.
C) intact skin, mucous membranes, sebum, tears, and so forth.
D) nonspecific leukocytes that secrete toxins onto the surface of virally infected cells.
E) the coating of a pathogen by complement.

Question 36

Which of the following characteristics is shared by the skin and mucous membranes?

A) They both have cilia.
B) Sebum may be present.
C) They are both constantly shedding and replacing cells.
D) Lysozymes are always present.
E) The outer layers are composed of dead cells.

Question 37

The leukocytes called natural killer lymphocytes

A) respond to the coating of a pathogen by complement.
B) release prostaglandins and leukotrienes in response to microbes.
C) increase in allergies and helminth infection.
D) are nonspecific leukocytes that secrete toxins onto the surface of virally infected cells.
E) are specialists in killing bacteria.

Question 38

Which of the following are among the activities of neutrophils?

A) enzyme production that leads to the formation of nitric oxide
B) formation of neutrophil extracellular traps
C) phagocytosis
D) formation of neutrophil extracellular traps and phagocytosis
E) formation of neutrophil extracellular traps, phagocytosis, and production of nitric oxide

Question 39

Which of the following are chemotactic factors for phagocytes?

A) interferons and chemokines
B) chemokines and peptide fragments from complement
C) peptide fragments from complement
D) interferons
E) chemokines

Question 40

Which of the following pairs is MISMATCHED?

A) microglial cells; spleen
B) alveolar macrophage; lungs
C) dendritic cells; epidermis
D) macrophages; lymph nodes
E) microglial cells; brain

Question 41

The process known as (complement/inflammation/phagocytosis) brings a variety of physical, chemical and cellular factors together to fight invading microorganisms.

Question 42

The (epithelial/goblet/mucous) cells in the tracheal mucous membrane produce mucus.

Question 43

The absence of necessary receptors is the basis of the defense against microbial invasion known as (natural/innate/species) resistance.

Question 44

Which of the following substances stimulates the phagocytic activity of phagocytes?

A) leukotrienes
B) antiviral proteins
C) beta interferons
D) alpha interferons
E) gamma interferons

Question 45

The normal microbiota compete with pathogens in a variety of ways to protect the body, creating a situation known as microbial (antagonism/competition/resistance).

Question 46

The oily substance that lowers the pH of the skin's surface to about pH 5 and is inhibitory to many bacteria is (sebum/sweat/serum).

Question 47

In the case of phagocytes, positive chemotaxis involves the use of (cilia/flagella/pseudopodia) to move toward the microorganism.

Question 48

Some pathogens produce toxins which function as (histamines/prostaglandins/pyrogens) to cause fever.

Question 49

The first and second lines of defense against microbial invasion are part of

A) adaptive immunity.
B) microbial antagonism.
C) species resistance.
D) innate immunity.
E) both species resistance and adaptive immunity.

Question 50

Intact skin layers are part of the body's (first/second/third) line of defense against pathogens.

Question 51

The components of the second line of defense against microbes may be characterized as

A) responders to invasion.
B) detecting the unique features of specific pathogens.
C) passive barriers.
D) mechanisms to strengthen the first line of defense.
E) both passive barriers and detecting specific pathogen features.

Question 52

The proportion of (plasma/leukocytes/RBCs), as determined by a differential white blood cell count, can serve as a sign of disease.

Question 53

Which of the following proteins are part of the first line of defense against microbial invasion?

A) interferons
B) defensins
C) C3 and C5
D) TLRs
E) NOD proteins

Question 54

The redness and heat of acute inflammation are caused in part by the production of (bradykinin/platelets/fibrinogen) during the formation of blood clots.

Question 55

Phagocytes kill a pathogen once it has been ingested, whereas eosinophils and (MAC/NK/NOD) lymphocytes can accomplish extracellular killing by secreting toxins. (Be sure to use capital letters in your answer.)

Question 56

In a process called (cytokinesis/hematopoiesis/hematocrit), blood stem cells located in the bone marrow produce the three types of formed elements found in the blood.

Question 57

Sweat glands produce (lysozyme/dermcidin/acid), which destroys the cell wall of bacteria by cleaving the bonds between the sugar subunits present in the wall.

Question 58

Neutrophils use their own (DNA/RNA/TLR) in the formation of NETs to trap bacteria.

Question 59

Which of the following cells can use nonphagocytic means to kill bacteria?

A) neutrophils
B) eosinophils
C) macrophages
D) natural killer cells
E) both eosinophils and neutrophils

Question 60

The first and second lines of defense respond to invading microbes by (specific/nonspecific) mechanisms.

Question 61

Interferons alpha and beta are effective against viruses.

Question 62

Sweat can cause damage to bacteria because it contains salt and lysozyme.

Question 63

What are macrophages, and what are their functions?

Question 64

What is phagocytosis? What does it involve?

Question 65

The resident microbiota have no role in defense against pathogen invasion.

Question 66

Describe the events of the acute inflammatory response and their effect on a site of infection. Include the cells and chemicals involved.

Question 67

Some toll- like receptors (TLRs) are found on the surface of host cells and recognize specific microbial molecules.

Question 68

Inflammation is an important part of the body's first line of defense, and it involves migration of phagocytes to the area.

Question 69

Describe at least three physical mechanisms that are part of the first line of defense.

Question 70

The growth of some microbes is inhibited by elevated body temperature.

Question 71

The various phagocytic cells of the second line of defense target specific microbes by their unique structures.

Question 72

Histamine and prostaglandins are involved in inflammatory reactions.

Question 73

The alternative pathway for complement activation is more effective than the classical pathway.

Question 74

Examine the WBC count and differential data in the table. What type of disease is indicated by this set of data?

Question 75

Neutrophils can kill bacteria by nonphagocytic mechanisms.