Microbiology Chapter 14: Innate Immune Response

Label the following diagram showing the body's borders to better familiarize yourself with the first line defenses.

**start at 12 o'clock going clockwise: Mouth Eye Skin Anus Urogenital tract Digestive tract Respiratory tract middle: Mucous membranes

Complete the following diagram of the different activation pathways of the complement system.

*left to right* Top: C3b binding, Mannose-binding lectin, Antibodies Middle: Inflammatory response, Formation of C3 convertase, Opsonization Bottom: Lysis of foreign cells

Match the examples of antimicrobial substances with the corresponding areas in the human body where they function.

*top to bottom* Left side: Lysozyme, removal of inhaled particles, physical barrier of skin, rapid pH change, pH and normal microbiota Right side: Mucus and cilia, low pH of the stomach, flushing of the urinary tract

Match the following cytokines with their general functions. 1. These cytokines are important in the chemotaxis of immune cells. 2. These cytokines are important in the multiplication and differentiation of leukocytes. 3. These cytokines are important in the control of virally-infected cells. 4. These cytokines are produced by leukocytes and are important in both innate and adaptive immunity. 5. These cytokines are important as triggers for inflammation and apoptosis.

1. Chemokines 2. Colony-stimulating factors 3. Interferons 4. Interleukins 5. Tumor necrosis factor

Please match the cell to the statement that most accurately describes its main function to test your understanding of blood cells that function in nonspecific immunity. 1. Main phagocytes in circulation 2. Like eosinophils, they are involved in inflammation and allergic reactions 3. Phagocytic cells that leave circulation and differentiate into macrophages 4. Display no antigen specificity but are active against tumor and virally infected cells

1. Neutrophils 2. Basophils 3. Monocytes 4. Natural killer cells

Toll-like receptors (TLRs) bind molecules on pathogens. This is helpful to the immune response because TLRs: A. are capable of directly lysing (destroying) the microbes, helping our immune responses by eliminating pathogens. B. are delivery mechanisms for the immune responses - they capture pathogens and then direct them to receptors on the immune system cells that are best capable of eliminating them. C. recognize broad categories of molecules that should not be in our system, as we don't have these molecules on our own cells. D. recognize small and highly unique areas on an individual pathogenic microbe, providing the most specific and selective response possible.

C. recognize broad categories of molecules that should not be in our system, as we don't have these molecules on our own cells.

Normal microbiota: A. are the organisms that typically reside on and in your body. B. protect against infection by pathogens. C. enhance infection by pathogens. D. play no role in affecting pathogen growth. E. are the organisms that typically reside on and in your body AND protect against infection by pathogens.

E. are the organisms that typically reside on and in your body AND protect against infection by pathogens.

Label the following diagrams of stratified and columnar epithellum to better understand the body's epithelial barriers.

Stratified epithelium: 1. nucleus 2. basement membrane 3. connective tissue Columnar epithelium: 1. Cilia 2. Mucus producing cell 3. Columnar cell

Inactivation of a cell's interferon genes would likely have which outcome? a. The cell would no longer alert neighboring cells to the presence of double-stranded RNA. b. The cells surrounding the defective cell would not lyse when infected with a virus. c. The cells surrounding the defective cell would no longer respond to a bacterial infection. d. The cells surrounding the defective cell would undergo apoptosis.

a. The cell would no longer alert neighboring cells to the presence of double-stranded RNA.

If a cell did not express any of the pattern recognition receptors (PRRs), to which of the following would it still respond? a. Peptidoglycan b. Cytokines c. Flagellin d. LPS e. Nucleic acids

b. Cytokines

A lack of which component would have the greatest impact on a person's health? a. Complement proteins. b. Hematopoietic stem cells. c. Natural killer cells. d. Lysozyme. e. Transferrin.

b. Hematopoietic stem cells.

Which of the following statements about interferon is TRUE? a. It causes the virally infected cell to produce antiviral proteins. b. It is produced in response to double-stranded RNA. c. It is produced in response to double-stranded DNA. d. It causes virally infected cells to lyse. e. It causes surrounding cells to undergo apoptosis.

b. It is produced in response to double-stranded RNA.

Which of the following are considered physical (versus chemical) factors that contribute to the skin and mucous membranes protective role against infection? a. Lysozyme b. Layers of cells c. Mucociliary escalator d. Antimicrobial peptides e. Flushing of urinary tract

b. Layers of cells c. Mucociliary escalator e. Flushing of urinary tract

Skin and mucous membranes are mostly involved in: a. adaptive immunity. b. innate immunity. c. autoimmunity. d. irregular immunity.

b. innate immunity.

Which of the following is LEAST likely to be recognized by a toll-like receptor anchored in the cytoplasmic membrane? a. flagellin b. nucleic acid c. peptidoglycan d. pilin e. lipopolysaccharide

b. nucleic acid

Which of the following is a function of the mucociliary escalator? a. removes microbes from all body cavities b. removes microbes form the respiratory tract c. kills and digest microorganisms remove microbes form the urinary tract d. induce bacterial apoptosis

b. removes microbes form the respiratory tract

People who have compromised first-line defenses are susceptible to opportunistic pathogens. Which situation would be an example of a compromised first-line defense? a. A person with an abnormally low number of neutrophils. b. A baby that is unable to breast feed. c. A burn patient who has lost extensive areas of the skin. d. A person with a latent viral infection.

c. A burn patient who has lost extensive areas of the skin.

The cells primarily involved in all immune responses are the: a. erythrocytes. b. platelets. c. leukocytes. d. osteocytes.

c. leukocytes.

Interferons, complement, lysozyme, and lactoferrin are all examples of: a. specific antimicrobial factors. b. immune enzymes. c. nonspecific antimicrobial factors. d. cytokines.

c. nonspecific antimicrobial factors.

A pathogen that can avoid binding by complement C3b would directly protect itself from: a. inducing lysis. b. inducing aopotosis. c. opsonization. d. triggering inflammation. e. antibodies.

c. opsonization.