Deck 13: Innate Immunity

Question 1

Which forms of immunity provide only temporary protection against infection. (Select all that apply)

A) natural passive immunity
B) natural active immunity
C) artificial passive immunity
D) artificial active immunity

Answer 1

A,C

Question 2

__________ is protection against infection by the medical stimulation of immune cells to trigger their activation without pathogen exposure.

A) Natural passive immunity
B) Natural active immunity
C) Artificial passive immunity
D) Artificial active immunity

Answer 2

D

Question 3

Transplacental transfer of maternal antibodies provides ______________ to a developing fetus.

A) natural passive immunity
B) natural active immunity
C) artificial passive immunity
D) artificial active immunity

Answer 3

A

Question 4

___________ is lifelong immunity to infection by a pathogen following recovery from an initial exposure.

A) Natural passive immunity
B) Natural active immunity
C) Artificial passive immunity
D) Artificial active immunity

Question 5

Although designed to attack foreign invaders, immune system dysfunction can result in undesirable consequences such as ________. (Select all that apply)

A) transplant rejection
B) allergic reactions
C) autoimmune disorders like multiple sclerosis
D) artificial active immunity

Question 6

Normal, healthy host cells are identified as "self", rather than "non-self" such as a pathogen, by the immune system monitoring ____________ surface markers expressed on their plasma membrane. (Select all that apply)

A) phospholipids
B) proteins
C) glycoproteins
D) steroids

Question 7

First-line defenses of innate immunity include physical defenses such as _________. (Select all that apply)

A) fever
B) tears
C) mucous membranes
D) gastric secretions

Question 8

Second-line cellular defenses of innate immunity include action by the following cell types: _________. (Select all that apply)

A) B cells
B) T cells
C) neutrophils
D) natural killer cells

Question 9

Washing actions such as ___________, dislodge microorganisms trying to attach to the host. (Select all that apply)

A) sebaceous secretions
B) vaginal secretions
C) gastric secretions
D) urination

Question 10

Second-line chemical defenses of innate immunity use ________ to kill microorganisms by desiccation.

A) sebaceous secretions
B) vaginal secretions
C) gastric secretions
D) mucous

Question 11

Innate immunity is characterized by ____________.

A) rapid responses to pathogen invasion
B) enhanced responses with subsequent exposures to the pathogen
C) pathogen-specific elimination strategies
D) memory and specificity

Question 12

____________ are small molecules secreted by white blood cells and used to coordinate the activity of immune cells.

A) Lysozymes
B) Cytokines
C) Complement
D) Interferons

Question 13

When pathogens overcome innate responses, adaptive immunity provides a third-line of defense by _______.

A) responding rapidly to infection
B) launching a more vigorous attack with subsequent exposures
C) triggering very high fever
D) consistently sending natural killer cells to attack microorganisms

Question 14

The immune system contains components of the __________ system. (Select all that apply)

A) circulatory
B) respiratory
C) reticuloendothelial
D) endocrine

Question 15

Immune privileged sites such as the __________, have few if any associated lymphatic vessels. (Select all that apply)

A) placenta
B) testes
C) ovaries
D) brain

Question 16

The reticuloendothelial system (RES) _____________. (Select all that apply)

A) is also known as the MPS or mononuclear phagocyte system
B) contains a diverse collection of phagocytic cells
C) promotes immune surveillance as phagocytes patrol by following connective tissue fibers
D) processes phagocyte-ingested pathogens to facilitate their recognition by cells of the adaptive immune system

Question 17

Which phagocytic cell type is mismatched with its location?

A) Kupffer cells: liver
B) Langerhans cells: lungs
C) Monocytes: blood
D) Microglial cells: central nervous system

Question 18

____________________ is a primary lymphoid organ.

A) MALT
B) Thymus
C) Blood
D) Peyer's patches

Question 19

Identify this component of the immune system and its principle function.

A) spleen: filtering antigens from blood
B) thymus: activation of NK cells
C) bone marrow: maturation of B cells
D) lymph node: trap antigens circulating in lymph

Question 20

Plasma cells ____________________. (Select all that apply)

A) are mature T cells
B) are mature B cells
C) are powerful phagocytic cells
D) secrete antibodies

Question 21

GALT is ideally positioned to eliminate pathogens ____________.

A) that entered the host by consumption of contaminated food
B) circulating in the blood
C) inhaled during breathing
D) that enter by a skin abrasion

Question 22

MALT includes all of the following except ____________.

A) spleen
B) BALT
C) Peyer's patches
D) appendix

Question 23

Physical defense mechanisms against pathogens are characterized as ____________. (Select all that apply)

A) heat
B) lysozyme
C) washings
D) phagocytosis

Question 24

Which of the following features make skin a formidable barrier against pathogen invasion? (Select all that apply)

A) keratinized epidermal cells
B) tight junctions to prevent pathogen penetration between cells
C) the sweeping action of cilia to remove pathogens
D) continuous regeneration of epidermal cells allows sloughing off of surface cells and any associated pathogens

Question 25

Tightly connected endothelial cells lining the brain capillaries ________. (Select all that apply)

A) regulate the transport of material into the brain, restricting pathogen access
B) restrict oxygen transport making it impossible for brain infections by aerobic pathogens
C) send a signal to the hypothalamus to generate a fever to prevent pathogen growth
D) are known as the blood-brain barrier

Question 26

Which of the following is considered a washing action to remove pathogens and minimize infection risk? (Select all that apply)

A) urination to dislodge flagellated bacteria swimming up the urethra to the bladder
B) tearing to rinse micro-organisms out of the eyes
C) secretion of defensins by normal microbiota in the gut
D) vomiting and/or diarrhea to rapidly remove gastrointestinal pathogens

Question 27

In adults without underlying medical conditions, ideal pathogen-fighting temperature is a fever of 102-103^o F because _________. (Select all that apply)

A) interferon levels are reduced
B) host cells experience denaturation
C) white blood cell production is minimized
D) bacterial growth rates are inhibited

Question 28

This study correlating fever with growth of the bacteria causing pneumococcal meningitis in rabbits demonstrated that _____________________.

A) as body temperature increases so does the bacterial growth rate
B) there is an inverse relationship between body temperature and bacterial growth rate
C) harmful fever levels correlate with enhanced bacterial growth
D) there is a logarithmic decline in bacterial growth with every 2^o F increase in fever

Question 29

What bacterium can cause a gastric ulcer?

A) Escherichia coli
B) Salmonella typhi
C) Enterobacter aerogenes
D) Helicobacter pylori

Question 30

A gastric ulcer caused by a bacterial infection _____________ which yields a positive CLO test.

A) drops the pH
B) turns methyl red, a pH indicator, an orangish color
C) results in the production of CO₂ and ammonia
D) enhances the activity of the stomach's proton pumps

Question 31

Which of the following chemical defenses is NOT correctly matched to its mechanism of action?

A) lysozyme degrades mycolic acid in bacterial cell walls
B) the high salt concentration in mucus desiccates most pathogens
C) low pH and digestive enzymes destroy microbes not adapted to conditions of the gastrointestinal tract
D) gut microbiota secrete small antimicrobial proteins to kill pathogens

Question 32

According to the results of the Human Microbiome Project, _________ is the predominant component of the normal skin microbiota.

A) Pseudomonas
B) Janthinobacterium
C) Staphylococcus
D) Helicobacter

Question 33

Compare the gut microbiome composition of a normal healthy adult to the composition of an obese individual. Which component(s) is/are noticeably increased in the obese patient? (Select all that apply)

A) Firmicutes
B) Bacteroidetes
C) Actinobacteria
D) Proteobacteria

Question 34

The composition of our normal gut microbiota appears to play a significant role in biological defense against infection. Which of the following factors can influence the makeup of your gut microbial community, consequently impacting your health? (Select all that apply)

A) diet
B) age
C) medical treatments such as antibiotics or radiation therapy
D) level of body fat

Question 35

The immune system is developing during infancy, most effective during adulthood, and declining during old age. Examine the composition of the gut microbiome to determine a potential correlation with immune activity.

A) Proteobacteria are the dominant component of the microbiome during the time of greatest immune effectiveness
B) The immune system is least effective in infancy and elderly individuals when Actinobacteria levels are highest
C) The immune system is least effective in infancy and elderly individuals when Firmicutes levels are reduced compared to adulthood
D) The immune system is most effective when Bacteroides is the dominant component of the gut microbiome

Question 36

Which of the following immature blood cells is NOT correctly matched to its mature counterpart?

A) reticulocyte/erythrocyte
B) megakaryoblast/platelet
C) myeloblast/NK cell
D) monoblast/monocyte

Question 37

All circulating blood cells are produced by ___________which occurs in the _______.

A) hemolysis/spleen
B) hemocytosis/thymus
C) hematopoiesis/bone marrow
D) myelopoiesis/spleen

Question 38

Which of the following blood cells is not a granulocyte? (Select all that apply)

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

Question 39

Identify this white blood cell.

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

Question 40

The primary immune function of ___________ is ___________.

A) basophils/defense against helminths
B) eosinophils/production of antibodies
C) lymphocytes/destroying phagocytized pathogens using the respiratory burst
D) monocytes/development of tissue macrophages

Question 41

A blood smear prepared for a differential count _________. (Select all that apply)

A) is stained with crystal violet
B) is scanned to observe 100 leukocytes in the sample under the microscope
C) provides life-saving patient information regarding the number and condition of erythrocytes
D) assists physicians with patient diagnosis based on altered leukocyte proportions

Question 42

Pathogen-associated molecular patterns (PAMPs) _________. (Select all that apply)

A) are recognized by neutrophils, dendritic cells and NK cells
B) include lipoteichoic acid and lipid A
C) are highly conserved molecular arrangements common on the surfaces of many pathogens
D) are also known as pattern recognition receptors

Question 43

Pattern recognition receptors (PRRs) __________________. (Select all that apply)

A) recognize and bind to PAMPS
B) include complement, which is a soluble receptor able to bind PAMPs on circulating pathogens
C) are often present on host cell plasma membranes
D) such as NOD-like receptors, are located in the cytoplasm to bind PAMPs on intracellular pathogen

Question 44

Intracellular signaling by PAMP/PRR binding in NK cells _____________. (Select all that apply)

A) releases perforin that forms membrane pores
B) releases the protease granzyme
C) triggers apoptosis
D) triggers hematopoiesis

Question 45

White blood cells such as __________eliminate pathogens by phagocytosis. (Select all that apply)

A) neutrophils
B) macrophages
C) monocytes
D) eosinophils

Question 46

Common opsonins include ___________ and lead to ___________.

A) antibodies/inflammation
B) C3b/enhanced phagocytosis
C) C-reactive protein/reduced respiratory burst
D) mannose-binding lectins/granzyme production

Question 47

Once phagocytized, engulfed pathogens are destroyed by _________. (Select all that apply)

A) enzymatic degradation
B) alkylation
C) defensins
D) complement fixation

Question 48

Inflammation is characterized by all of the following signs and symptoms except _________________.

A) redness
B) stiffness
C) swelling
D) heat

Question 49

Inflammation may be triggered by _________________. (Select all that apply)

A) physical trauma
B) chemical damage
C) pathogen attack
D) allergen exposure

Question 50

The inflammatory process promotes _________________. (Select all that apply)

A) bringing phagocytic cells to the site of injury or infection
B) walling off invading pathogens to prevent their spread to other tissues
C) dilution of pathogen-secreted toxins
D) repair of tissue damage to facilitate resumption of normal function

Question 51

Which inflammatory molecular mediator is incorrectly matched to its function?

A) histamine/fever elevation
B) leukotrienes/increased capillary permeability
C) IL-1/increased expression of endothelial adhesion molecules
D) IL-1/leukocyte chemotaxis

Question 52

The correct sequence of steps involved in the inflammatory response is ________.
1) diapedesis of leukocytes out of capillaries and into surrounding tissues
2) enhanced blood flow to injured area with subsequent development of heat and redness
3) release of inflammatory mediators from a variety of sources triggering vasodilation
4) plasma leaves blood vessels brining various agents of help to damaged tissue
5) macrophages and lymphocytes get rid of pus and cellular debris, and homeostasis is reestablished
6) increased fluid in tissues leads to edema, pain and phagocytosis of invading pathogens

A) 3, 2, 1, 4, 6, 5
B) 1, 2, 3, 4, 5
C) 1, 3, 5, 6, 4, 2
D) 2, 3, 1, 4, 6, 5

Question 53

The complement system _____________. (Select all that apply)

A) is a series of 30+ serum and surface proteins
B) ultimately creates a transmembrane tube that causes the osmotic rupture of the pathogen
C) is composed of 5 different cascades to maximize pathogen elimination
D) responds stronger with subsequent pathogen exposures

Question 54

Which of the complement pathways represent an innate immune response? (Select all that apply)

A) alternative
B) classical
C) lectin
D) mannan

Question 55

Indicate the correct order of events in the alternative complement pathway.
1-C5b binds with C6, C7 and C8 forming a complex on the pathogen membrane
2-Properdin binds C3b and Bb to form C3 convertase
3-Factor D cleaves Factor B allowing Bb to bind C3b on pathogen surface
4-Pore formed by MAC triggers osmotic cell lysis
5-C3 convertase activity generates C5 convertase

A) 3, 2, 1, 4, 6, 5
B) 1, 2, 3, 4, 5
C) 1, 3, 5, 6, 4, 2
D) 2, 3, 1, 4, 6, 5

Question 56

Interferons (IFNs) ________________. (Select all that apply)

A) are a large family of glycoprotein cytokines
B) are named for their ability to interfere with viral replication cycles
C) are capable of inducing an antiviral state by altering the host cell's gene expression
D) trigger the production of antiviral proteins to defend an infected host cell

Question 57

Antiviral proteins defend an infected host cell by ________________. (Select all that apply)

A) promoting viral gene expression
B) degrading viral RNA
C) impeding viral self-assembly
D) enhancing viral protein synthesis

Question 58

Because of their ability to control viral infections and suppress the growth of malignant cells, interferons have been therapeutically administered. Indicate the reason(s) for the limited use of these immune proteins that appears to be a highly effective treatment. (Select all that apply)

A) Interferon use may cause Kaposi's sarcoma
B) Interferon use carries a dangerously high level of allergic reaction
C) Interferons are unstable, so they are only effective at treating short-term viral infections
D) Interferon side effects can be deadly and include cardiac toxicity and bond marrow suppression

Question 59

The correct sequence of events in the action of interferon is ________________.
1) viral infection of host cells causing rapid production and secretion of Type I IFNs
2) host cell produces antiviral proteins that can degrade viral RNA, inhibit protein synthesis and virion assembly and prevent viral gene expression
3) modification of neighboring cell's gene expression induces an antiviral state
4) binding of IFNs to receptors on uninfected neighboring cells

A) 1, 2, 3, 4
B) 1, 4, 3, 2
C) 2, 1, 4, 3
D) 3, 1, 4, 2

Question 60

IFNs produced using recombinant DNA technology are being used with less side effects in patients infected with all of the following except ________________.

A) Hepatitis A
B) HIV
C) Genital herpes
D) Hepatitis B

Question 61

___________________ is an iron-scavenging protein secreted by bacterial pathogens to promote their growth by extracting the nutrient from host iron-storage proteins.

A) Ferritin
B) Lactoferrin
C) Siderophore
D) Transferrin

Question 62

Which of the following cytokines is incorrectly paired with its function?

A) Histamine/vasoactive molecule; increases vascular permeability
B) Interleukin-2/proliferation and activation of B cells, T cells and NK cells
C) Leukotrienes/promotes inflammation and elevates fever
D) Transforming growth factors/inhibition of B cells, T cells, and macrophages

Question 63

Which of the following is NOT a small antimicrobial peptide?

A) defensins
B) protegrins
C) siderophores
D) prostaglandins