Deck 15: Innate Immunity

Question 1

Receptors known as NOD proteins detect molecules associated with microbes

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

Answer 1

A

Question 2

The surface of the skin serves as a barrier to microbial invasion in part because it is

A) constantly patrolled by neutrophils.
B) an acidic, high-salt environment.
C) a high-salt environment.
D) acidic.
E) moisturized by mucus secretions.

Answer 2

B

Question 3

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.

Answer 3

E

Question 4

What is the function of NK cells?

A) They phagocytose virus particles.
B) They release defensins to damage bacteria.
C) They identify and poison virus-infected cells.
D) They release toxins to damage helminth parasites.
E) They release interferons in response to detecting virus particles.

Question 5

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

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

Question 6

A monocyte leaves a capillary in the lungs and enters the lung tissue. It then matures to become a(n)

A) microglial cell.
B) dendritic cell.
C) goblet cell.
D) alveolar macrophage.
E) mast cell.

Question 7

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

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

Question 8

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

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

Question 9

Mucus and sweat contain which damage and kill bacteria.

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

Question 10

Response to specific pathogens that can improve with subsequent exposure is

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

Question 11

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

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

Question 12

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

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

Question 13

Which of the following is the BEST definition of ʺmicrobial antagonismʺ?

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 presence of normal microbiota that can become pathogens under certain conditions
D) the presence of pathogens on the surface of the skin, which will invade the body through abrasions
E) the ability of microbiota to mutate into pathogens

Question 14

What do the nasal cavity, mouth, and urinary system have in common?

A) The outer layers remain intact for many days.
B) They are lined with mucous membranes.
C) They are lined with tightly packed dead cells.
D) They have roles in excretion of waste products.
E) They are poorly vascularized.

Question 15

The complement cascade and its by-products contribute to

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

Question 16

Which of the following are chemotactic factors for phagocytes?

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

Question 17

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

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

Question 18

Phagocytic cells in the epidermis known as contribute to its ability to prevent microbial invasion.

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

Question 19

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

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

Question 20

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

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

Question 21

Which of the following leukocyte functions do macrophages carry out?

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

Question 22

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

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

Question 23

The phenomenon of facilitates the binding of phagocyte pseudopodia to pathogens.

A) MAC formation
B) opsonization
C) chemotaxis
D) margination
E) diapedesis

Question 24

In addition to phagocytosis, neutrophils can kill bacteria by producing

A) hypochlorite.
B) histamines.
C) interferons.
D) nitric oxide.
E) both hypochlorite and nitric oxide.

Question 25

Which of the following statements is TRUE of eosinophils?

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

Question 26

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

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

Question 27

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

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

Question 28

What type of white blood cell is shown in Figure 15 -1?

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

Question 29

Wandering macrophages recognize microorganisms by means of

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

Question 30

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

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

Question 31

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

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

Question 32

Neutrophils produce , which can be triggered by sugar molecules on the surface of microbes to damage the microbes.

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

Question 33

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

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

Question 34

Fever is beneficial during viral infection because the higher temperature

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

Question 35

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

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

Question 36

Phagocytes are brought to a site of infection by

A) bradykinin gradients.
B) detection of NOD proteins.
C) fluid flow out of capillaries.
D) detection of chemokines and complement factor gradients.
E) gradients of interferons.

Question 37

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

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

Question 38

What feature of the skin creates a physical barrier to microbial invasion?

A) The fine hairs move microbes to mucous membranes for phagocytosis.
B) The outer layers are composed of cells full of protein which forms NETs to trap microbes until they are shed.
C) The oil secreted onto the surface of the skin traps microbes, preventing penetration.
D) The surface is constantly patrolled by phagocytic cells.
E) The outer layers are dead cells, tightly linked together, and are frequently shed.

Question 39

Healthy cells produce in response to interferons.

A) antiviral proteins
B) antimicrobial peptides
C) MACs
D) NOD
E) TLRs

Question 40

The process shown in the figure will lead to

A) vasodilation.
B) formation of MACs.
C) chemotaxis and opsonization.
D) capillary constriction.
E) formation of NETS.

Question 41

Lectins specific for mannose can lead to attack on fungi by

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

Question 42

Neutrophils can kill bacteria by nonphagocytic mechanisms.

Question 43

The third line of defense against infecting microbes is called (adaptive/innate/natural) immunity.

Question 44

First line of defense may be described as

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

Question 45

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

Question 46

Cells of the second line of defense that poison virus-infected cells are lymphocytes known as NK (natural killer) cells.

Question 47

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

Question 48

Histamine and prostaglandins are involved in inflammatory reactions.

Question 49

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

Question 50

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

Question 51

The leukocytes called natural killer lymphocytes

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

Question 52

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

Question 53

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

Question 54

Phagocytes can directly detect microbial molecules like LPS and peptidoglycan by means of

A) the complement cascade.
B) toll-like receptors.
C) bradykinin binding.
D) interferon receptors.
E) PAMPs.

Question 55

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 56

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

Question 57

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

Question 58

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

Question 59

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

Question 60

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

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

Question 61

Neutrophils primarily kill (bacterial/helminth/fungus/viral) pathogens.

Question 62

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

Question 63

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

Question 64

Some toll-like receptors (TLRs) are found in phagosome membranes and bind forms of nucleic acids. Discuss how these TLRs and their location can play a role in the response to viral infection. (You may have to recall information from one or more previous chapters.)

Question 65

What is phagocytosis? What does it involve?

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

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 68

The TLRs of phagocytic cells bind (MAC/NOD/PAMP) molecules. (Be sure to use capital letters in your answer.)

Question 69

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

Question 70

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

Question 71

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 72

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

Question 73

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 74

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

Question 75

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