Micro Exam 2 Ultimate Quizlet

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Mechanisms of type II hypersensitivity

1. Opsonization and phagocytosis. 2. Complement &Fc receptor mediated inflammation 3. Antibody mediated cellular dysfunction

C. Capsule

Choose the best answer related to the statement Role in adhesion and colonization A. Endospores B. Pili C. Capsule D. Flagella

B. Pili

Choose the best answer related to the statement Role in transfer of genetic material A. Endospores B. Pili C. Capsule D. Flagella

B. Recruitment of neutrophils

Helicobacter pylori is a human gastrointestinal pathogen that can lead to a state of chronic GI inflammation in some individuals, and has been linked to gastric ulcers and other diseases. Studies have shown that human muscosal gastric biopsies of infected individuals have dendritic cells producing IL-23 in response to stimulation with live H. Pylori. Given these findings, which of the following responses would be enhanced in the GI tract of H pylori infected individuals compared to uninfected individuals? A. Mucus production by goblet cells B. Recruitment of neutrophils C. Recruitment of eosinophils D. Production of IL-13

False

Human cells are capable of using the TCA cycle under anaerobic conditions True/False

False Remember type VI reactions take time and divalent molecules can bind to MHC I molecules

Hypersensitivity responses to divalent cations such as nickel are relatively common. I diluviales sensitized to these metals will develop a skin rash within 15 minutes of putting on a bracelet or ring containing that metal. True/False

A. CD4 single positive T cells

Identify the cell type circled in the image A. CD4 single positive T cells B. CD8 single positive T cells C. CD4 negative T cells D. CD4CD8 double positive T cells

E

Identify the letter that indicates DNA ligase

D

Identify the letter that indicates DNA polymerase I

C

Identify the letter that indicates DNA polymerase III

B

Identify the letter that indicates Helicase

B

Identify the letter that indicates Okazaki fragments

A

Identify the letter that indicates Single Stranded Binding Protein (SSBP)

A

Identify the letter that indicates Topoisomerase

C

Identify the letter that indicates the Lagging strand

D

Identify the letter that indicates the Leading strand

B. Specialized transduction

Identify the types of transduction related to the statement below A prophage integrates into a specific site (att) on the bacterial chromosome A. Generalized transduction B. Specialized transduction

A. Generalized transduction

Identify the types of transduction related to the statement below Any bacterial gene stands equal probability of being transduced A. Generalized transduction B. Specialized transduction

B. Specialized transduction

Identify the types of transduction related to the statement below Which one is associated with lysogenic phages A. Generalized transduction B. Specialized transduction

E. Aerobic respiration

Identify which bacterial metabolism pathway the following statement correlates to: Complete oxidation of glucose that leads to generation of 38 ATP in bacteria but only 30 in eukaryotes A. Entner-Doudoroff pathway B. Fermentation C. Glycolysis D. Proton motive force E. Aerobic respiration

F. Glyoxylate cycle

Identify which bacterial metabolism pathway the following statement correlates to: Anaplerotic cycle that replenishes key TCA intermediates A. Glycolytic or Embden-Meyerhof pathway B. Krebs cycle (TCA cycle) C. Electron transport/oxidative phosphorylation D. Pentose phosphate shunt E. Entner-Doudoroff pathway F. Glyoxylate cycle

CD8+ T cells

Immune responses to tumors have been studied extensively in mice, using transplantable tumors injected into syngeneic mice. The basis for many of these studies is the assumption that the process of tumorigenesis generates mutations in genes encoding self-antigens that would allow the immune system to see these mutant proteins as 'foreign'. In the scenario, the dominant immune response targeting the tumor cells would be mediated by:

C. CD8+ T cells

Immune responses to tumors have been studied extensively in mice, using transplantable tumors injected into syngeneic mice. The basis for many of these studies is the assumption that the process of tumorigenesis generates mutations in genes encoding self-antigens that would allow the immune system to see these mutant proteins as 'foreign'. In the scenario, the dominant immune response targeting the tumor cells would be mediated by: A. Antibodies B. CD4+ TH1 cells C. CD8+ T cells D. NK cells E. FcR+ phagocytic cells

DNA; Chromatin proteins; Ribonucleoprotein antigens [All of the above]

In systemic lupus erythematosus the autoantigen targeted by the immune system is not tissue-specific wherein the autoantibodies and autoreactive T cells are made against: A. DNA B. Chromatin proteins C. Ribonucleoprotein antigens D. All of the above

D. All of the above Remember its systemic b/c DNA is not tissue specific and can be expressed in the body and remember Ribonucleoprotein antigens are also called smith antigens

In systemic lupus erythematosus, the autoantigen targeted by the immune system is not tissue-specific wherein the autoantibodies and auto reactive T cells are made against: A. DNA B. Chromatin proteins C. Ribonucleoprotein antigens D. All of the above

A. Purple

In the Gram Stain sequence, which color do the Gram negative cells become before decolorization with alcohol? A. Purple B. Red C. Brown (color of iodine) D. Clear

A. Purple

In the Gram Stain sequence, which color do the Gram positive cells become at the end of decolorization? A. Purple B. Red C. Fluorescent pink D. Clear

A.

Most effector T cells migrate out of secondary lymphoid organs and into tissues to exert their function. In which of the cases shown in the figure will the TH1 effector cell undergo long-lived interactions with its target cell, an infected macrophage? Assume all of the target cells shown below are infected with the pathogen recognized by the specific TH1 cells.

A.

Once an individual becomes sensitized to an allergen, such as an inhaled antigen, the allergic response can become self-amplifying upon each re-exposure to the allergen. Thus, even in the absence of CD4 T2 cell activation, increases in IgE secretion by mucosal-resident plasma cells can be induced by: A. IL-4 secretion and CD40-ligand expression by mast cells and basophils B. Inflammatory macrophages recruited to the site of allergen stimulation C. Eosinophils that are stimulated by the production of IL-4 in the mucosal tissue D. Dendritic cells that have received TLR stimulation E. The activation of the complement cascade following allergen encounter

A. IL-4 secretion and CD40-ligand expression by mast cells and basophils

Once an individual becomes sensitized to an allergen, such as an inhaled antigen, the allergic response can become self-amplifying upon each re-exposure to the allergen. Thus, even in the absence of CD4 TH2 cell activation, increases in IgE secretion by mucosal-resident plasma cells can be induced by A. IL-4 secretion and CD40-ligand expression by mast cells and basophils B. Inflammatory macrophages recruited to the site of allergen stimulation C. Eosinophils that are stimulated by the production of IL-4 in the muscosal tissue D. Dendritic cells that have received TLR stimulation E. The activation of the complement cascade following allergen encounter

A. Bacterial

One mRNA encodes many proteins A. Bacterial B. Eukaryotic C. Both

B.

Only T-2 cells can initiate the chain of signals needed to induce B cells to class-switch to IgE. A. True B. False

False Can induced class switching from IgM to IgG?

Only TH2 cells can initiate the chain of signals needed to induce B cells to class-switch to IgE. True/False

B. Phagocytosis by FCgamma-receptor expressing macrophages in the spleen

RBCs are common targets of drug induced anemia, a disorder that occurs when some drugs bind to the surface of RBCs and trigger the development of IgG antibodies. Since the drug binding to the RBCs surface does not actually harm the RBCs the anemia resulting in this disorder is caused by: A. Trapping of RBCs on large endothelial vessels B. Phagocytosis by FCgamma-receptor expressing macrophages in the spleen C. Stimulation of CD4 T cells recognizing modified RBC surface proteins formed by the binding of the drug D. Stimulation of CD8 cytotoxic T cells that recognize drug-self protein conjugates and are triggered to kill the RBCs

C. Detects IgE antibodies against a specific allergen in the patients serum

Radioallergoabsorbent Test (RAST) A. Uses complement proteins B. Uses IgG antibody against a specific allergen C. Detects IgE antibodies against a specific allergen in the patients serum D. Uses enzymes for detecting the bound allergen

B. Non-homologous, site-specific, specialized

Select the correct type of recombination as it relates to the statement below Used by Ab genes, phages, and transposons A. Homologous or generalized B. Non-homologous, site-specific, specialized C. Both

C.

Simpson went through a lung transplant after five months of waiting for the suitable organ. During the pretransplant evaluation it was determined that he did not have cystic fibrosis or prior mold colonization. Infections during the first 30 days post transplantation could be related to surgery itself or nosocomial infections. Which one of the following would be the most likely source of infection in this patient within the first 30 days post transplant? A) Cryptococcus B) Pneumocystis C) Clostridioides difficile D) Aspergillosis

A. Teichoic acids

Structure that induces competence, resistance to lysis and binds to CD14/TLR2 of macrophages is ________________________ A. Teichoic acids B. Lipopolysaccharide C. Lipid A D. Periplasmic space E. Porins

B.

Type III hypersensitivity reactions are induced by A. Ig E antibodies B. Antigen - antibody [Ig G] complexes C. T cells D. IgG/IgM antibodies against cell surface antigens

A. Teichoic acid-rich outer membrane

Which of the following doe snot exist in nature? A. Teichoic acid-rich outer membrane B. Waxes in the cell wall C. A polypeptide capsule D. Wall-less bacteria E. Bacteria resistant to boiling temperatures

D.

Which of the following statements is FALSE A. Memory B cells constitutively secrete immunoglobulins B. Long lived plasma cells could be found in the spleen C. Memory B cells usually have high affinity for antigen D. Generation of long lived B cell memory requires CD4+ T cell help

E. All

Which one of these can generate mutations and DNA rearrangements A. Plasmids B. Phases C. Transposons D. A and B E. All

In the gram stain sequence, which color do the Gram positive cells become at the end of decolorization? a. Purple b. Red c. Fluorescent pink d. Clear

a. Purple

A 30-year-old female complains of fatigue, arthritis, rash, and changes in urine color. Laboratory testing reveals anemia, lymphopenia, and kidney inflammation. Assuming a diagnosis of SLE, which of the following is also likely to be present? a. Anti-LE antibodies b. Antinuclear antibodies c. Antiherpes antibodies d. Anti-CMV antibodies

b. Antinuclear antibodies

OmpC and OmpF are expressed differentially dpedning on osmolarity. In the presence of high osmolarity ompF translation is repressed by a. Phase variation b. Antisense RNA c. Competitive binding of repressor protein d. Attenuation

b. Antisense RNA

Which of the following is a characteristic of the human immunodeficiency virus (HIV), which causes AIDS? a. HIV only infects B cells. b. HIV is a retrovirus. c. Infection does not require a host cell receptor. d. After infection, cell death is immediate.

b. HIV is a retrovirus.

In the absence of lactose, the LacI repressor protein binds to the operator and ____ transcription. a. Induces b. Prevents

b. Prevents

During a co-culture experiment of two bacterial species, one that produces capsules and the other that does not, the lab tech observed that when bacterial samples were grown in agar, the bacteria that produced "rough" colonies now produced "smooth" ones. This effect was not seen if co-culture was done with two species grown separated by a <10 micron mesh. What process of DNA exchange is probably the one at play in this scenario? a. Transformation b. Transduction c. Conjugation d. Lysis e. Transfection

c. Conjugation

Physical effect of mast cell degranulation in eyes, nasal passages, and airways leads to: a. Increased peristalsis and fluid secretion b. Increased permeability and blood flow c. Vasoconstriction d. Decreased diameter, increased mucus secretion e. All of the above

d. Decreased diameter, increased mucus secretion

A patient has chicken pox. How does the varicella replicate? a. With the host cell DNA b. Using host cell DNA polymerase c. Using reverse transcriptase d. In the cytoplasm

d. In the cytoplasm

Recurrent pyogenic infections, eczema, and low platelets characterize this syndrome. The symptoms typically appear during the first year of life. It is an X-linked disease caused by mutations in the WASp gene, leading in actin filament assembly that is important for T cells to respond to an antigen presentation and for B cells to be activated by signal from BCR. These patients are therefore unable to mount an IgM response to the capsular polysaccharides of bacteria, such as pneumococci, whereas IgA and IgE levels can be elevated. a. Selective IgA immunodeficiency b. X-linked hyper-gamma-globulinemia c. DiGeorge's syndrome d. Wiskott-Alrich syndrome

d. Wiskott-Alrich syndrome

Phases of Systemic Immune Complex Disease

(1) Formation of antigen-antibody complexes in the circulation (2) Deposition of the immune complexes in various tissues (3) Initiation of an inflammatory reaction in various sites throughout the body

The activated T cells produce cytokines that lead to

(1) activate macrophages in the joint space, releasing degradative enzymes and other factors that perpetuate inflammation (2) activate B cells, resulting in the production of antibodies , some of which are directed against self-antigens in the joint • *80% of patients* with RA have serum IgM autoantibodies that bind to the Fc portions of the self IgG. These autoantibodies are called *rheumatoid factor(RF)* • They may form immune complexes with self-lgG that deposit in joints and other tissues, leading to inflammation and tissue damage. • The role of RF in the pathogenesis of the joint or extra articular lesions has not been established, and about 20% of patients do not have RF, suggesting that these autoantibodies are not essential for tissue injury in RA.

Causes of late-phase reaction

- *TNF and chemokine* which recruit and activate leukocytes - *IL-13* which stimulates epithelial cell mucus secretion

Examples of hypersensitivity type I

- Allergic asthma - Allergic conjunctivitis - Allergic rhinitis ("hay fever") - Anaphylaxis - Angioedema - Urticaria (hives) - Eosinophilia - Penicillin allergy - Cephalosporin allergy - Food allergy

Systemic reaction ( hypersensitivity I)

- Parenteral administration of antigens (e.g., in bee venom) or drugs (e.g., penicillin) result in systemic anaphylaxis. *Within minutes of exposure in a sensitized host * *followed in short order by* - dyspnea caused by bronchoconstriction &mucus hyper-secretion - Laryngeal edema with upper airway obstruction - The musculature of the entire GIT affected, with resultant vomiting, abdominal cramps, and diarrhea. *Without immediate intervention* - there may be systemic vasodilation with fall in blood pressure (anaphylactic shock) and the patient may progress to *circulatory collapse* and death within minutes.

Note

- Susceptibility to localized type I reactions is genetically controlled, and the term *atopy* is used to imply familial predisposition to such localized reactions. - Patients who suffer from nasobronchial allergy (including hay fever and some forms of asthma) have a family history of similar conditions

Rheumatoid Arthritis

- Systemic, chronic inflammatory disease affecting many tissues principally attacking the joints in the form of non suppurative proliferative synovitis - It progresses to destroy articular cartilage and underlying bone with resultant disabling arthritis - extra-articular involvement develops-for example, of the skin, heart, blood vessels, muscles, and lungs

Etiology and Pathogenesis of systemic lupus erythematosus (SLE)

- The defect in SLE is a *failure to maintain self-tolerance* - Autoantibodies ➡ antinuclear antibodies (ANAs). cause tissue damage either *directly* or in the form of immune complex deposits 1. Antinuclear Antibodies 2. Genetic predisposition to SLE 3. Non-genetic causes • UV radiation causes apoptosis of host cells, leading to an increased nuclear fragments ➡ develop ANAs • Drugs like procainamide and hydralazine > 6 months ➡ develop,ANAs • sex hormones ?? The mechanism of this hormonal effect is not known; Female > male)

granulomatous inflammation (formation of a granuloma)

- The initial perivascular CD4+ T-cell infiltrate is progressively replaced by macrophages over a period of 2 to 3 weeks - Activated macrophages become large, flat, and eosinophilic (epithelioid cells). - epithelioid cells fuse under the influence of cytokines (e.g., IFN-y) to form muitinudeated giant cells - microscopic aggregate of epithelioid cells, surrounded by collar of lymphocytes, with multi- nucleated giant cells, is called granuloma

Mechanism of Type IV Hypersensitivity (Delayed- Type Hypersensitivity)

- The reaction takes 2-3 days to develop (delayed) - cell mediated response - Macrophages as APC (antigen presenting cell) present antigen on its surface in association with *class II MHC* - This antigen is recognized by *CD4+Th1cells* - Macrophages secrete *IL12* - *IL-12* stimulates the proliferation of *effector* and memory CD4+ cells of the TH1 type - Prolonged DTH reactions against persistent antigene leads to granulomatous inflammation (formation of a granuloma)

Examples of type II hypersensitivity occur by opsonization

1. Autoimmune hemolytic anemia - The target Ag is Erythrocyte membrane proteins (Rh blood group antigens, I antigen) Phagocytosis ofRBC in spleen => Hemolysis, anemia with splenomegaly 2. Autoimmune thrombocytopenic purpura - The target Ag is Platelet membrane proteins - Phagocytosis of platelets in spleen ➡ Bleeding tendency with splenomegaly

B.

36-year-old male presents to his primary care physician for an annual exam. His history is significant for a successful kidney transplant 3 years ago. Physical exam findings are all within normal limits, but laboratory results demonstrate increased BUN and creatinine levels, which is Indicative of kidney damage. Which of the following is most likely being recognized to inititiate this response? A. Donor carbohydrates on endothelial cells acute. B. Donor alloantigen peptides in the context of recipient MHC C. Donor alloantigen peptides in the context of donor MHC D. Recipient peptides in the context of recipient MHC E. Recipient peptides in the context of donor MHC

A.

48-year-old male undergoes a kidney transplant. Within hours, he spikes a fever, has pain on the side of the transplant, and has decreased urine output. Lab values are significant for elevated BUN and creatinine levels, consistent with organ rejection. The type of rejection that is occurring is due to MSMS Faculty STL Instructor 3 shruti rai shruti rai A. preformed antibodies against carbohydrate antigens expressed on donor tissue. B. recipient CD8+ T cells specific for MHC class I on the transplanted donor tissue. C. recipient CD4+ T cells specific for MHC class II on the transplanted donor tissue. D. recipient NK cells that recognize the absence of MHC molecules on the transplanted donor tissue.

B. The casual organism lacks a cell wall

A 22 year old presents to the clinic with a persistent cough, high fever, inflammatory infiltrate on chest X-ray and exposure to a roommate with "walking pneumonia" symptoms who was treated successfully with macrolide antibiotics. A sputum Gram stain shows white blood cells but no organisms. What is the most likely explanation for no organisms seen in the gram stain? A. It is probably a viral infection B. The casual organism lacks a cell wall C. The presence of a polypeptide capsule blocks Gram staining

C. High levels of antibodies to double stranded DNA

A 22 year old woman has an erythematous rash on her face that gets worse when she goes out in the sun. She has lost about 10 lbs, complains about generalized joint pain and feels tired much of the time. Physical examination is normal except for the rash. Laboratory test reveal a WBC count of 5500 (Normal). Urine analysis shows elevated levels of protein in the urine but no RBCs, WBCs or bacteria. Which one of the following is the most likely laboratory finding in this disease? A. Decreased number of helper T cells B. Low level of C1 inhibitor C. High levels of antibodies to double stranded DNA D. Low microbicidal activity of neutrophils

high levels of antibodies to double stranded DNA

A 22 years old woman has an erythematous rash on her face that gets worse when she goes out in the sun. She has lost about 10 pounds, complains about generalized joint pain, and feels tired much of the time. Physical examination is normal except for the rash. Laboratory tests reveal a WBC count of 5500 [normal]. Urine analysis shows elevated levels of protein in the urine but no RBCs, WBCs or bacteria. Which one of the following is the most likely laboratory finding in this disease?

B. Molecular mimicry of a streptococcal antigen and cardiac myosin

A 30 year old woman with a previous history of rheumatic fever has recently developed a heart murmur. The most likely cause is A. Circulating rheumatoid factor B. Molecular mimicry of a streptococcal antigen and cardiac myosin C. A common variable immune deficiency D. A congenital abnormality

molecular mimicry of a streptococcal antigen and cardiac myosin

A 30 year old woman with a previous history of rheumatic fever has recently developed a heart murmur. The most likely cause is:

molecular mimicry of a streptococcal antigen and cardiac myosin

A 30 year old woman with a previous history of rheumatic fever has recently developed a heart murmur. The most likely cause is: A. circulating rheumatoid factor B. molecular mimicry of a streptococcal antigen and cardiac myosin C. a common variable immune deficiency D. a congenital abnormality

C.

A 46-year-old woman receives a non-T lymphocyte-depleted, allogeneic bone marrow transplant from a matched, unrelated donor. Immunosuppressive therapy with cyclosporine is started. One month later, she has fever. Cytolytic destruction of the skin, gastrointestinal tract, and liver is seen, with associated dermatitis, enteritis, and hepatitis. Which of the following best explains these findings? (A) C3b deposition (B) Cytomegalovirus infection (C) Graft-versus-host disease (D) Tolerance induction (E) Type I (immediate) hypersensitivity

E. Porins

A bacterium with __________________ will be able to transport scarce nutrients, ions, hydrophilic molecules and maltose. A. Teichoic acids B. Lipopolysaccharide C. Lipid A D. Periplasmic space E. Porins

D. Periplasmic space

A bacterium with an outer membrane will contain __________________ which makes it more resistant to anti microbials and is the site of active transport mechanisms. A. Teichoic acids B. Lipopolysaccharide C. Lipid A D. Periplasmic space E. Porins

B. Lose water Remember having a cell wall does not protect against plasmolysis, cells that have a cell wall undergo plasmolysis instead of crenation. Plasmolysis = contracting and detaching of plasma membrane from the cell wall

A cell exposed to a hypertonic environment will _____________ by osmosis A. Gain water B. Lose water C. Neither gain nor lose water D. Burst

A. Blue Because it had to go through the least amount of cycles to show fluorescence first?

A reference clinical lab received samples from three subjects with clinical symptoms UTI and bacteriuria. Quantitative detection by Real-Time PCR was done targeting uspA genes in genomic DNAs isolated from urine samples of these patients, to confirm if Escherichia Coli is the culprit and rapidly adjust antibiotic treatment accordingly. The results of the qPCR reaction are shown below. Which clinical sample(s) had the highest level of E.coli? A. Blue B. Red C. Green D. All three

D. All three

A reference clinical lab received samples from three subjects with clinical symptoms UTI and bacteriuria. Quantitative detection by Real-Time PCR was done targeting uspA genes in genomic DNAs isolated from urine samples of these patients, to confirm if Escherichia Coli is the culprit and rapidly adjust antibiotic treatment accordingly. The results of the qPCR reaction are shown below. Consider 40 cycles to be the cut-off for very low amount of target nucleic acid Which clinical sample(s) was/were positive for E.coli? A. Blue B. Red C. Green D. All three

D.

A small protein subunit used in a vaccine can fail to stimulate T-cell immunity because of: A Lack of glycosylation B Lack of conformation C Lack of carrier determinants D HLA-related unresponsiveness E Inherently insufficient antigen concentration.

D.

Cytomegalovirus remains one of the most important viral infections that usually crops up during the mid period post transplantation leading to substantial morbidity and mortality. Which one of the following scenario would be at low risk of transplant related infection with this virus? A) Seronegative recipient of seropositive organs B) Seropositive recipient of seronegative organs C) Seropositive recipient of seropositive organs D) Seronegative recipient of seronegative organs

A.

Cytotoxic T cells are rapid killers of infected target cells. Within minutes of the interaction of a cytotoxic T cell with a target cell, the program of apoptosis in the target cell is initiated. This rapid activity is a consequence of: A. The expression and packaging of perforin and granzymes in cytotoxic granules prior to target cell encounter B. The extremely rapid production of granzymes and perforin by cytotoxic effector cells upon encountering a target cell C. The extremely potent activity of perforins in poking holes in target cell membranes allowing entry of granzymes D. The efficient activity of granzymes in cleaving effector caspases leading to direct activation of apoptosis E. The large number of cytotoxic granules made and secreted by a single effector cytotoxic T cell

C. DiGeorge's syndrome

This the most clearly defined T-cell immunodeficiency and is also known as congenital thymus aplasta/hypoplasia, or immunodeficiency with hypoparathyroidism. The syndrome is associated with hypoparathyroidsim, cogenital heart disease, low set notched ears and fish shaped mouth. These defects results from abnormal development of the fetus (3rd and 4th pharyngeal pouch) during the 6th and 10th week of gestation when parathyroid, thymus, lips, ears and aortic arch are being formed. A. Selective IgA immunodeficiency B. X-linked hypo-gamma-globulinemia C. DiGeorge's syndrome

E. Aerobic respiration

Identify which bacterial metabolism pathway the following statement correlates to: Energy is generated by membrane proton pump, substrate level phosphorylation and NADH A. Entner-Doudoroff pathway B. Fermentation C. Glycolysis D. Proton motive force E. Aerobic respiration

C. Electron transport/oxidative phosphorylation

Identify which bacterial metabolism pathway the following statement correlates to: Final stage of respiration where ATP is formed A. Glycolytic or Embden-Meyerhof pathway B. Krebs cycle (TCA cycle) C. Electron transport/oxidative phosphorylation D. Pentose phosphate shunt E. Entner-Doudoroff pathway F. Glyoxylate cycle

E. Entner-Doudoroff pathway

Identify which bacterial metabolism pathway the following statement correlates to: Generates pyruvate and NADPH A. Glycolytic or Embden-Meyerhof pathway B. Krebs cycle (TCA cycle) C. Electron transport/oxidative phosphorylation D. Pentose phosphate shunt E. Entner-Doudoroff pathway F. Glyoxylate cycle

A. Glycolytic or Embden-Meyerhof pathway

Identify which bacterial metabolism pathway the following statement correlates to: Generates pyruvate molecules from oxidation of glucose A. Glycolytic or Embden-Meyerhof pathway B. Krebs cycle (TCA cycle) C. Electron transport/oxidative phosphorylation D. Pentose phosphate shunt E. Entner-Doudoroff pathway F. Glyoxylate cycle

B. Krebs cycle (TCA cycle)

Identify which bacterial metabolism pathway the following statement correlates to: Oxidative process by which pyruvate is decarboxylated to CO2 A. Glycolytic or Embden-Meyerhof pathway B. Krebs cycle (TCA cycle) C. Electron transport/oxidative phosphorylation D. Pentose phosphate shunt E. Entner-Doudoroff pathway F. Glyoxylate cycle

D. Pentose phosphate shunt

Identify which bacterial metabolism pathway the following statement correlates to: Produces 5-carbon sugars used in the biosynthesis of nucleic acids A. Glycolytic or Embden-Meyerhof pathway B. Krebs cycle (TCA cycle) C. Electron transport/oxidative phosphorylation D. Pentose phosphate shunt E. Entner-Doudoroff pathway F. Glyoxylate cycle

D. Proton motive force

Identify which bacterial metabolism pathway the following statement correlates to: Secretion of protons creates a proton gradient across membrane (chemiosmotic energy) A. Entner-Doudoroff pathway B. Fermentation C. Glycolysis D. Proton motive force E. Aerobic respiration

B. Fermentation

Identify which bacterial metabolism pathway the following statement correlates to: Simple organic end products (alcohols, acids) are formed from the anaerobic dissimulation of glucose A. Entner-Doudoroff pathway B. Fermentation C. Glycolysis D. Proton motive force E. Aerobic respiration

B. Catalase and SOD Negative Remember anaerobes respire anaerobically and are killed by oxygen

Indicate which combination (if any) would be used during oxygen metabolism as it relates to: Anaerobes (Obligate, strict) A. Catalase and SOD positive B. Catalase and SOD Negative C. Catalase and SOD +/-

A. Catalase and SOD positive Remember facultative anaerobes respire with Oxygen and ferment without oxygen

Indicate which combination (if any) would be used during oxygen metabolism as it relates to: Facultative Anaerobes A. Catalase and SOD positive B. Catalase and SOD Negative C. Catalase and SOD +/-

C. Catalase and SOD +/- Remember microaerophilics grow best at low concentrations of oxygen

Indicate which combination (if any) would be used during oxygen metabolism as it relates to: Microaerophilic A. Catalase and SOD positive B. Catalase and SOD Negative C. Catalase and SOD +/-

E. Both C and D

Resistance to Beta-lactam antibiotics is the result of A. Loss of the transport system B. Increased membrane permeability C. Lower affinity of the transpeptidases for the penicillin D. Enzymatic inactivation of the antibiotic E. Both C and D

B.

Rhesus hemolytic disease of the fetus and newborn involves: A IgE B Antibody to cell surface antigen C Soluble immune complexes D Cytokine release from T-cells E Stimulator antibodies

C. Affinity maturation in the germinal center Remember memory cells have already gone through affinity maturation in germinal center

Secondary responses involving memory B cells are more robust compared to the primary response and the antibodies generated have more affinity to the antigen because of A. Junctional diversity introduced by P and N nucleotides B. RAG1 and RAG2 genes C. Affinity maturation in the germinal center D. Class switching

Reactive Systemic Amyloidosis ( secondary amyloidosis)

Secondary to chronic inflammatory conditions - tuberculosis - bronchiectasis - chronic osteomyelitis - autoimmune diseases like Rheumatoid Arthritis - other causes : • renal cell carcinoma • Hodgkin lymphoma

B. Substrate Specific Porins (lamB)

Select the correct answer as it relates to the statement regarding Gram negative cell call: Outer membrane Bacteriophage lambda receptor A. Porins (Omp) B. Substrate Specific Porins (lamB) C. Ton-B dependent

B. Substrate Specific Porins (lamB)

Select the correct answer as it relates to the statement regarding Gram negative cell call: Outer membrane Facilitated diffusion of maltose A. Porins (Omp) B. Substrate Specific Porins (lamB) C. Ton-B dependent

C. Ton-B dependent

Select the correct answer as it relates to the statement regarding Gram negative cell call: Outer membrane Specific for diffusion of scarce, large molecules like Vitamin B12 A. Porins (Omp) B. Substrate Specific Porins (lamB) C. Ton-B dependent

A. Porins (Omp)

Select the correct answer as it relates to the statement regarding Gram negative cell call: Outer membrane Stabilizes mating of cells during conjugation A. Porins (Omp) B. Substrate Specific Porins (lamB) C. Ton-B dependent

A. Porins (Omp)

Select the correct answer as it relates to the statement regarding Gram negative cell call: Outer membrane Trimeric proteins that let through ions and small hydrophilic molecules A. Porins (Omp) B. Substrate Specific Porins (lamB) C. Ton-B dependent

B. Non-homologous, site-specific, specialized

Select the correct type of recombination as it relates to the statement below RecA-independent A. Homologous or generalized B. Non-homologous, site-specific, specialized C. Both

A. Homologous or generalized

Select the correct type of recombination as it relates to the statement below Recipient cell must express recombination enzymes A. Homologous or generalized B. Non-homologous, site-specific, specialized C. Both

B. Non-homologous, site-specific, specialized

Select the correct type of recombination as it relates to the statement below Specialized enzymes recognize specific nucleotide sequences and promote crossover events A. Homologous or generalized B. Non-homologous, site-specific, specialized C. Both

B. Non-homologous, site-specific, specialized

Select the correct type of recombination as it relates to the statement below Specific (att) sites; no sequence homology required A. Homologous or generalized B. Non-homologous, site-specific, specialized C. Both

E. Phosphotransferases

Sugar transport into bacteria is frequently facilitated by A. Acetyltransferase B. Neuraminidases C. Oxidases D. Penicillin-binding proteins E. Phosphotransferases

True

Sugars can be metabolized anaerobically via glycolysis and the TCA cycle. True/False

False: 1. NK cells do not require antigens to be presented in the context of MHC molecules. Their cytotoxicity is not antibody-dependent or MHC-restricted. True: 2. Signaling through CD80/86 and CD28 is important for naïve T cell activation. False: 3. Effector T cells actually downregulate CCR7 and upregulate other chemokine receptors such as CXCR3 and CCR5 that allow them to migrate to peripheral tissues. True: 4. Signaling through CD80/86 is important for effector T cell functions, including cytokine production and proliferation.

TRUE OR FALSE 1. NK cells require antigens to be presented in the context of MHC molecules. 2. Signaling through CD80/86 and CD28 is important for naïve T cell activation 3. Effector T cells express high levels of CCR7 [chemokine required for homing to lymph nodes] as opposed to naïve T cells 4. Signaling through CD80/86 is important for effector T cell functions

C.

What are the major effector molecules involved in type IV hypersensitivity reactions? A Antibodies B Complement components C Cytokines D Prostaglandins E 5-hydroxytryptamine (5-HT)

1. Substrate level phosphorylation B. Oxidative phosphorylation C. Photophosphorylation

What are the three ways ATP can be created?

C. DNA polymerase

What factor in the reaction is depicted by the green symbol marked as A? A. Reverse transcriptase B. Magnesium C. DNA polymerase D. cDNA E. DNA ligase

A.

What is a potential disadvantage of immunological protection using passive transfer of horse globulins? A Serum sickness B Irreversible protection [Incorrect] C Lack of antibody-mediated immune response D Type IV hypersensitivity reactions E Immunodeficiency.

A. Directs ribosome to start codon

What is the function of the Shine-Dalgarno sequence A. Directs ribosome to start codon B. Indicates the end of the protein synthesis process C. Recognizes the rho-dependent protein D. Is recognized by transcription factors

B. The thickness of the peptidoglycan layer

What makes a Gram stain differential? A. The presence of a capsule B. The thickness of the peptidoglycan layer C. The presence of teichoic aids D. The cytoplasmic membrane

B.

When T cells do not encounter their antigens in the secondary lymphoid tissue, they leave the tissue to get back into circulation. They do this by A. Undergoing apoptosis B. Following the sphingosine 1-phosphate gradient and upregulating S1₽ receptor C. Upregulating CD69 D. Undergoing activation and proliferation

A. A phenomenon called original antigenic sin

When individuals who have been infected with one variant of influenza virus are infected with a second or third variant, they make antibodies only against epitopes that were present on the initial virus. This is because of A. A phenomenon called original antigenic sin B. Short half life of anti-influenza virus antibodies C. Insufficient time for them to develop antibodies against the new variants D. New variant is not virulent

D. DNA microarrays

Which of the folloiwng techniques is more apporpiate for simultaneous detected of RNA from influenza viruses A/H1N1, A/H3N2, and A/H5H1 and influenza B virus from the same clinical sample? A. Western blot B. Ribotyping C. RLFP-PFGE D. DNA microarrays E. ELISA

B. Core polysaccharide

Which of the following components of the lipopolysaccharide (LPS) contains unusual heptose sugar A. O antigen B. Core polysaccharide C. Lipid A

C. Lipid A

Which of the following components of the lipopolysaccharide (LPS) is responsible for gram negative sepsis A. O antigen B. Core polysaccharide C. Lipid A

A. O antigen

Which of the following components of the lipopolysaccharide (LPS) is used for antigenic typing A. O antigen B. Core polysaccharide C. Lipid A

A. IL-10

Which of the following cytokines is NOT generally found in increased concentration in individuals with chronic inflammation? A. IL-10 B. TNF-alpha C. IL-1 D. IL-6 E. All of the answers are generally elevated in chronic inflammation

B. Suppression of mast-cell degranulation

Which of the following effects is NOT a result of histamine binding to histamine receptor H1? A. Intestinal smooth muscle contraction B. Suppression of mast-cell degranulation C. Increased vascular permeability D. Increased mucous secretion E. All of the answers result from histamine binding H1

D. Osmotic resistance

Which of the following is NOT a function of the plasma membrane? A. Transport and permeability barrier B. Biosynthesis of DNA and cell was components C. Energy transduction D. Osmotic resistance

B.

Which of the following is a non-organ-specific (systemic) autoimmune disease? A Myasthenia gravis B Systemic lupus erythematosus (SLE) C Hashimoto's thyroiditis D Pernicious anemia E Type I (insulin-dependent) diabetes mellitus

D. Increased clearance of immune complexes

Which of the following is least likely to lead to autoimmunity A. Some loss of suppressor T cells B. Release of sequestered self antigens C. Genetic predisposition D. Increased clearance of immune complexes

increased clearance of immune complexes

Which of the following is least likely to lead to autoimmunity?

E.

Which of the following is required for naïve T-cell activation? A. Expression of CD4+ or CD8+ B. Interaction with CD80, CD86, or ICOS-L C. Both antigen-specific TCR binding to MHC peptide and expression of CD4+ or CD8+ are correct. D. Both antigen-specific TC binding to MHC peptide and Interaction with CDS0. CD86, or ICOS-L are correct. E. Antigen specific TC binding to MHC, expression of CD4 or CD8 and interaction with CD80/CD86 or ICOS-L are all required

E. Cell to cell contact is required for conjugation to occur

Which of the following statements is correct about conjugation? A. Conjugation can occur without the production of sex pilus B. DNA-degrading enzymes in the extracellular medium would stop the process C. The bacterial cell must be in a "competent" state to undergo conjugation D. The DNA transferred can exist as plasmid (prophage) or encapsulated as viral particles (virions) E. Cell to cell contact is required for conjugation to occur

E. All

Which one of these can encode antibiotic resistance and virulence genes A. Plasmids B. Phases C. Transposons D. A and B E. All

E. All

Which one of these can exist integrated in the bacterial genome or as circular molecule? A. Plasmids B. Phases C. Transposons D. A and B E. All

D. Automated Ribotyping and PFGE (Pulse-Filled Gel Electrophoresis) What is the molecular basis for this test? What is it useful for?

Which technique is depicted in the following picture? A. Dot blot hybridization B. Real-time PCR C. Western blot D. Automated Ribotyping E. Agarose gel electrophoresis

E. IFN-gamma

While innate immune responses to all types of infections induce local inflammatory responses due to activation of blood vessel endothelial cells, some components of the innate response differ depending on the nature of the pathogen. In the case of intracellular bacterial or protozoan infections, tissue-resident dendritic cells and macrophages produce a cytokine that stimulates ILC cells to produce: A. IL-13 B. TNF-Alpha C. IL17 D. IL22 E. IFN-gamma

No

While on a backpacking trip you are bitten by a poisonous snake. The medevac comes to airlift you to the nearest hospital, where you receive human immunoglobin treatment (anti serum) against the poisonous snake venom. You recover from your snakebite and return home. One year later, during an environmental studies filed trip, you are bitten once again by the same type of snake. Please answer the following questions: Since you fully recovered from the first snake bite, are you protected from the effects of the poison this second time (i.e., did you develop adaptive immunity)?

B. Less sensitive Equally sensitive would mean no immunity developed at all

While on a backpacking trip you are bitten by a poisonous snake. The medial comes to airlift you to the nearest hospital, where you receive human immunoglobulin treatment (anti serum) against the poisonous snake venom. You recover from your snakebite and return home. One year later, during an environmental studies field trip, you are bitten once again by the same type of snake. Compared to the first snakebite, you are _________________ to the venom from the second bite. A. More sensitive B. Less sensitive C. Equally sensitive

B. Less sensitive Equally sensitive would mean no immunity developed at all ANSWER HAS CHANGED TO E. 2023

While on a backpacking trip you are bitten by a poisonous snake. The medial comes to airlift you to the nearest hospital, where you receive human immunoglobulin treatment (anti serum) against the poisonous snake venom. You recover from your snakebite and return home. One year later, during an environmental studies field trip, you are bitten once again by the same type of snake. Compared to the first snakebite, you are _________________ to the venom from the second bite. A. More sensitive B. Less sensitive C. Equally sensitive

No Remember antibodies neutralize the venom preventing the activation of adaptive immunity

While on a backpacking trip you are bitten by a poisonous snake. The medial comes to airlift you to the nearest hospital, where you receive human immunoglobulin treatment (anti serum) against the poisonous snake venom. You recover from your snakebite and return home. One year later, during an environmental studies field trip, you are bitten once again by the same type of snake. Since you fully recovered from the first snake bite, are you protected from the effects of the poison this second time ( I.e. did you develop adaptive immunity)? Yes or No

When individuals who have been infected with one variant of influenza virus are infected with a second or third variant, they make antibodies only against epitopes that were present on the initial virus. This is because of: a. A phenomenon called original antigenic sin b. Short half life of anti-influenza virus Ab c. Insufficient time for them to develop Ab against new variants d. New variant is not virulent

a. A phenomenon called original antigenic sin

cAMP/CAP promotes binding of RNA pol to promoter I.e., cAMP/CAP is an _________ a. Activator b. Inducer c. Repressor d. Operator e. Blocker

a. Activator

A person is given an attenuated antigen as a vaccine. When the person asks what was given in the vaccine, how should the nurse respond? The antigen is: a. Alive, but less infectious b. Mutated, but highly infectious c. Normal, but not infectious d. Inactive, but infectious

a. Alive, but less infectious

When trying to distinguish between an infectious disease and noninfectious disease, what is the hallmark symptom for most infectious diseases? a. Fever b. Jaundice c. Vomiting d. Pain

a. Fever

An immunologist is discussing endotoxin production. Which information should the immunologist include? Endotoxins are produced by: a. Gram-negative bacteria b. Gram-positive bacteria c. Gram-negative fungi d. Gram-positive fungi

a. Gram-negative bacteria

Which of the following cytokines is NOT generally found in increased concentrations in individuals with chronic inflammation? a. IL-10 b. TNF-alpha c. IL-1 d. IL-6 e. All of the answers are generally elevated in chronic inflammation

a. IL-10

When bacterial pathogens enter a patient's body, they can defend themselves from an immune response by: a. Producing capsules b. Phagocytosis c. Retreating d. Developing antibodies

a. Producing capsules

In the gram stain sequence, which color do the gram negative cells become before decolorization with alcohol? a. Purple b. Red c. Brown (color of iodine) d. Clear

a. Purple

Arthus reaction

area of tissue necrosis resulting from acute immune complex vasculitis.

Type III hypersensitivity reactions are induce by: a. IgE Ab b. Antigen - Ab (IgG) complexes c. T cells d. IgG/IgM Ab against cell surface antigens

b. Antigen - Ab (IgG) complexes

In spring of 2009, a H1N1 virus with genes with North american swine, eurasian swine, humans and birds emerged to infect people and quickly spread, causing a pandemic. This was mainly due to: a. A phenomenon called original antigenic sin b. Antigenic shift c. Insufficient time for them to develop Ab against new variants d. Antigenic drift

b. Antigenic shift

The immune response is a dynamic process that initiates with an antigen-independent response, which becomes more focused and powerful as it develops antigen specificity. Once the adaptive immune system develops, a single type of response is capable of eliminating any type of antigen. a. True b. False

b. False

A 30-year-old female presents to her primary care provider reporting fatigue, excessive sweating, and increased appetite. Physical examination reveals protruding eyes, and laboratory testing reveals hyperthyroidism secondary to autoantibody production. This disorder falls into the category of type _____ hypersensitivity. a. I b. II c. III d. IV

b. II

A 5-year-old male presents with low-set ears, a fish-shaped mouth, and involuntary rapid muscular contraction. Laboratory testing reveals decreased calcium levels. Which of the following diagnosis is most likely? a. B lymphocyte deficiency b. T lymphocyte deficiency c. Combined immunologic deficiency d. Complement deficiency

b. T lymphocyte deficiency

While innate immune responses to all types of infections induce local inflammatory responses due to activation of blood vessel endothelial cells, some components of the innate response differ depending on the nature of the pathogen. In the case of intracellular bacterial or protozoan infections, tissue-resident dendritic cells and macrophages produce a cytokine that stimulates ILC cells to produce: a. IL-13 b. TNF-𝛂 c. IL-17 d. IL-22 e. IFN-Ɣ

b. TNF-𝛂 e. IFN-Ɣ

DNA replication is semiconservative because the ___ strand will become half of the ___ molecule. a. RNA, DNA b. Template, finished c. Sense, mRNA d. Codon, anticodon

b. Template, finished

22 yo presents to the clinic with persistent cough, high fever, inflammatory infiltrate on CXR and exposure to a roommate with pneumonia symptoms who was treated successfully with macrolide abx. A sputum gram stain shows WBC but no organisms. What is the most likely explanation for no organisms seen in the gram stain? a. It is probably a viral infection b. The causal organism lacks a cell wall c. The presence of a polypeptide capsule blocks gram staining

b. The causal organism lacks a cell wall

Individuals with peanut allergies can exhibit symptoms following exposure to the peanut allergen. These symptoms can include a runny nose, skin rxn like hives, itchy mouth and throat, digestive problems like cramps, diarrhea or vomiting, and SOB or wheezing as a result of: a. Systemic production of inflammatory mediators causing response in many tissues b. The presence of mast cells with pre-bound IgE in all mucosal tissues c. The simultaneous exposure of skin, oral mucosa, throat, an GI tract to an ingested allergen d. The high concentrations of histamine present in pre-stored mast cell granules e. The presence of high concentrations of IgE in the circulation

b. The presence of mast cells with pre-bound IgE in all mucosal tissues

During rho independent transcription termination: a. The rho factor recognizes the Shine Dalgarno sequence on the RNA molecule b. The rho factor binds to the end of the RN chain and slides along the strand towards the polymerase c. A hairpin loop forms that is recognized by the rho factor d. The rho factor employs energy to interchange sigma factors in the RNApol

b. The rho factor binds to the end of the RN chain and slides along the strand towards the polymerase

mRNA is formed by ___ of a gene on the DNA template strand. a. Transformation b. Transcription c. Replication d. Translation e. Translocation

b. Transcription

An example of a repressible operon regulated by attenuation is: a. Lac operon b. Trp operon c. Synthesis of ribosomal proteins d. Heat shock protein expression

b. Trp operon

When the immunologist says that pathogens possess virulence, what does virulence mean? a. Spreads from one individual to others and causes disease b. Induces an immune response c. Causes disease d. Damages tissue

c. Causes disease

When an immunologist teaches about the relationship that benefits the organism but causes no harm to the host, the immunologist is describing which of the following? a. Symbiosis b. Mutualism c. Commensalism d. Pathogenicity

c. Commensalism

Which information indicates a good understanding of bacterial vaccines? Most bacterial vaccines contain: a. Active bacteria b. Synthetic bacteria c. Dead bacteria d. Bacterial toxins

c. Dead bacteria

A patient presents with poison ivy on the extremities, face, and buttocks. This condition is an example of: a. Anaphylaxis b. Serum sickness c. Delayed hypersensitivity d. Viral disease

c. Delayed hypersensitivity

Radioallergosorbent test (RAST): a. Uses complement proteins b. Uses IgG Ab against a specific allergen c. Detects IgE Ab against a specific allergen in the pt's serum d. Uses enzymes for detecting the bound allergen

c. Detects IgE Ab against a specific allergen in the pt's serum

This the most clearly defined T-cell immunodeficiency and is also known as thymic aplasia/hypoplasia, or immunodeficiency with hypoparathyroidism, congenital heart disease, low set notched ears and fish shaped mouth. These defects result from abnormal development of the fetus (3rd and 4th pharyngeal pouch) during the 6th to 10th week of gestation when parathyroid, thymus, lips, ears, and aortic arch are being formed. a. Selective IgA immunodeficiency b. X-linked hyper-gamma-globulinemia c. DiGeorge's syndrome

c. DiGeorge's syndrome

A 50-year-old female experiences decreased blood pressure, decreased oxygen delivery, cardiovascular shock, and subsequent death. A complication of endotoxic shock is suspected. Which of the following is the most likely cause? a. Gram-positive bacteria b. Fungi c. Gram-negative bacteria d. Virus

c. Gram-negative bacteria

The mechanism of competence of gram negative bacteria is characterized by: a. Homologous or heterologous, double stranded DNA enters the cell b. Transformasome complex needs to be assembled through the thick peptidoglycan layer c. Homology and thus potential for recombination into the host genome is assured during the DNA uptake process in some gram negative species d. RecA recognizes methylation patterns to determine outcome of the exogenous DNA

c. Homology and thus potential for recombination into the host genome is assured during the DNA uptake process in some gram negative species

Yersinia pestis, the causative agent of the bubonic plague, has multiple mechanisms of immune evasion. This gram-negative bacterium is transmitted from fleas (body temperature, 26 degrees celsius) to humans (body temperature 37 degrees celsius) by flea bites. Studies have shown that the lipopolysaccharide (LPS) produced by Y. pestis grown at 37 degrees celsius is about 10-fold less potent at stimulating TLR4 signaling than is the Y. pestis LPS from bacteria grown at 26 degrees celsius. When these two forms of Y. pestis LPS are compared for their abilities induce responses from human macrophages. One would expect that the 26 degree celsius Y. pestis LPS would result in: a. Increased production of antimicrobial peptides b. Reduced production of IL-10 c. Increased production of TNF-𝝰 and IL-6 d. Reduced production of Type I interferons e. Increased activation of the inflammasome

c. Increased production of TNF-𝝰 and IL-6

When the immunologist says that pathogens possess infectivity, what is the immunologist explaining? Infectivity allows pathogens to: a. Spread from one individual to others and cause disease b. Induce an immune response c. Invade and multiply in the host d. Damage tissue

c. Invade and multiply in the host

CRISPR-CAS9 recombination: a. Imparts specificity to the process of anti-viral antibody production b. Allows for chromosomal integration of non-homologous exogenous DNA c. Is based on recognition and cleavage of exogenous DNA by a library of DNA sequences d. Mechanisms for integration of viral DNA in the host cell genome

c. Is based on recognition and cleavage of exogenous DNA by a library of DNA sequences

An atpic person was exposed to an allergen and assume that he will be sensitized. He is subjected to a skin test after ten days. Predict the outcome if Fc fragments of human IgE (half life 20 days) was injected at the same site immediately after antigen exposure but prior to skin test. a. No reaction would occur because the Fc fragments would interact with the allergen and prevent it from gaining access to the sensitized mast cells b. No reaction would occur because the Fc fragments would interact with the IgE antibodies making their antigen-binding sites unavailable for binding to antigen c. No reaction would occur because the Fc fragments would interact with Fc receptors on mast cells d. The reaction would be exacerbated d/t the increased local concentration of IgE Fc fragments e. The reaction would be exacerbated d/t the activation of complement

c. No reaction would occur because the Fc fragments would interact with Fc receptors on mast cells

During low osmolarity conditions, ________ is preferentially expressed. a. Sex pili b. OmpC c. OmpF d. TonB dependent proteins

c. OmpF

Hepatitis B virus infection is usually acute and self-limited, chronic hepatitis of fulminant hepatitis. However, a nonsense mutation in the Hep e antigen correlated with fulminant hepatitis. Which of the following techniques would be most appropriate to test this possibility in a clinical sample? a. DNA microarrays b. Ribotyping c. PCR followed by sequencing d. Southern blot

c. PCR followed by sequencing

After studying about viruses, which information indicates the student has a good understanding of viruses? Viruses: a. Contain no DNA or RNA b. Are capable of independent reproduction c. Replicate their genetic material inside host cells d. Are easily killed by antimicrobials

c. Replicate their genetic material inside host cells

A nurse recalls an example of an immune-complex-mediated disease is: a. Bronchial asthma b. Contact dermatitis c. Serum sickness d. Rheumatoid arthritis

c. Serum sickness

An infant is experiencing hemolytic disease of the newborn. Which of the following would the nurse expect to find in the infant's history and physical? a. The mother was exposed to measles. b. The father was exposed to Agent Orange. c. The baby is Rh positive. d. The baby was born 6 weeks prematurely.

c. The baby is Rh positive.

The genes that code for proteins involved in catabolite repression are regulated by? a. Covalent modifications b. Proteins that detect a signal c. The levels of cAMP in the media d. Are always on since they have a housekeeping function

c. The levels of cAMP in the media

During transcription regulation via Attenuation, a. A group of operons is controlled by a common regulator (e.g., alternative sigma factors) b. Transcription has occurred but translation start is regulated c. Transcription is allowed to proceed only when there are insufficient levels of amino acids d. Adjacent, function-related genes are transcribed as a single mRNA molecule

c. Transcription is allowed to proceed only when there are insufficient levels of amino acids

Protein is formed by ___ of a nucleotide sequence encoded on the mRNA molecule. a. Transcription b. Replication c. Translation d. Transformation

c. Translation

Trp operon is regulated by: a. Tryptophan binding to repressor when it is in high levels and inactivating it b. Attenuation c. Tryptophan binding to repressor when it is in high levels and activating it d. Terminating transcription when tryptophan levels are low e. Both B and C

e. Both B and C

Resistance to beta-lactam abx is the result of: a. Loss of the transport system b. Increased membrane permeability c. Lower affinity of the transpeptidases for the penicillin d. Enzymatic inactivation of the Abx e. Both C and D

e. Both C and D

Which of the following statements is correct about conjugation? a. Conjugation can occur without the production of a sex pilus b. DNA-degrading enzymes in the extracellular medium would stop the process c. The bacterial cell must be in a "competent" state to undergo conjugation d. The DNA transferred can exist as plasmid (prophage) or encapsulated as viral particles (virions) e. Cell to cell contact is required to conjugation to occur

e. Cell to cell contact is required to conjugation to occur

_____ consists of three autosomal recessive conditions. The most frequent condition is caused by mutations in β2 integrin gene (CD18); following leukocyte activation, β2 integrins mediate adhesion to inflamed endothelium expressing cognate ligands. Given that neutrophils are not able to reach infected tissues, the disease renders the individual susceptible to bacterial and fungal infections. a. DiGeorge Syndrome b. SCID c. Selective IgA d. XLA e. LAD

e. LAD

-lactamases confer antibiotic resistance by: a. Altering Abx permeability b. Altering penicillin-binding proteins c. Altering 70S ribosome structure d. Modifying cellular RNA polymerase e. Modifying Abx structure

e. Modifying Abx structure

Sugar transport into bacteria is frequently facilitated by: a. Acetyltransferase b. Neuraminidases c. Oxidases d. Penicillin -binding proteins e. Phosphotransferases

e. Phosphotransferases

A bacterium with ____ will be able to transport scarce nutrients, ions, hydrophilic molecules and maltose. a. Teichoic acids b. Lipopolysaccharide c. Lipid A d. Periplasmic space e. Porins

e. Porins

Function of mast cell mediator factors

responsible for Immediate response & late-phase reaction

AL (amyloid light chain) protein

• It is produced by plasma cells and is made up of complete immunoglobulin (Ig) light chains • It is associated with some form of monoclonal B-Cell proliferation (Plasma cell myeloma)

Amyloid transthyretfn (ATTR)

• Mutations in the gene encoding transthyretin result ii^ the production of a protein that aggregate and form amyloid deposits. • the protein is structurally normal, but it accumulates at high concentrations • The resultant disease's are called familial amyloid polyneuropathies.

Localized amyloidosis

• Primary associated with some immunocyte dyscrasia • Secondary occurs as a complication of an underlying chronic inflammatory or tissue destructive process

Systemic (generalized) amyloidosis

• Primary associated with some immunocyte dyscrasia • Secondary occurs as a complication of an underlying chronic inflammatory or tissue destructive process

Genetic predisposition to SLE

• There is a higher incidence for monozygotic twins than in dizygctic twins • Family members have an increased risk of developing SLE, and up to 20% of clinically unaffected first-deg^ee relatives may reveal autoantibodies. • There is a positive association between SLE and class II HLA genes, particularly a their HLA-DQ locus. • Some lupus patients (about 6%) have inherited deficiencies of complement components. • Lack of complement presumably impairs removal of immune complexes from the circulation and favors tissue deposition, giving rise to tissue injury • The Clq component of complement is involved in phagocytosis of apoptotic cells, and its deficiency may lead to persistence of these cells and, hence, of nuclear antigens with the development of ANAs.

Hereditary or familial amyloidosis

• constitutes a heterogeneous group, with several distinctive patterns of organ involvement.

Systemic lupus erythematosus (SLE)

• multi-system autoimmune disease • remitting and relapsing disease • acute or insidious onset • involve virtually any organ in the body • skin, kidneys, serosal membranes, joints, and heart • Immunologically ➡ antinuclear antibodies (ANAs). • strong (approximately 9: 1) female1 preponderance • usual onset is in the second or third decade of life

Several prisoners are experiencing symptoms of tuberculosis. A tuberculin reaction test was ordered. This test is an example of type _____ hypersensitivity. a. I b. II c. III d. IV

d. IV

Which information would indicate more teaching is needed regarding hypersensitivity reactions? Type _______ hypersensitivity reactions involve an antibody response. a. I b. II c. III d. IV

d. IV

A. Lag phase

A bacteria utilizes available glucose in the medium and now is transferred to new medium containing galactose. Which phase corresponds to this transition process? A. Lag phase B. Log phase C. Stationary phase D. Death phase

Factors involved in the pathogenesis of autoimmune diseases

1- Breakdown of self-tolerance 2- Genetic Factors 3- changes in tissues induced by infections or injury

False

Anaerobic respiration is as efficient as aerobic respiration? True/False

A. Bacterial

Double stranded, closed molecule A. Bacterial B. Eukaryotic C. Both

B.

------------- expressed by Th cells will bind to it's appropriate receptor on DC thereby increasing the expression of costimulatory molecules like CD80/86 or B7. A. IL-2 B. CD40 L C. MHC I or Il D. CD21

D.

-------------- is the cytokine that is absolutely necessary for the proliferation and differentiation of both Tc and Th cells. A. IL-4 B. IL-5 C. G-CSF D. IL-2

What makes gram stain differential? a. The presence of a capsule b. The thickness of the peptidoglycan layer c. The presence of teichoic aids d. The cytoplasmic membrane

b. The thickness of the peptidoglycan layer

Aß amyloid (Amyloid beta)

• Aß protein is derived from a much larger transmembrane glycoprotein called amyloid precursor protein (APP) by the action of proteolytic enzymes; alfa & beta secretase • Aß circulates in the plasma, CSF & brain interstitial fluid • Aß s found in the cerebral lesions of Alzheimer disease. • Plays a central role in the development of Alzheimer disease • Aß constitutes the core of cerebral plaques and the amyloid deposits in cerebral blood vessels of patients with Alzheimer disease • It is unresolved how Aß amyloid accumulates in the CNS and subsequently initiate Alzheimer disease. • Some researchers found that Aß amyloid may competes with insulin for binding sites on insulin receptors and thus impairing glucose metabolism in the brain

Antinuclear antibodies

• Increased generation or defective clearance of nuclear antigens released from apoptotic cells, Together with the failure of T & B- cell tolerance to these self-antigens • The molecular mechanisms or failure of tolerance remain unknown

genetic Factors of autoimmune diseases is supported by

• Inheritance of various susceptibility genes • run in families • Greater incidence of the same disease in monozygotic than in dizygotic twins . • Several autoimmune diseases are linked with the HLA locus, especially class II alleles (HLA-DR/DQ). - The frequency of a disease in individuals with a particular HLA allele, compared to individuals who do not inherit that allele, is called the relative risk (risk ratio)(RR)

AA (amyloid-associated) protein

• Is a protein derived from a larger serum precursor called serum amyloid- associated protein (SAA) that is synthesized in the in the liver. • is associated with chronic inflammatory disorders • The production of SAA protein is increased in inflammatory states as part of the "acute phase response", in which IL1 and IL6 (secreted by neutrophils & macrophages) stimulate the liver to produce larger amount of SAA protein • The increased production of SAA protein is not sufficient to generate amyloid deposits. • SAA is normally degraded to soluble end products by macrophage- derived enzymes. • Defective proteolysis may produce misfolded, incomplete leading to aggregation and deposition as AA fibrils.

Effect of amyloids on the Heart

- Amyloid deposits are typically found throughout the myocardium, beginning between myocardial fibers and eventually causing their pressure - atrophy Leading ton cardiomyopathy with heart failure - * familial conditions* in which the amyloid deposits consist of mutants of normal proteins (e.g. transthyretin in familial amyloid polyneuropathies) - Amyloidosis of the adrenals, thyroid, and pituitary is common but without apparent disturbance of function - Modular depositions in the tongue may produce macroglossia. - Amyloid ß protein associated with Alzheimer disease - Familial conditions in which the amyloid deposits consist of mutants of normal proteins (e.g. transthyretin in familial amyloid polyneuropathies)

Pathogenesis of Amyloid Deposition

- Amyloidosis is a disorder of protein misfolding - More than 20 different proteins can aggregate to form the amyloid - Amyloid is composed of nor-branching fibrils, 7.5 to 10 nm in diameter, each formed of ß-sheet polypeptide chains that are wound together - The dye Congo red is commonly used to identify amyloid desposits in tissues. - Congo red dye binds to the amyloid fibrils and produces a red green birefringence

Antibody mediated Diseases (Type II Hypersensitivity)

- Caused by antibodies ➡ IgG or less freq. IgM - Antidodics are directed against antigens on the surface of cells or other tissue components - The antigens may be normal molecules intrinsic to cell membranes or extracellular matrix, or they may be *adsorbed exogenous antigens* (e.g., a drug metabolite)

characterized of Sjögren Syndrome

- Dry eyes ( keratoconjunctivitis sicca) and dry mouth (xerostomia) resulting from immune-mediated destruction of the lacrimal & salivary glands - It is caused by an autoimmune T-cell reaction against an unknown self antigen(s) expressed in these glands, or immune reactions against the antigens of a virus that infects the tissues. - The autoimmune mechanism is evidenced by the presence of ANAs and RF (even in the absence of associated RA). - However, there is no evidence that the autoantibodies cause primary tissue injury, - the disease is probably initiated by a loss of tolerance in the CD4+ T-cell - Approximately 25% of the patients develop extra-glandular disease affecting the CNS, skin, - kidneys, and muscles. Renal lesions take the form of mild interstitial nephritis - Glomerulonephritis is rare.

Effects of Amyloidosis

- Histologically, the amyloid deposition is always extracellular and begins between cells, often closely adjacent to basement membranes. - The clinical manifestations of amyloidosis depends on the organ involved Kidney

Complement & Fc receptor mediated inflammation

- Leukocytes are activated by engagement of Fc receptors, which recognize the IgG antibodies which are bound to the antigen on the cell membrane or ECM (fixed tissue ) - Antibodies bound to cellular or tissue antigens activate the complement system by the classical pathway. Products of complement activation recruit neutrophils and monocytes, triggering inflammation in tissues

Effect of amyloidosis on the Liver

- Massive enlargement (as much as 9000 gm) - Extremely pale grayish, and waxy on both the external surface and the cut section - Histologically, amyloid deposits first appear in the space of Disse and then progressively enlarge to encroach on the adjacent hepatic parenchyma and sinusoids .The trapped liver cells undergo compression atrophy and are eventually replaced by sheets of amyloid - Normal liver function may be preserved even in the setting of severe involvement.

Types of Th1 ( phases of Type IV Hypersensitivity)

- Memory cells remain in the circulation or tissues for years - Effector CD4+T cells secrete *IL2* & interferon gamma ( IFN )which Is the most potent *macrophage-activator* - Activated macrophages secrete *IL12 *which stimulate more CD4+ cells that Secret *IL-2 & interferon gamma* which in turn activate more macrophages, thus mediating the immune response

Changes in tissues induced by infections or injury

- Microbes may induce autoimmune reactions by several mechanisms: (1) Viruses and other microbes such as* streptococci* and *Klebsiella organisms* may share cross-reacting epitopes with self- antigens, such that responses to the microbial antigen may attack self-tissues - This phenomenon is called *molecular mimicry* - Example : *rheumatic heart disease*, in which an immune response against *streptococci* cross-reacts with cardiac antigens (2) Microbial infections with resultant tissue necrosis and inflammation *cause up regulation of co-stimulatory molecules on resting APCs in tissue*, thus favoring a breakdown of T-cell Energy and subsequent T-cetl activation. (3) The display of tissue antigens may be altered by infections and other triggers. (4) Local tissue injury for any reason may lead to the release of self- antigens and autoimmune responses.

Mechanisms of Tissue Injury

- Most of the systemic lesions are mediated by immune complexes (type III hypersensitivity). - DNA/anti-DNA complexes can be detected in the glomeruli, - Autoantibodies against red cells, white cells, and platelets promote destruction and phagocytosis of these cells (type II hypersensitivity). - Nuclei of damaged cells react with ANAs, lose their chromatin pattern, and become homogeneous, to produce so-called *LE bodies* or *hematoxylin bodies*. - An in vitro correlate of this is the* LE cell*, a neutrophil or macrophage that has engulfed the denatured nucleus of another injured cell.

Mechanism of Type III Hypersensitivity (Immune Complex Diseases)

- Occurs when there is an excess of antigen - Solvent Ag that are not bound to cell surface (which the case in type II hypersensitivity) Ag bind Ab ➡ formation of Immune complexes of different sizes - *Large complexes* (typically formed in antibody excess) are rapidly removed from the circulation *by macrophages in the spleen * and liver therefore usually harmless - Macrophages have difficulty in disposal of small immune complexes - *Small immune complexes* bound to site of deposition are more capable of interacting with complement - inducing an inflammatory response and tissue damage as a result of the action of *cleaved complement C3a & C5a* which mediate release of granules from mast cells (histamine)and attract neutrophils and macrophages (lysosomal action) - These small immune complexes insert themselves into *small blood vessels, Joint and glomeruli*

Pathogenesis of AIDS

- The two major targets of HIV infection are the immune system and the CNS - IN immune system, the main target for HIV is CD4+ T Lymphocytes & other CD4+ cells, particularly macrophages - The entry of H IV into cells requires the CD4 molecule, which acts as a high-affinity receptor for the HIV virus. However, The HIV must also bind to other cell surface molecules {co- receptors} to facilitate cell entry. - Inside the cell, HIV (RNA virus) undergoes reversed transcription (formation of Complementary DNA "cDNA", from the viral RNA) ➡ proviral DNA - In dividing T cells (in physiologic responses to infections and other stimuli) the cDNA enters the nucleus and becomes integrated into, the host genome - After Integration, the provirus may remain non-transcribed for months or years (latent infection) alternatively, proviral DNA may be transcribed to form complete viral particles that bud from the cell membrane ( productive infections) associated with extensive viral budding, lead to cell death - Initially, HIV infects T cells and macrophages directly or is carried to these cells by Langerhans cells. - Viral replication in the regional lymph nodes leads to viremia and widespread seeding of lymphoid tissue. - The viremia is controlled by the host immune response , and the patient then enters a phase of clinical latency. During this phase, viral replication in both T cells and macrophages continues unabated, but there is some.immune control of virus, - There continues a gradual lerosion of CD4+ cells by productive infection. - Ultimately, CD4+ cell numbers decline and the patient develops clinical Symptoms of full-blown AIDS. - Macrophages are also parasitized by the virus early; they are not lysed by HIV and they transport the virus to tissues, particularly the brain.

AMYLOIDOSIS

- Variety of condition in which normally soluble proteins become insoluble and are deposited in extracellullar spaces of various organs or tissues, disturbing normal function - These insoluble proteins are called amyloids - The amyloids are produced by the aggregation of misfolded proteins (which are soluble in their normal folded configuration) - Amyloid = starch like (contains sugar groups) - Amylose = starch

common clinical manifestations of type III - hypersensitivity

- Vasculitis - Arthritis - Glomerulonephritis

Opsonization and phagocytosis

- When circulating cells, such as erythrocytes or platelets, are coated (opsonized) with autoantibodies, with or without complement proteins, the cells become targets for phagocytosis by neutrophils and macrophages (Norma cell like erythrocytes or platelets - for some reason, a protein (Ag) binds to the cell. This protein Ag is targeted by IgG. Ab). - formation of antibody -antigen complex ➡ complement activation by the classic pathway - Phagocyte (macrophage or neutrophils) have receptors for Fc portion of IgG & receptors for C3b complement component and use these receptors to phagocytose the opsonized cells - Opsonized cells are usually eliminated in the spleen ➡ Splenomegaly

Explain Localization of immune in kidney and joints

- by the high hemodynamic pressures associated with the filtration function of the glomerulus and the synovium.

Primary Amyloidosis

- immunocyte Dyscrasia's with Amyloidosis - Usually systemic in distribution and is of the AL type (amyloid light chain) - The best example is amyloidosis associated with multiple myeloma (malignant neoplasm of plasma cells which secrete secrete either the γ or K light chain)

Amyloidosis of the kidney

- is the most common and most serious - The amyloid deposits are found principally in the glomeruli - At first there is focal deposits within the mesangial matrix and diffuse or nodular thickenings of the basement membranes of the capillary loops. - With progression, the deposition involves the capillary lumina and eventually leads to total obliteration of the vascular tuft

Mechanism of Immediate (type I) hypersensitivity

- mediated by *IgE* - Exposure to allergen like pollens, house dusts animal dander or penicillin - Sensitization occurs when antigen makes contact with the tissue - antigen is taken up by antigen presenting cells (macrophage ) - Ag is processed and expressed on the surface of the cell in association with class 2 MHC - Ag is presented to the *CD4 + Th2 cell* - Reaction between T cell and the Ag presenting cell - TH - cell secretes cytokines which stimulate B- cells to proliferate , differentiate into Plasma cells - Plasma cells secrete IgE - IgE molecules attach to receptors on nearby mast cells - Once attach to the mast cells, IgE can survive for many weeks - individual now sensitized to the Ag - When exposed to Ag for second time, the Ags bind to the IgE antibodies on the mast cells - To trigger a response. Two IgE molecules should react with antigen - Within seconds of the reaction, mast cells release their granules which contain histamine and other mediators that trigger different symptoms like capillary dilatation, bronchospasm, mucus secretion, pain & itching

Local Immune Complex Disease

- model of local immune complex diseases is the *Arthus reaction* - this reaction produced by injecting antigen into the skin of previously immunized animal (preformed antibodies against antigen present in the circulation). - *Because of the initial antibody excess* immune complexes are formed as antigen diffuses into the vascular wall - these are precipitated at the site of injection and trigger the same inflammatory reaction and histologic appearance as in systemic immune complex disease. - Arthus lesions evolve over few hours and reach peak 4 to 10 hours after injection - when the injection site develops *visible edema* with severe *hemorrhage* followed by *ulceration*

Local reactions (hypersensitivity I)

- occur when the antigen is confined to particular site, such as: 1- skin by direct contact, causing urticaria 2- GIT by ingestion, causing diarrhea 3- lung by inhalation; causing bronchoconstrictio

Causes of immediate response

1- *Histamine* - released within seconds or minutes of activation. - Causes vasodilation, increased vascular permeability, smooth muscle contraction and increased secretion of mucus. 2- *Adenosine* - Causes bronchoconstriction and inhibits platelet aggregation 3- *Prostaglandin D2 (PGD2)* - causes intense bronchospasm as well as increased mucus secretion. 4- *Leukotrienes C4 and D4 (LTC4, LTD4)* - most potent vasoactive and spasmogenic agents - active than histamine in increasing vascular permeability and causing bronchial smooth muscle contraction. 5- *LTB4* - highly chemotactic for neutrophils, eosinophil, and monocyte 6- *leukotriene B4 (LTB4)* - highly chemotactic for neutrophils , eosinophils and monocyte

Classification of Amyloidosis

1- Systemic (generalized ) 2- Localized 3- Hereditary or familial amyloidosis

Examples of Immune Complex-Mediated Diseases (type III hypersensitivity)

1- Systemic lupus erythematosus (SLE) - Nuclear antigen - Manifestation : nephritis , skin , lesions arthritis 2- Poststreptococcal glomerulonephritis - Streptococcal cell wall antigen(s) - Manifestations : nephritis 3- Polyarteritis nodosa - Hepatitis B virus antigen - Manifestations : systemic vacuities 4- Reactive arthritis - Bacterial antigens (Yersinia ) - Manifestations : acute arthritis 5- Serum sickness - Different proteins such as foreign serum protein - Manifestations : arthritis , vasculitis , nephritis 6- Arthus reaction (experimental) - Different foreign proteins - Manifestations : cutaneous vasculitis 7- Farmar's lung - Inhaled antigens (mouldy hay dust ) - Manifestations : alveolar inflammation 8- Henoch-Schönlein purpura - Unknown (respiratory pathogen ) - Manifestations : purpura glomerulonephritis

Types of Immediate hypersensitivity reaction

1- Systemic reaction or 2- local reaction. - determined by the route of antigen exposure.

Diseases associated with type II hypersensitivity occur bycomplement and Fc receptor mediated inflammation

1- Vasculitis caused by ANCA (Anti Neutrophilic Cytoplasmic Antibody) - The target AG is *Neutrophil granule proteins* released from activated neutrophils - Lead toVasculitis (inflammation of blood vessels) 2- Goodpasture syndrome - The target Ag is the *type 4 collagen in the basement membrane of glomeruli & alveoli* ➡ damage to the capillary basement membrane of the glomeruoli and alveoli - This leads to *Proteinuria* (protein in the urine due to increased permeability of the glomerular basement membrane) *hemoptysis* (Coughing of blood) 3- Acute rheumatic fever - Target Ag is group A streptococci which has similar antigenic properties as some tissue like heart & joints - antibody cross-reacts with myocardial antigen - leads to Myocarditis, arthritis

mast cell mediator factors

1- histamine 2- adenosine 3- PGD2 4- LTC4 , LTD4 5- LTB4 6- TNF and chemokine 7- IL-13

Organs affected by SLE

1. *Acute necrotizing vasculitis* • affecting small arteries and arterioles in any tissue. • fibrinoid deposits within vessel walls containing antibody, DNA, complement fragments, and fibrinogen; a transmural and perivascular leukocytic infiltrate is also frequently present. In chronic stages, vessels show fibrous thickening with luminal narrowing 2. *Glomerulonephritis in SLE* involves deposition of DNA/anti-DNA complexes within the glomeruli 3. *The skin* is involved in the majority of patients; a characteristic erythematous or maculopapular eruption over the malar eminencies and bridge of the nose ("butterfly pattern") is observed in about half. • Exposure to sunlight (UV Sight) exacerbates the erythema (so-called photosensitivity), and a similar rash may be present elsewhere on the extremities and trunk, frequently in sun-exposed areas. 4. *Join t involvement* is frequent but is usually mild 5. *CNS involvement* is very common • angiopathy may result from thrombosis caused by antiphospholipid antibodies causing ischemia or multifocal cerebral micro-infarcts 6-* Heart Involvement* • involvement of the pericarditis, • myocarditis • valvular lesions, called Libman-Sacks endocarditis

Pathogenesis of RA

1. *Clear genetic predisposition* - Increased frequency among first-degree relatives and in monozygotic twins - Associations of HLA-DR4 with RA. 2.* environmental factors* - the initiating agents and the precise interplay between genetic and environmental factors are not yet understood - It is initiated, in a genetically predisposed individual, by activation of CD4+ helper T cells responding to some arthritogenic agent, possibly microbial, or to some self-antigen

Major routes of HIV infection

1. *Sexual Transmission* • 75% of HIV transmission • The virus is present in semen, extracellularly and within mononuclear inflammatory cells, and it enters the recipient's body through lacerations or abrasions in mucosa. 2. *Parenteral Transmission* • intravenous drug abusers (the largest group), hemophiliacs receiving factor VIII or IX concentrates, random recipients of blood transfusion 2. *mother-to-infant Transmission*

RA typically presents as

1. *Symmetric arthritis, principally affecting the small joints* of the hands and feet, ankles, knees, wrists, elbows, and shoulders. • The thin, smooth synovial membrane is transformed into edematous, frond-tike (villous) projections, formed by proliferating synovial-lining calls admixed with inflammatory cells, granulation tissue, and fibrous connective tissue. • This classic appearance is called pannus • With progression of the disease, the articular cartilage subjacent to the pannus is eroded and, in time, virtually destroyed. • The subarticular bone may also be attacked and eroded. Eventually the pannus fills the joint space, and subsequent *fibrosis and calcification* may cause permanent *ankylosis* 2. *Rheumatoid subcutaneous nodules* • In 25% of patients • Appear along the extensor surface of the forearm or other areas subjected to Mechanical pressure • Rare sites include lungs, spleen, heart, aorta, other • *Clinically nodules are firm, nontender, oval or rounded masses as large as 2 cm in diameter*. • *Microscopically*, they are ciharacterized by a central focus of fibrinoid necrosis surrounded by a palisade of macrophages, which in turn is rimed by granulation tissue

IMMUNE DEFICIENCY DISEASES

1.* Primary (Congenital) Immune Deficiency* • caused by inherited (defects affecting immune system development • Caused by mutations in genes involved in lymphocyte maturation or function • Most primary immune deficiency diseases are genetically determined and affect either adaptive immunity (i.e., humoral or cellular) or innate host defense mechanisms, including complement proteins and cells such as phagocytes and NK cells. 2. *Secondary Immune Deficiency* • Much more common than the primary (inherited) disorders. May be encountered in patients with malnutrition, infection, cancer, renal disease & sarcoidosis , therapy-induced suppression of the bone marrow and of lymphocyte function. • A classical example of Secondary Immune Deficiency is *Acquired Immunodeficiency Syndrome (AIDS)* • AIDS is a retroviral disease caused by the human immunodeficiency virus (H l V) • lt is characterized by Depletion of CD4+T lymphocytes with profound immunosuppression leading to opportunistic infections, secondary neoplasms,and neurologic manifestations

C. Capsule or D. Flagella

Choose the best answer related to the statement Increases virulence 1000s fold A. Endospores B. Pili C. Capsule D. Flagella

A. Endospores

Choose the best answer related to the statement Protects bacteria from harsh environments A. Endospores B. Pili C. Capsule D. Flagella

C. Translation

Protein is formed by _____________ of a nucleotide sequence encoded on the mRNA molecule A. Transcription B. Replication C. Translation D. Transformation

E. All of the above

Epinephrine A. Causes bronchodilation B. Is effective even after anaphylactic symptoms commence C. Replaces smooth muscle D. Decreases vascular permeability E. All of the above

binding of anti-CD28 to T cells, which interferes with signal transduction needed for T-cell activation

A clinical trial investigating the efficacy of a humanized anti-CD28 monoclonal antibody in prolonging kidney allograft survival shows that patients treated with this biologic reagent have significantly fewer episodes of chronic rejection. The probable mechanisms responsible for this effect is best explained by the:

C. Binding of anti-CD28 to T cells, which interferes with signal transduction needed for T cell activation

A clinical trial investigating the efficacy of humanized anti-CD28 monoclonal antibody in prolonging kidney allograft survival shows that patients treated with this biological reagent have significantly fewer episodes of chronic rejection. The probable mechanism responsible for this effect is best explained by the: A. Binding of anti-CD28 to B cells, which blocks their interaction with B7.1 and B7.2 expressed on T cells B. Formation of circulating CD28-anti-CD28 immune complexes C. Binding of anti-CD28 to T cells, which interferes with signal transduction needed for T cell activation D. Binding of anti-CD28 to suppressor T cells, which then become activated E. Binding of anti-CD28 to B and T cells which interferes with signal transduction and activation of both populations

D. Antigenic drift

A person can get the flu more than one time mainly due to A. Original antigenic sin B. Short half life of anti-influenza virus antibodies C. Insufficient time for them to develop antibodies against the new variants D. Antigenic drift

C.

A young adult is part of the phase Ill clinical trial for hepatitis B vaccine. As part of the trial, her specific antibody titers are measured several days after each injection. Several hours after the third injection, she suffers from joint aches and swelling and a slight rash. On completion of the study, examination of her records shows high titers of antibody after the first dose with increasingly greater titers with each subsequent dose. Her adverse reaction is most likely due to which of the following? A. production of antibodies cross-reacting with synovial (joint) antigens and epidermal antigens. B. reaction to the vehicle (substance in which the viral antigen is suspended). C. Arthus-type hypersensitivity reaction. D. Anaphylaxis reaction.

C. PCR followed by sequencing

Hepatitis B virus infection is usually acute and self-limited, chronic hepatitis or fulminant hepatitis. However, a nonsense mutation in the Hep e antigen correlates with fulminant hepatitis. Which of the following techniques would be most appropriate to test this possibility in a clinical sample? A. DNA microarrays B. Ribotyping C. PCR followed by sequencing D. Southern blot

AIRE likely regulates genes expressed in this subset of tissues, but not genes in other tissues.

AIRE is a transcriptional regulator that promotes the expression of some 'tissue-specific' proteins in thymic stromal cells. This provides a means to induce central tolerance of developing T cells to these antigens. Patients with inactivating mutations in AIRE (a disease known as APECED) develop a range of symptoms, several of which involve autoimmune attack of exocrine glands. However, analysis of many patients with APECED reveals that some organs in the body are never attacked by autoimmune T cells in individuals with this syndrome, whereas other organs are commonly found to be destroyed in these patients. This targeted autoimmune response against a subset of tissues in APECED patients indicates:

AIRE likely regulates genes expressed in this subset of tissues, but not genes in other tissues.

AIRE is a transcriptional regulator that promotes the expression of some 'tissue-specific' proteins in thymic stromal cells. This provides a means to induce central tolerance of developing T cells to these antigens. Patients with inactivating mutations in AIRE (a disease known as APECED) develop a range of symptoms, several of which involve autoimmune attack of exocrine glands. However, analysis of many patients with APECED reveals that some organs in the body are never attacked by autoimmune T cells in individuals with this syndrome, whereas other organs are commonly found to be destroyed in these patients. This targeted autoimmune response against a subset of tissues in APECED patients indicates: A. Some tissues in the body cannot be targeted by autoimmune mechanisms B. AIRE likely regulates genes expressed in this subset of tissues, but not genes in other tissues. C. Central tolerance is more efficient in deleting T cells reactive to some tissues in the body than others. D. Central tolerance is only important for deleting auto-reactive T cells recognizing self-antigens expressed in exocrine glands. E. Exocrine glands express much higher levels of self-antigens than other tissues do

B. AIRE likely regulates genes expressed in this subset of tissues, but not genes in other tissues.

AIRE is a transcriptional regulator that promotes the expression of some tissue specific proteins in thymic stromal cells. This provides a means to induce central tolerance of developing T cells to these antigens. Patients with inactivating mutations in AIRE (a disease known as APECED) develop a range of symptoms, several of which involve autoimmune attack of exocrine glands. However, analysis of many patients with APECED reveals that some organs in the body are never attacked by autoimmune T cells in individuals with this syndrome, whereas other organs are commonly found to be destroyed in these patients. This targeted autoimmune response against a subset of tissues in APECED patients indicates A. Some tissues in the body cannot be targeted by autoimmune mechanisms B. AIRE likely regulates genes expressed in this subset of tissues, but not genes in other tissues. C. Central tolerance is more efficient in deleting T cells reactive to some tissues in the body than others D. Central tolerance is only important for deleting auto-reactive T cells recognizing self antigens expressed in exocrine glands E. Exocrine glands express much higher levels of self-antigens than other tissues do

C. A. True. Membrane attack complex (MAC) formed by complement proteins can cause lysis of cells, including bacteria, virus-infected, and tumor cells. B. True. C5a is an important chemoattractant that directs the movement of leukocytes to the site of inflammation. C. False. C3b does not activate basophils to facilitate vasodilation and increased vascular permeability. Instead, it is involved in opsonization, which facilitates phagocytosis by coating the surface of microbes. D. True. C5a can activate mast cells, leading to the release of histamine, which facilitates vasodilation and increased vascular permeability. E. True. C3b can facilitate phagocytic engulfment of microbes through receptors on neutrophils and macrophages.

Activated complement proteins initiate a variety of processes that result in significant outcomes. Which complement protein is improperly linked to its outcome? A. Membrane attack complex- lysis of cells (such as bacteria, virus-infected, and tumor cells). B. C5a- directing the movement of leukocytes. C. C3b- facilitating vasodilation and increased vascular permeability by activating basophils. D. C5a- facilitating vasodilation and increased vascular permeability by activating mast cells. E. C3b- facilitating phagocytic engulfment of microbes through neutrophils receptors.

D.

All of the following true about NK cell except.. A. Form 5-10 % of peripheral blood lymphocytes B. Cytotoxicity is not antibody dependent or MHC restricted C. They are CD16 and CD56 positive D. Ability of NK cell to kill target cell is directly proportional to target cell expression of MHC class II molecule

E. A. True. The three pathways for complement activation are the classical pathway, lectin pathway, and alternative pathway. Two of the three pathways (classical and lectin) are initiated by recognition molecules that directly interact with microbial surfaces. B. True. The complement cascade leads to the formation of a membrane-attack complex that can lyse cells, including bacteria and viruses. C. True. Several of the soluble products generated by complement activation, such as C5a and C3a, promote the inflammatory response. D. True. Complement proteins bound to the pathogen can promote uptake and destruction by phagocytic cells by opsonization and phagocytosis. E. False. The C3 convertase can be formed by the classical, lectin, or alternative pathway, and it can be activated by various recognition molecules, not only by antibodies.

All the following are true, EXCEPT: A. Two of the three pathways for complement activation are initiated by constitutively produced recognition molecules that directly interact with microbial surfaces. B. The complement cascade leads to the formation of a membrane-attack complex. C. Several of the soluble products generated by complement activation lead promote the inflammatory response. D. Complement proteins bound to the pathogen promote uptake and destruction by phagocytic cells. E. The C3 convertase is only produced when an antibody binding initiates complement activation to a pathogen.

B. A. True. The complement-binding site is located on the heavy chain of IgM. B. False. Both IgM and IgG are capable of activating the complement system when they bind to their specific antigens. C. True. The complement-binding site is located on the heavy chain of IgG. D. True. IgA has a limited capacity to fix the complement system compared to IgM and IgG. E. True. IgE has a very limited capacity to fix the complement system.

All the following are true, EXCEPT: A. the complement-binding site is on the heavy chain of IgM. B. Free circulating IgM and IgG do not activate complement. C. the complement-binding site is on the heavy chain of IgG. D. IgA has a relative capacity to fix the complement system. E. IgE has no relative capacity to fix the complement system. MacBook

E.

An antibody response to a protein vaccine can only be obtained: A If the molecule is first linked to a carrier B If the molecule maintains discontinuous epitopes C If the molecule is glycosylated D If disulfide bonds are maintained E If the peptide bonds are maintained

C.

An atopic person was exposed to an allergen and assume that he will be sensitized. He is subjected to a skin test after ten days. Predict the outcome if Fc fragments of human IgE I with a half life of 20 days] was injected at the same site immediately after antigen exposure but prior to the skin test. A. No reaction would occur because the Fc fragments would interact with the allergen and prevent it from gaining access to the sensitized mast cells. B. No reaction would occur because the Fc fragments would interact with the IgE antibodies making their antigen-binding sites unavailable for binding to antigen. C. No reaction would occur because the Fc fragments would interact with Fc receptors on mast cells. D. The reaction would be exacerbated due to the increased local concentration of IgE Fc fragments. E. The reaction would be exacerbated due to the activation of complement.

C. No reaction would occur because the Fc fragments would interact with Fc receptors on mast cells.

An atopic person was exposed to an allergen and assume that the will be sensitized. He is subjected to a skin test after ten days. Predict the outcome if Fc fragments of human IgE (with a half life of 20 days) was injected at the same site immediately after antigen exposure but prior to the skin test. A. No reaction would occur because of the Fc fragments would interact with the allergen and prevent it from gaining access to the sensitized mast cells. B. No reaction would occur because the Fc fragments would interact with the IgE antibodies C. No reaction would occur because the Fc fragments would interact with Fc receptors on mast cells. D. The reaction would be exacerbated due to the increased local concentration IgE Fc fragments E. The reaction would be exacerbated due to the activation of the complement

B. Trp operon

An example of a reprensible operon regulated by attenuation is A. Lac operon B. Trp operon C. Synthesis of ribosomal proteins D. Heat shock protein expression

B.

An individual with hypothyroidism and blocking antibodies specific for thyroid-stimulating hormone receptor has an autoimmune disease based on which type of immune reaction? a. type I b. type Il c. type Ill d. type IV

True

Anaerobic bacteria have unique cytochrome chains that are able to use a variety of inorganic molecules as terminal electrons acceptors True/False

B.

Anaphylaxis can be triggered by cross-linking of IgE receptors on: A Monocytes B Mast cells C B-cells D Eosinophils E T-cells

D. Tetracylines

Antibiotics function in five major ways. Which of the following interferes with protein synthesis? A. Sulfonamides B. Polymyxins C. Penicillins D. Tetracylines E. Quinolones

True

Antibodies to cell wall teichoic acid fail to opsonize encapsulated strains. True or False

E. Modifying antibiotic structure This prevents it from being able to bind

Beta-Lactamases confer antibiotic resistance by A. Altering antibiotic permeability B. Altering penicillin-binding proteins C. Altering 70s ribosome structure D. Modifying cellular RNA polymerase E. Modifying antibiotic structure

C. Negative selection of thymocytes Remember negative selection takes place in the thymus = central tolerance and activation of IL 2 gene is very important for T cell activation and proliferation

Blocking any of the following processes can result in peripheral tolerance in mature T cells except A. The interaction of co-stimulatory molecules on T cells with their ligands on APC B. Intracellular signal transduction mechanisms C. Negative selection of thymocytes D. Activation of the IL 2 gene

negative selection of thymocytes

Blocking any of the following processes can result in peripheral tolerance in mature T cells except:

Active transport: ATP-dependent

Indicate the transport system represented by letter E

C.

C3 convertase cleaves C3 in blood plasma, leading to a conformational change in the C3b fragment that exposes its reactive thioester group. The activated C3b is potentially harmful to the host if it becomes covalently attached to a host cell rather than to the surface of a pathogen. This deleterious outcome is primarily avoided by: A. The inability of active C3b to diffuse away in the blood plasma. B. The failure of active C3b to covalently attach to the membranes of eukaryotic cells. C.The rapid hydrolysis of active C3b in solution renders it inactive. D. The tight binding of active C3b to the C3 convertase. E.The ability of active C3b to recruit phagocytic cells.

A. Variable domains of anti-CD19 antibody

CAR T cell therapy is gaining popularity as a promising cancer treatment. In the picture, the depicted T cell has CAR receptor that is against CD-19 which is expressed on B cell leukemias as well as healthy B cells. The structure that is labeled A is A. Variable domains of anti-CD19 antibody B. CD3 C. CD8 D. CD19 E. Constant domains of anti-CD19 antibody

Variable domains of anti-CD19 antibody

CAR T cell therapy is gaining popularity as a promising cancer treatment. In this picture, the depicted T cell has CAR receptor that is against CD-19 which is expressed on B cell leukemias as well as healthy B cells. The structure that is labeled A is:

CD3(zeta)

CAR T cell therapy is gaining popularity as a promising cancer treatment. In this picture, the depicted T cell has CAR receptor that is against CD-19 which is expressed on B cell leukemias as well as healthy B cells. The structure that is labeled B is:

CD-19

CAR T cell therapy is gaining popularity as a promising cancer treatment. In this picture, the depicted T cell has CAR receptor that is against CD-19 which is expressed on B cell leukemias as well as healthy B cells. The structure that is labeled C is:

C.

CART cells have shown remarkable efficacy in treating hematological malignancies (e.g., leukemias). More recently, efforts have been underway to design CART cells to target solid tumors. One example currently in trials is a CART cell therapy for tumors expressing the protein mesothelin, a tumor-associated-antigen found in many pancreatic cancers, ovarian cancers, and some lung cancers. A design of a CAR to target mesothelin is shown in the figure. In this cartoon, the component of the CAR indicated by the arrow is composed of: A. T-cell receptor specific for mesothelin rumor cell B. The ligand that usually binds to mesothelin C. The Fab fragment of an anti-mesothelin antibody D. A co-stimulatory receptor signaling domain 4-1BB signaling domain CD3 & chain ITAMs E. The CD3 signaling components of the T-cell receptor

C. Is based on recognition and cleavage of exogenous DNA by a library of DNA sequences

CRISPR-CAS9 recombination A. Imparts specificity to the process of anti-viral antibody production B. Allows for chromosomal integration of non-homologous exogenous DNA C. Is based on recognition and cleavage of exogenous DNA by a library of DNA sequences D. Mechanism for integration of viral DNA in the host cell genome

A.

Complement proteins are synthesized in the liver and maintained as zymogens without infection due to their potential effector functions. Is this statement true or false? A.True B.False

C. Both

Complexed with polyamines A. Bacterial B. Eukaryotic C. Both

A. Cyclosporin A, but not rapamycin, blocks cytokine production by T cells

Cyclosporin A and rap Amy in are each used as T cell immunosuppressants. They share the property of binding to immunophilin molecules in T cells as the initial step in their mechanism of action. However, in the case of cyclosporin A, the drug immunophilin complex binds to and inhibits the protein phosphatase calcineurin, whereas the rapamycin:immunophilin complex binds to and inhibits mTOR. As a consequence, A. Cyclosporin A, but not rapamycin, blocks cytokine production by T cells B. Both Cyclosporin A and rapamycin block cytokine production by T cells C. Rapamycin, but not cyclosporin A, blocks T cell proliferation D. Both cyclosporin A and rapamycin inhibit co-stimulators signaling through CD28 on T cells

Cyclosporin A, but not rapamycin, blocks cytokine production by T cells

Cyclosporin A and rapamycin are each used as T cell immunosuppressants. They share the property of binding to immunophilin molecules in T cells as the initial step in their mechanisms of action. However, in the case of cyclsporin A, the drug:immunophilin complex binds to and inhibits the protein phosphatase calcineurin, whereas the rapamycin:immunoglobin complex binds to and inhibits mTOR. As a consequence,

B. Template, finished

DNA replication is semiconservative because the _______________ strand will become half of the ______________ molecule. A. RNA, DNA B. Template, finished C. Sense, mRNA D. Codon, Anticodon

B. Macrophages

Delayed type hypersensitivity is characterized by infiltration of A. Antibodies B. Macrophages C. Neutrophils D. Mast cells

C. Conjugation

During a co-culture experiment of two bacterial species, one that produces capsule and the other that does not, the lab tech observed that when bacterial samples where grown in agar, the bacteria that produced "rough" colonies now produced "smooth" ones. This effect was not seen if the co-culture was done with the two species grown separated by a <10 micron mesh. What process of DNA exchange is probably the one at play in this scenario? A. Transformation B. Transduction C. Conjugation D. Lysis E. Transfection

C. OmpF

During low osmolarity conditions, _______________ is preferentially expressed A. Sex pili B. OmpC C. OmpF D. TonB dependent proteins

B. The rho factor binds to the end of the RNA chain and slides along the strand towards the polymerase

During rho-dependent transcription termination A. The rho factor recognizes the Shine Dalgarno sequence on the RNA molecule B. The rho factor binds to the end of the RNA chain and slides along the strand towards the polymerase C. A hairpin loop forms that is recognized by the rho factor D. The rho factor employs energy to interchange sigma factors in the RNA polymerase

C. Transcription is allowed to proceed only when there are insufficient levels of amino acids

During transcription regulation via Attenuation A. A group of operons is controlled by a common regulator (e.g alternative sigma factors) B. Transcription has occurred but translation start is regulated C. Transcription is allowed to proceed only when there are insufficient levels of amino acids D. Adjacent, function-related genes are transcribed as a single mRNA molecule

Qur'an 13:11

Each person has angels before him and behind, watching over him by God's command

B.

For vaccination against mycobacterial diseases such as tuberculosis, what is the most important facet of the immune response to be stimulated? A A high titer of antibody B Macrophage-activating cell-mediated immunity C Cytotoxic T-cells D Antibody in the gut lumen E Neutrophils

B.

Glomerulonephritis associated with pulmonary hemorrhage is referred to as: A Pemphigus vulgaris B Goodpasture's syndrome C Systemic lupus erythematosus D Lambert-Eaton syndrome E Post-streptococcal glomerular nephritis

D. Monocytes and Neutrophils

GoodPasteur's syndrome is caused by auto reactive IgG against type IV collagen, found in basement membrane of renal glomeruli and tubules. In the image of renal corpuscle from a patient suffering from GoodPasteur's syndrome, Identify the cells that have infiltrated the space surrounding the glomerular capillaries causing damage. A. Lymphocytes B. Mast cells and Basophils C. Eosinophils D. Monocytes and Neutrophils

Monocytes and Neutrophils

Goodpasture's syndrome is caused by autoreactive IgG against type IV collagen, found in basement membrane of renal glomeruli and tubules. In the image of renal corpuscle from a patient suffering from Goodpasteur's syndrome, identify the cells that have infiltrated the space surrounding the glomerular capillaries.

D.

Great precautions must be exercised post transplantation. Some of the guidelines prohibits the cleaning of cat litter or coming in contact with it. This is mainly due to risks associated with A) EBV B) CMV C) Strongyloides fuelleborni D) Toxoplasma gondit

D. Using alternative RNA polymerase sigma factor

Heat shock response in bacteria is regulated by A. Phase variation B. Antisense RNA C. Competitive binding of repressor protein D. Using alternative RNA polymerase sigma factor

C. CD8+ T cells

Immune responses to tumors have been studied extensively in mice, using transplantable tumors injected into syngeneic mice. The basis for many of these studies is the assumption that the process of tumorigenesis generates mutations in genes encoding self-antigens that would allow the immune system to see these mutant proteins as foreign. In this scenario, the dominant immune response targeting the tumor cells would be mediated by: A. Antibodies B. CD4+ TH1 cells C. CD8+ T cells D. NK cells E. FcR+ phagocytic cells

D.

Immunotherapies promoting anti-tumor immune responses are being developed for tumors of many different tissue or cell-type origins. Interestingly, when tested in clinical trials, some of these approaches were also found to cause patients to develop autoimmune symptoms related to their tumor type. For instance, in patients with malignant skin cancer (melanoma), immunotherapy treatment can develop an autoimmune disorder known as vitiligo. T cells attack and destroy melanocytes in the skin, causing depigmentation. These findings indicate that in some individuals, the melanoma-specific anti-tumor T-cell responses are directed at: A. Tumor-specific mutated oncogenes B. Transcription factors not typically expressed in melanocytes C. Oncogenic proteins encoded by viruses D. Proteins commonly expressed in melanocytes E. Neoantigens created from the expression of abnormally spliced mRNAs

A.

Immunotoxin therapy as an anticancer treatment is a focus of current efforts to develop new anticancer drugs. An alternative strategy, radioimmunotherapy, involves conjugating a tumor-antigen-specific antibody to a radioisotope rather than a bacterial toxin. One advantage of radioimmunotherapy over that immunotoxin therapy is that the radioisotope: A. Will damage neighboring tumor cells in addition to the cell binding to the drug B. It has a finite half-life and will spontaneously lose activity in the patient C. Is less likely to cause collateral damage to healthy tissues than the toxin D. It will not cause inflammation due to recognition by PRRs in innate immune cells, but the toxin will E. It is unable to bind to Fc receptors on phagocytic cells, so it will have increased longevity in patients

Prospective recipient expresses the B27, A1 and A2 HLA specificities.

In a microcytotoxicity assay, the leukocytes from the recipient are killed by complement in the presence of anti-A1, Anti-A2, and anti-B27. This can lead to the conclusion that

B. Prospective recipient expresses the B27, A1, and A2 HLA specificities

In a microcytotoxicity assay, the leukocytes from the recipient are killed by complement in the presence of anti-A1, anti-A2, and anti-B27. This can lead to the conclusion that A. Prospective donor expresses the B27, A1 and A2 HLA specificities B. Prospective recipient expresses the B27, A1, and A2 HLA specificities C. Prospective recipient does not express the B27, A1, and A2 HLA specificities D. The prospective donor and recipient are not siblings E. The prospective recipient should not receive graft that expresses these HLA specificities

B. Colony; cell

In a viable plate count, each ____________ represents a _____________ from the sample population. A. Cell; colony B. Colony; cell C. Hour; generation D. Cell; generation

The up-regulation of MHC class I and class II molecules on activated dendritic cells

In some cases, a transient autoimmune process can occur as a result of an infection. This may be due to molecular mimicry between the pathogen and a self-antigen, or to the release of normally sequestered self-antigens due to tissue damage from the infection. An important factor leading to these autoreactive immune responses is the activation of dendritic cells by the infection-induced inflammation. Once the infection is resolved, this inflammation will also subside. As a consequence, autoreactive T cells mat not longer receive sufficient signals to promote their activation, causing a remission in the autoimmune symptoms. One important change in antigen-presenting dendritic cells during an infection that would contribute to the activation of normally self-tolerant self-reactive T cells is:

A. Catalase and SOD positive Remember aerobes require oxygen and cannot ferment

Indicate which combination (if any) would be used during oxygen metabolism as it relates to: Aerobes (Obligate) A. Catalase and SOD positive B. Catalase and SOD Negative C. Catalase and SOD +/-

A. Catalase and SOD positive Remember aerotolerant anaerobes Ferment regardless of oxygen present, if oxygen is present it wont use it? Most are negative for catalase and positive of SOD

Indicate which combination (if any) would be used during oxygen metabolism as it relates to: Aerotolerant Anaerobes A. Catalase and SOD positive B. Catalase and SOD Negative C. Catalase and SOD +/-

B. The up-regulation of MHC class I and class II molecules on activated dendritic cells

In some cases, a transient autoimmune process can occur as a result of an infection. This may be due to molecular mimicry between the pathogen and a self-antigen, or to the release of normally sequestered self-antigens due to tissue damage from the infection. An important factor leading to these autoreactive immune responses is the activation of dendritic cells by the infection-induced inflammation. Once the infection is resolved, this inflammation will also subside. As a consequence, autoreactive T cells mat not longer receive sufficient signals to promote their activation, causing a remission in the autoimmune symptoms. One important change in antigen-presenting dendritic cells during an infection that would contribute to the activation of normally self-tolerant self-reactive T cells is: A. The down-regulation of phagocytic activity by activated dendritic cells B. The up-regulation of MHC class I and class II molecules on activated dendritic cells C. The increased production of Type I interferons by activated dendritic cells D. The increased expression of cytoplasmic nucleic acid sensors by activated dendritic cells E. The down-regulation of anti-inflammatory cytokines, such as IL-10, by activated dendritic cells

B. The up-regulation of MHC class I and class II molecules on activated dendritic cells Remember clonally ignorant = self active

In some cases, a transient autoimmune process can occur as a result of an infection. This may be due to molecular mimicry between the pathogen and self-antigen, or to the release of normally sequestered self antigens due to tissue damage from the infection. An important factor leading to these auto reactive immune responses is the activation of dendritic cells by the infection-induced inflammation. Once the infection is resolved, this inflammation will also subside. As a consequence, auto reactive T cells may no longer receive sufficient signals to promote their activation, causing a remission in the autoimmune symptoms. One important change in antigen-presenting dendritic cells during an infection that would contribute to the activation of normally self-tolerant self reactive T cells is: A. The down-regulation of phagocytic activity by activated dendritic cells B. The up-regulation of MHC class I and class II molecules on activated dendritic cells C. The increased production of Type I interferons by activated dendritic cells D. The increased expression of cytoplasmic nucleic acid sensors by activated dendritic cells E. The down-regulation of anti-inflammatory cytokines, such as IL-10, by activated dendritic cells

B. Antigenic shift

In spring of 2009, an H1N1 virus with genes from North American wine, Eurasian swine, humans and birds emerged to infect people and quickly spread, causing a pandemic. This was mainly due to A. A phenomenon called original antigenic sin B. Antigenic shift C. Insufficient time for them to develop antibodies against the new variants D. Antigenic drift

DNA; Chromatin proteins; Ribonucleoprotein antigens [All of the above]

In systemic lupus erythematosus the autoantigen targeted by the immune system is not tissue-specific wherein the autoantibodies and autoreactive T cells are made against:

C. Temporarily deplete the patients T cells

In the first few days following organ transplantation, patients are often treated with several doses of an antibody mixture known as anti-thymocyte globulin. The anti-thymocyte globulin is generated by immunizing rabbits or horses with human T cells, to generate antibodies against the human T cell surface molecules. The immediate post-operative treatment with anti-thymocyte globulin is likely used to: A. Activate the patients T cells in vivo to prevent infections B. Enhanced the binding of the T cell receptor to peptide: MHC on the graft C. Temporarily deplete the patients T cells D. Allow the clinicians to monitor the patients T cell numbers by flow cytometry

Temporarily deplete the patient's T cells

In the first few days following organ transplantation, patients are often treated with several doses of an antibody mixture known as anti-thymocytes globulin. The anti-thymocyte globulin is generated by immunizing rabbits or horses with human T cells, to generate antibodies against the human T cell surface molecules. The immediate post-operative treatment with anti-thymocyte globulin is likely used to:

E.

In the progression to type 1 diabetes, data describing autoantibody isotypes are highly controversial. Previous reports have indicated that the predominant diabetes-associated autoantibody isotypes in type 1 diabetes are IgG1 and IgG3. Which of the following groups of patients would you not analyze for complement proteins? a. patients with recently diagnosed Type 1 diabetes. b. healthy first-degree relatives of this recent Type 1 onset group. c. patients with diabetes of more than 1-year duration without complications. d. patients with documented complications. e. Patients with a recent history of infection.

Group translocation

Indicate the transport system represented by letter A

Active transport: Proton gradient

Indicate the transport system represented by letter B

Diffusion

Indicate the transport system represented by letter C

Facilitated diffusion

Indicate the transport system represented by letter D

B.

Individuals with peanut allergies can exhibit a variety of symptoms following exposure to the peanut allergen. These symptoms can include a runny nose, skin reactions such as hives, itching in the mouth and throat, digestive problems such as cramps, diarrhea or vomiting, and shortness of breath or wheezing as a result of: A. Systemic production of inflammatory mediators causing responses in many tissues B. The presence of mast cells with pre-bound IgE in all mucosal tissues C. The simultaneous exposure of skin, oral mucosa, throat, and gastrointestinal tract to an ingested allergen D. The high concentrations of histamine present in pre-stored mast cell granules E. The presence of high concentrations of IgE in the circulation

B. The presence of mast cells with pre-bound IgE in all mucosal tissues

Individuals with peanut allergies can exhibit a variety of symptoms following exposure to the peanut allergen. These symptoms can induce a runny nose, skin reactions such as hives, itching in the mouth and throat, digestive problems such as cramps, diarrhea or vomiting, and shortness of breath or wheezing as a result of A. Systemic production of inflammatory mediators causing responses in many tissues B. The presence of mast cells with pre-bound IgE in all mucosal tissues C. The simultaneous exposure of skin, oral mucosa, throat, and gastrointestinal tract to an Ingested allergen. D. The high concentrations of histamine present in pre-stored mast cell granules E. The presence of high concentrations of IgE in the circulation

C. A substantial numbers of granulomas

Leprosy is a disease caused by the intracellular bacterium Mycobacterium Leprae, which infects macrophages and replicates in their phagosomes. Human patients with leprosy have a persistent infection of the mycobacteria, as their immune systems are unable to complete eradicate the pathogen. Furthermore, two different forms of the disease have been identified. Some patients have many skin lesions containing a large number of bacteria with little inflammatory response. This is the very disfiguring form of the disease, and is known as lepromatous leprosy. In other patients, few skin lesions and only occasional bacteria are observed, and the skin lesions are accompanied by a robust inflammatory response. These patients have the form of the disease known as tuberculoid leprosy. If one examined a skin biopsy from a patient with tuberculoid leprosy, one would expect to see: A. A large influx of neutrophils and other granulocytes B. A widespread occurrence of tissue necrosis C. A substantial numbers of granulomas D. Evidence of large numbers of dead or dying mycobacteria E. A large number of skin epithelial cells with intracellular bacteria

A. Lyse the phagocytic vesicle membrane, allowing bacterial escape into the cytoplasm

Listeria monocytogenes is a bacterial pathogen that causes a variety of diseases including gastroenteritis, encephalitis, and sepsis. The bacterium has evolved a strategy to replicate in the cytosol of macrophages, and to spread from one macrophage to another using the host's actin machinery to facilitate direct transfer between cells, thereby avoiding the extracellular space. This unique lifestyle of L monocytogenes is dependent on the bacteria encoding enzymes that: A. Lyse the phagocytic vesicle membrane, allowing bacterial escape into the cytoplasm B. Prevent bacterial membrane proteins from activating pattern recognition receptors expressed in the macrophage C. Block the MHC class II antigen presentation pathway D. Block the MHC class I antigen presentation pathway E. Induce the formation of granulomas that allow the bacteria to persist in definitely in the host

Breakdown of self tolerance

MHC (HLA) molecules do not distinguish between self & foreign peptide antigens

D.

Mannose-binding lectins (MBL) and ficolins are selective for activating complement on the surfaces of microbial pathogens rather than host cells because: A. Their higher-order oligomeric structure can be assembled only after the monomers bind to pathogen membranes. B. They only recruit MASP (MBL-associated serine proteases) proteins when bound to pathogen surfaces and not when attached to host cells. C. They only undergo the conformational change needed to activate MASP proteins when bound to a pathogen, not a host cell. D. They only bind to carbohydrate side chains and oligosaccharide modifications found on pathogen surfaces but not on host cell membranes. E. The activated MASP proteins are rapidly inactivated by hydrolysis when present on the surface of a host cell.

B. Transcription

Messenger RNA is formed by _____________ of a gene on the DNA template strand A. Transformation B. Transcription C. Replication D. Translation E Translocation

B. Complement activation leads to the generation of a cascade of proteases that cleave and activate downstream components of the complement pathway. The resulting amplification loop can lead to the rapid depletion of complement proteins in the serum, especially when complement activation occurs on a large scale. This can compromise the host's ability to fight infections, as complement plays a critical role in the opsonization and clearance of microbes. In some cases, genetic deficiencies in complement regulatory proteins can lead to uncontrolled complement activation, leading to the depletion of serum complement proteins and increased susceptibility to bacterial infections.

Multiple pathways for regulating complement activation limit the potential damage caused by complement deposition on host cells or caused by the spontaneous activation of complement proteins in the plasma. Genetic deficiencies in complement regulation often lead to chronic inflammatory diseases but, in some cases, can paradoxically lead to increased susceptibility to bacterial infections. This latter outcome may occur because: A. Complement regulatory proteins have dual functions in inhibiting and promoting complement activation. B. Uncontrolled complement activation leads to the depletion of serum complement proteins. C. The inhibition of the membrane attack complex by complement regulatory proteins typically leads to enhanced activation of the early steps of the complement pathway. D. Complement regulatory proteins commonly cause the rapid depletion of plasma complement factors. E. Uncontrolled complement activation recruits most phagocytic cells, leaving few remaining to fight tissue infections.

A.

Mycobacterium leprae, the causative agent of leprosy in humans, is an intracellular pathogen that resides in the phagosome of macrophages. Leprosy presents in two main clinical manifestations. Tuberculoid leprosy results in the formation of granulomas and a cell-mediated immune response, whereas lepromatous leprosy results in the production of high levels of IL4 and hypergammaglobulinemia. If Tm2 is produced in high levels during an M. leprae infection, which type of leprosy would result? A Lepromatous leprosy B Tuberculoid leprosy C. Either lepromatous leprosy or tuberculoid leprosy D. Neither; leprosy depends on the expression of TREG cells

C. Anaerobic respiration

Name the pathway Glucose (glycolysis) ——> Pyruvate ——-> CO2 + Nítrate/Nitrogen A. Embden Meyerhof B. Aerobic respiration C. Anaerobic respiration D. Fermentation E. Spilt TCA cycle

Pentose Phosphate Shunt

Name the pathway Glucose 6-P ————> 12 NADPH + Ribose 5-P

ED (Entner-Doudoroff) Pathway

Name the pathway Glucose ——> Pyruvate + Glyceraldehyde-3P ——> Pyruvate + 1 ATP

EMP (Embden-Meyerhof) Pathway (glycolysis)

Name the pathway Glucose ———-> 2 pyruvate + 2 ATP

D. Transplacental transfer of maternal IgG against the Ach receptor

Neonatal myasthenia gravis is though to be caused by A. Genetic defect B. Maternal T cells across the placenta C. Immune complexes in the kidneys D. Transplacental transfer of maternal IgG against the Ach receptor

Transplacental transfer of maternal IgG against the Ach receptor

Neonatal myasthenia gravis is thought to be caused by:

B. Antisense RNA

OmpC and OmpF are expressed differentially depending on osmolarity. In the presence of high osmolarity OmpF translation is repressed by A. Phase variation B. Antisense RNA C. Competitive binding of repressor protein D. Attenuation

D.

Patients with recurrent infections of Neisseria meningitidis were examined to determine the underlying cause of their immunodeficiency. These patients typically don't have defects in complement protein: A. C5-9 B. Factor D C. Factor P D. C1

D.

Physical effect of mast cell degranulation in eyes, nasal passages and airways lead to A. Increased peristalsis and fluid secretion B. Increased permeability and blood flow C. Vasoconstriction D. Decreased diameter, increased mucus secretion E. All of the above

D. Decreased diameter, increased mucus secretion

Physical effect of mast cell degranulation in eyes, nasal passages and airways lead to A. Increased peristalsis and fluid secretion B. Increased permeability and blood flow C. Vasoconstriction D. Decreased diameter, increased mucus secretion E. All of the above

D. Wiskott-Aldrich syndrome

Recurrent pyogenic infections, eczema, and low platelets characterize this syndrome. The symptoms typically appear during first year of life. It is an X linked disease caused by mutations in the WASp gene, leading to a defect in actin filament assembly that is important for T cells to respond to antigen presentation and for B cells to be activated by signals from the B cell receptor. These patients are therefore unable to mount an IgM responses to the capsular polysaccharides of bacteria, such as pneumococci, whereas IgA and IgE levels can be elevated. A. Selective IgA immunodeficiency B. X-Linked hypo-gamma-globulinemia C. DiGeorges syndrome D. Wiskott-Aldrich syndrome

B.

Red blood cells are common targets of drug-induced anemia, a disorder that occurs when some drugs bind to the surface of red blood cells and trigger the development of IgG antibodies. Since the drug binding to the red blood cell surface does not actually harm the red blood cell, the anemia resulting in this disorder is caused by: A. Trapping of red blood cells on large endothelial vessels B. Phagocytosis by Fcy-receptor expressing macrophages in the spleen C. Stimulation of CD4 T cells recognizing modified red blood cell surface proteins formed by the binding of the drug D. Stimulation of CD8 cytotoxic T cells that recognize drug-self protein conjugates and are triggered to kill the red blood cells

B. At least one proton pump is present in the ETC to create a transmembrane proton gradient

Regarding the bacterial ETC, which of the following statements is correct: A. Individual bacteria can only use one electron transport chain at a time B. At least one proton pump is present in the ETC to create a transmembrane proton gradient C. During aerobic growth, the terminal electron acceptor (O2) is reduced to water by a reductase D. Bacterial quinones such as ubiquinone menaquinone are proton pumps

A.

Sometimes DC cannot activate naïve T cells all by themselves. They need licensing from T helper cells in order to activate CD8 positive T cells. In this scenario, CD4 T cell help DC by A. Binding of CD40 receptor on DC B. Secreting IL-4 C. Binding to MHC I associated antigens on DC D. Becoming CD 8 T cells that require less stimulation

C.

Strep throat is commonly caused by group A Streptococcus bacteria. A common symptom of strep throat is the presence of swollen lymph nodes in the neck. This symptom usually peaks about 2-4 days after the onset of the infection, and is due to: A. Damage to the pharyngeal epithelium by the bacteria B. Release of bacterial PAMPs leading to inflammatory cytokine production C. Trapping and activation of antigen-specific lymphocytes in the lymph nodes of the neck D. Recruitment of neutrophils to the lymph nodes of the neck E. Recruitment of circulating macrophages to the lymph nodes of the neck

B. Leptin

Studies performed in mice have revealed one important component affecting the altered immune response in individuals undergoing malnutrition or starvation. In these studies, mice were placed on a starvation diet for several days, and then immunized with a protein antigen in an adjuvant. One group of starved mice were given injections of compound X for 48 hours, starting at the time of immunization. Seven days later, drawings lymph nodes were isolated, and T cell responses were measured in vitro following stimulation with antigen. The results are shown in the figure below. Compound X is most likely: A. IL-1beta B. Leptin C. TNF-Alpha D. IL-10 E. Double-stranded RNA

E. Both B and C

Tryptophan operon is regulated by A. Tryptophan binding to repressor when it is in high levels and inactivating it B. Attenuation C. Tryptophan binding to repressor when it is in high levels and activating it D. Terminating transcription when tryptophan levels are low E. Both B and C

B.

The Arthus reaction is characterized by an intense infiltration by: A Mast cells B Neutrophils C Eosinophils D Macrophages E Langerhans cells

B. RecA

The SOS system, a set of 30 genes coding for DNA repair enzymes, is activated when the cell suffers damage. The factor in charge of detecting the DNA damage and destroying the repressor is A. LexA B. RecA C. UmuC D. LacR E. Cro

D. Glyoxylate cycle

The TCA cycle provides many key biosynthetic intermediates such as amino acids and porphyrins. Bacteria uses this pathway to synthesize TCA intermediates that are depleted. A. Electron transport/Oxidative phosphorylation B. Pentose phosphate shunt C. Entner-Doudoroff pathway D. Glyoxylate cycle

Unvaccinated individuals are protected when 80% of people around them are vaccinated.

The US Department of Health and Human Services has a stated goal for the seasonal influenza vaccine of vaccinating 80% of healthy (i.e., low-risk) individuals. This vaccine is formulated each year from the serotypes of influenza likely to be circulating in the population during the coming flu season. The reason this goal is not 100% of individuals is because:

D. Unvaccinated individuals are protected when 80% of people around them are vaccinated.

The US department of health and human services has a stated goal for the seasonal influenza vaccine of vaccinating 80% of healthy (I.e. low risk) individuals. This vaccine is formulated each year from the serotypes of influenza likely to be circulating in the population during the coming flue season. The reason this goal is not 100% of individuals is because: A. Individuals who has the flue vaccine the year before will already be protected B. Individuals who are healthy need not be too concerned about getting infected with the flue C. Healthy individuals are unlikely to spread the virus to others D. Unvaccinated individuals are protected when 80% of people around them are vaccinated.

False Cytokines bring about the release

The acute phase response contributes to infection control by producing molecules that promotes pathogen op sónica tion and complement activation. This response is only induced by direct action of microbial components on hepatocytes in the liver. True/False

False Cytokines bring about the release

The acute phase response contributes to infection control by producing molecules that promotes pathogen opsóniztion and complement activation. This response is only induced by direct action of microbial components on hepatocytes in the liver. True/False

True

The bacterial capsule blocks phagocytosis by interfering with binding of complement C3b to the cell surface. True or False

False, it targets antibodies

The capsule primarily activates T-cell mediated immunity. True or False

C.

The cell surface proteins on T cell bind to B7 on the antigen-presenting cells and serve as a secondary signal. Which of the following statement is true regarding the secondary signal? A. CD28 is a protein that binds to B7 on APC that acts as costimulatory signals for T cell activation B. CTLA-4 is a protein that binds to B7 on APC that acts as a suppressor signal for T cell activation C. Both D. None

A.

The classical and alternative pathways of complement activation converge at the step of C3 activation. However, the initiating steps of each pathway use protein components and enzymatic mechanisms that share no similarity. A. True B. False

D. r determinants

The following carries genes for replication and antiboitic resistance, but not for transfer A. Fertility factors B. Resistance factors C. F' factors D. r determinants E. RTF factors

A. Enhanced production of IgG, which binds allergen before it reaches mast cells

The following mechanism(s) may be involved in the clinical efficacy of desensitization therapy to treat patients with allergies to known allergens: A. Enhanced production of IgG, which binds allergen before it reaches mast cells B. Skewing of T cell responses from TH2 to Tc C. Increased sensitivity of mast cells and basophils to degranulation of allergen D. Activation of complement proteins

B.

The following types of hypersensitivity reactions activate the complement system: A. Type 1 & 2 B. Type 2 & 3 C. Type 3 & 4 D. Type 2 & 4 E. Type 1, 2, 3, and 4

C. The levels of cAMP in the media

The genes that code for proteins involved in catabolite repression are regulated by? A. Covalent modifications B. Proteins that detect a signal C. The levels of cAMP in the media D. Are always on since they have a housekeeping function

False

The immune response is a dynamic process that initiates with an antigen-independent response, which becomes more focused and powerful as it develops antigen specificity. Once the adaptive immune system develops, a single type of response is capable of eliminating any type of antigen. True/False

A.

The importance of complement activation as an innate immune defense against infections is illustrated by the following: A. The evolution of complement avoidance strategies by many pathogens B. The large number of proteins involved in the complement pathway C. A large number of complement regulatory pathways expressed by the host D. The existence of three different mechanisms for initiating complement activation E. The ability of the membrane attack complex to lyse some pathogens

B. Off, inducer

The lac operon is usually in the _______________ position and is activated by a(n) ______________ molecule A. On, repressor B. Off, inducer C. On, inducer D. Off, repressor

A. Complementary; 5' to 3' Remember mRNA goes in the same direction as the coding (non template) strand

The mRNA molecule is ________________ to the template strand of the gene's DNA sequence, which means that mRNA is _______________ if coding strand is 5' to 3' A. Complementary 5' to 3' B. Complementary 3' to 5' C. Identical, 5' to 3' D Identical, 3' to 5'

C. Homology and thus potential for recombination into the host genome is assured during the DNA uptake process in some gram negative species

The mechanism of competence of Gram Negative bacteria is characterized by: A. Homologous or heterologous, double-stranded DNA enters the cell B. Transformasome complex needs to assembled through the thick peptidoglycan layer C. Homology and thus potential for recombination into the host genome is assured during the DNA uptake process in some gram negative species D. RecA recognizes methylation patterns to determine outcome of the exogenous DNA

False, its produced by exotoxin?

The polysaccharide in the capsule causes toxic shock syndrome. True or False

B. Consists of a hairpin loop region on the DNA template strand

The rho-independent signal A. Is based on enrichment of A-T pairings in the region B. Consists of a hairpin loop region on the DNA template strand C. Is recognized by terminator t-RNAs D. Is also known as TATA box

D.

The surface molecule on APC interacts with ------------ on the T cell to provide the necessary co-stimulation required for Th cell activation. A. CD80/86 or B7 B. CD40 C. MHC I or lI D. CD28 on the T

A. Transformation

The term used for acquisition of naked DNA from its environment and its incorporation in their genome by a bacterium is A. Transformation B. Lysogenic conversion C. Conjugation D. Transduction E. Transfection

B. Site-specific recombination

The type of recombination that commonly occurs between a pair of bacteriophage DNA and the bacterial chromosome is called A. Mutagenic recombination B. Site-specific recombination C. Replicative recombination D. General recombination

B. a5

There are 70 papilloma virus subtypes, however not all are associated with cervical, anal, and oral cancer, and no useful conventional method for diagnosis. Dot blotting is being used to correlate viral subtype and cancer risk. The following figure shows a nylon membrane showing a dot blot with a probe for HPV type 11, a low risk virus, in cervical samples. Which of the following patients appears to be at low risk for cervical cancer? A. b4 B. a5 C. a11 D. c10 E. b10

C.

To generate a vaccine to pertussis toxin, a heat-killed preparation of Bordetella pertussis (the bacteria that produce pertussis toxin) is mixed with a purified preparation of the inactivated toxin protein. The mixture is then injected subcutaneously into mice. In an effort to enhance the antibody response to the toxin, a group of test mice is depleted of all their dendritic cells immediately prior to immunization. However, instead of enhancing the antibody response, the dendritic cell depletion nearly eliminated the anti-toxin antibody response because: A. All of the toxin-specific B cells underwent apoptosis in the absence of dendritic cells. B. The heat-killed Bordetella pertussis could not be ingested by macrophages in the mice. C. Dendritic cells are needed to activate naive CD4 T cells, which can then help the B cells produce anti-toxin antibody. D. The macrophages in the mice did not express the appropriate pattern recognition receptors to recognize Bordetella pertussis

D. All of the answers are correct

Tolerance is promoted by A. Induction of anergy B. Induction of apoptosis C. Regulation of activity of cells D. All of the answers are correct E. None of the answers are correct

induction of anergy; induction of apoptosis; regulation of activity of cells [All of the answers are correct.]

Tolerance is promoted by:

False

True or False Endospores are a reproductive mechanism

True

True or False Endospores are induced by a combination of high temperature and high pressure

True

True or False Endospores are made of calcium dipicolinate, peptidoglycan or keratin

True

True or False Endospores have a highly regulated expression that involves controlled expression RNA polymerase sigma factors

False

True or False Most bacterial species produce endospores

True

True or False, Regarding flagella motility, bacteria usually move randomly

True

True or False, Regarding flagella motility, cocci rarely have flagella

True

True or False, Regarding flagella motility, flagella stains can be used for identification of bacteria

True

True or False. Regarding flagella motility, clockwise flagellar rotation results in tumbling

True

True or False. Regarding flagella motility, counter clockwise flagelar rotation equals swimming

Allergic and atopic disorders (rhinitis, hay fever, eczema, hives, asthma)

Type 1

Anaphylaxis (bee sting, food/drug allergy)

Type 1

Acute hemolytic transfusion rxns

Type 2

Bullous pemphigoid

Type 2

Erythroblastosis fetalis

Type 2

Goodpasture's syndrome

Type 2

Grave's disesae

Type 2

Hemolytic anemia

Type 2

ITP

Type 2

MG

Type 2

Pemphigus vulgaris

Type 2

Pernicious anemia

Type 2

Rheumatic fever

Type 2

Arthus reaction (swelling and inflammation following tetanus vaccine)

Type 3

Hypersensitivity pneumonitis

Type 3

Polyarteritis nodosum

Type 3

Poststreptococcal glomerulonephritis

Type 3

Rheumatoid arthritis

Type 3

SLE

Type 3

Serum Sickness

Type 3

Contact dermatitis

Type 4

Graft v host disease

Type 4

Guillain Barre

Type 4

Hashimoto's thyroiditis

Type 4

MS

Type 4

PPD

Type 4

Type 1 DM

Type 4

Allergic and atopic disorders (i.e. rhinitis, hay fever, eczema, hives, asthma).

Type I

Anaphylaxis (i.e. bee sting, etc.)

Type I

D.

Type I hypersensitivity can be blocked using: A. Histamine B. An anti-IgA monoclonal antibody C. A monoclonal of mixed antibody class D. Sodium cromoglycate (cromolyn sodium ) E. IL -5

Acute hemolytic transfusion reactions

Type II

Autoimmune hemolytic anemia

Type II

Bullous pemphigoid

Type II

Erythroblastosis fetalis

Type II

Goodpasture syndrome

Type II

Idiopathic thrombocytopenic purpura

Type II

Pemphigus vulgaris

Type II

Pernicious anemia

Type II

Rheumatic fever

Type II

Arthus reaction

Type III

Polyarteritis nodosa

Type III

Post-strep glomerulonephritis

Type III

SLE

Type III

Serum sickness

Type III

B. Antigen- antibody (IgG) complexes Because the antigens are free for answer choice D the surface antigens are bound (Type II)

Type III hypersensitivity reactions are induced by A. IgE antibodies B. Antigen- antibody (IgG) complexes C. T cells D. IgG/IgM antibodies against cell surface antigens

Contact dermatitis

Type IV

Graft-VS-Host disease

Type IV

Guillain-Barre syndrome

Type IV

Multiple sclerosis

Type IV

PPD (test for TB)

Type IV

C. Increased production of TNF-alpha AND IL-6 Remember these cytokines are produced by activated macrophages 26 degrees = strong response 37 degrees = less response

Yersinia pestis the causative agent of the bubonic plague, has multiple mechanisms of immune invasion. This gram negative bacterium is transmitted from fleas (body temperature, 26 C) to humans (body temperature, 37 C) by flea bites. Studies have shown that the lipopolysaccharide (LPS) produced by Y pestis grown at 37 C is about 10-fold less potent at stimulating TLR4 signaling than is the Y pestis LPS from bacteria grown at 26 C. When these two forms of Y pestis lPS are compared for their abilities to induce responses from human macrophages, one would expect that the 26 C Y pestis LPS would result in A. Increased production of antimicrobiano peptides B. Reduced production of IL-10 C. Increased production of TNF-alpha AND IL-6 D. Reduced production of Type I interferons E. Increased activation of the inflammasome

C. Increased production of TNF-alpha AND IL-6 Remember these cytokines are produced by activated macrophages 26 degrees = strong response 37 degrees = less response

Yersinia pestis the causative agent of the bubonic plague, has multiple mechanisms of immune invasion. This gram negative bacterium is transmitted from fleas (body temperature, 26 C) to humans (body temperature, 37 C) by flea bites. Studies have shown that the lipopolysaccharide (LPS) produced by Y pestis grown at 37 C is about 10-fold less potent at stimulating TLR4 signaling than is the Y. pestis LPS from bacteria grown at 26 C. When these two forms of Y pestis lPS are compared for their abilities to induce responses from human macrophages, one would expect that the 26 C Y pestis LPS would result in A. Increased production of antimicrobiano peptides B. Reduced production of IL-10 C. Increased production of TNF-alpha AND IL-6 D. Reduced production of Type I interferons E. Increased activation of the inflammasome

D. Lane 7

You are asked to determine if the bacteria growing in a clinical sample has a mutation that confers antibiotic resistance. You use PCR followed by incubation with HphI to assess the presence or absence of the mutant. Which lane(s) depicts the results from the mutant genotype? A. Lane 1 B. Lane 2,3 C. Lane 4-6, 8 D. Lane 7 HbA = wildtype HbE = mutant H = HphI

C. ELISA

You are asked to diagnose a 5 year old patient who presents to the ER in critical condition with symptoms of bacterial meningitis. You know that time is of the essence, so you request the following test of the spinal fluid that is going to be obtained and sent to the reference lab: A. Southern blot B. In situ hybridization C. ELISA D. RFLP-PFGE E. Ribotyping

You can do it!

You got this!

Graves disease

______ is much more common in women than in men (8:1), and its onset is usually between the ages of 20 and 40 years. It may be accompanied by infiltrative ophthalmopathy and, less commonly, by infiltrative dermopathy. The thymus gland is typically enlarged and serum antinuclear antibody levels are usually elevated. The TSH receptor is the target of stimulating antibodies. Histocompatibility studies have shown as association with group HLA-B8 and HLA-DR3.

E. LAD

_________________ consist of three autosomal recessive conditions. The most frequent condition is caused by mutations in the Beta 2 integrin gene (CD18); following leukocyte activation, beta 2 integrins mediate adhesion to inflamed endothelium expressing cognate ligands. Given that neutrophils are not able to reach infected tissues, the disease renders the individual susceptible to bacterial and fungal infections. A. DiGeorges Syndrome B. SCID C. Selective IgA D. XLA E. LAD

D. Reticular dysgenesis

__________________ is an extremely rare and the most severe form of SCID that causes T and NK deficiencies with severe neutropenia and sensorineural deafness. It results from defects in mitochondrial metabolism especially due to an adenylate kinase 2 deficiency. Curative treatment relies on hematopoietic stem cell transplant (HSCT) A. Selective IgA immunodeficiency B. X linked hypo gamma globulinemia C. DiGeorges syndrome D. Reticular dysgenesis

B. Graves Disease

____________________ is much more common in women than men (8:1), and its onset is usually between the ages of 20 and 40 years. It may be accompanied by infiltrative ophthalmopathy and, less commonly, by infiltrative dermopathy. The thymus gland is typically enlarged and serum antinuclear antibody levels are usually elevated. The TSH receptor is the target of stimulating antibodies. Histo compatibility studies have shown an association with group HLA-B8 and HLA-DR3. A. Hashimotos thyroiditis B. Graves Disease C. Pemphigus vulgaris D. Plummer's disease

When a nurse cares for a patient with systemic lupus erythematosus (SLE), the nurse remembers this disease is an example of: a. Autoimmunity b. Alloimmunity c. Homoimmunity d. Alleimmunity

a. Autoimmunity

A 22-year-old was recently diagnosed with acquired immunodeficiency syndrome (AIDS). Which decreased lab finding would be expected to accompany this virus? a. CD4 T-helper b. CD8 T-helper c. CDC cells d. CDC10 cells

a. CD4 T-helper

The mRNA molecule is ______ to the template strand of the gene's DNA sequence, which means that mRNA is _____ if coding strand it 5' to 3' a. Complementary, 5' to 3' b. Complementary, 3' to 5' c. Identical, 5' to 3' d. Identical, 3' to 5'

a. Complementary, 5' to 3'

What is the function of the Shine-Dalgarno sequence a. Directs ribosome to start codon b. Indicates the end of the protein synthesis process c. Recognizes the rho-dependent protein d. Is recognized by transcription factors

a. Directs ribosome to start codon

The following mechanism(s) may be involved in the clinical efficacy of desensitization therapy to treat patients with allergies to known allergens: a. Enhanced production of IgG, which binds allergen before it reaches mast cells b. Skewing of T cell responses from Th2 to Tc c. Increased sensitivity of mast cells and basophils to degranulation by allergen d. Activation of complement proteins

a. Enhanced production of IgG, which binds allergen before it reaches mast cells

Once an individual becomes sensitized to an allergen, such as an inhaled antigen, the allergic response can be self-amplifying upon each re-exposure to the allergen. Thus, even in the absence of CD4 TH2 cell activation, increases in IgE secretion by mucosal-resident plasma cell can be induced by: a. IL-4 secretion and CD40-ligand expression by mast cells and basophils b. Inflammatory macrophages recruited to the site of allergen stimulation c. Eosinophils that are stimulated by the production of IL-4 in the mucosal tissue d. Dendritic cells that have received TLR stimulation e. The activation of the complement cascade following allergen encounter

a. IL-4 secretion and CD40-ligand expression by mast cells and basophils

While planning care, a nurse recalls seasonal allergic rhinitis is expressed through: a. IgE-mediated reactions b. Tissue-specific reactions c. Antigen-antibody complexes d. Type II hypersensitivity reactions

a. IgE-mediated reactions

A bacteria utilizes available glucose in the medium and now is transferred to a new medium containing galactose. Which phase corresponds to this transition process? a. Lag phase b. Log phase c. Stationary phase d. Death phase

a. Lag phase

Listeria monocytogenes is a bacterial pathogen that causes a variety of diseases including gastroenteritis, encephalitis, and sepsis. The bacterium has evolved a strategy to replicate in the cytosol of macrophages, and to spread from one macrophage to another using the host's actin machinery to facilitate direct transfer between cells, thereby avoiding the extracellular space. This unique lifestyle of L. monocytogenes is dependent on the bacteria encoding enzymes that: a. Lyse the phagocytic vesicle membrane, allowing bacterial escape into the cytoplasm b. Prevent bacterial membrane proteins from activating pattern recognition receptors expressed in the macrophage c. Block the MHC class II antigen presentation pathway d. Block the MHC class I antigen presentation pathway e. Induce the formation of granulomas that allow the bacteria to persist indefinitely in the host

a. Lyse the phagocytic vesicle membrane, allowing bacterial escape into the cytoplasm

Which of the following does not exist in nature? a. Teichoic acid-rich outer membrane b. Waxes in the cell wall c. A polypeptide capsule d. Wall-less bacteria e. Bacteria resistant to boiling temperatures

a. Teichoic acid-rich outer membrane

Structure that induces competence, resistance to lysis and binds to CD14/TLR2 of macrophages is _____. a. Teichoic acids b. Lipopolysaccharide c. Lipid A d. Periplasmic space e. Porins

a. Teichoic acids

The term used for acquisition of naked DNA from its environment and it incorporation into the genome by bacterium is: a. Transformation b. Lysogenic conversion c. Conjugation d. Transduction e. Transfection

a. Transformation

Regarding the bacterial ETC, which of the following statements is correct: a. Individual bacteria can only use one electron transport chain at a time b. At least one proton pump is present in the ETC to create a transmembrane proton gradient c. During aerobic growth, the terminal electron acceptor (O2) is reduced to water by a reductase d. Bacterial quinones such as ubiquinone menaquinone are proton pumps

b. At least one proton pump is present in the ETC to create a transmembrane proton gradient

A 10-year-old male presents to his primary care provider reporting wheezing and difficulty breathing. History reveals that both of the child's parents suffer from allergies. Which of the following terms would be used to classify the child? a. Desensitized b. Atopic c. Hyperactive d. Autoimmune

b. Atopic

Which information indicates a correct understanding of viral vaccines? Most viral vaccines contain: a. Active viruses b. Attenuated viruses c. Killed viruses d. Viral toxins

b. Attenuated viruses

In a viable plate count, each ____ represents a ___ from the sample population a. Cell, colony b. Colony, cell c. Hour, generation d. Cell, generation

b. Colony, cell

The rho independent signal: a. Is based on enrichment of A-T pairings in the region b. Consists of a hair-pin loop region on the DNA template strand c. Is recognized by terminator tRNAs d. Is also known as TATAA box

b. Consists of a hair-pin loop region on the DNA template strand

When histamine is released in the body, which of the following responses would the nurse expect? a. Bronchial dilation b. Edema c. Vasoconstriction d. Constipation

b. Edema

A 5-year-old male becomes ill with a severe cough. Histologic examination reveals a bacterial infection, and further laboratory testing reveals cell membrane damage and decreased protein synthesis. Which of the following is the most likely cause of this illness? a. Endotoxin b. Exotoxin c. Hemolysis d. Septicemia

b. Exotoxin

Hypersensitivity responses to divalent cations such as nickel are relatively common. Individuals sensitized to these metals will develop a skin rash within 15 minutes of putting on a bracelet or ring containing that metal a. True b. False

b. False

Only TH2 cells can initiate the chain of signals needed to induce B cells to class-switch to IgE a. True b. False

b. False

The acute phase response contributes to infection control by producing molecules that promote pathogen opsonization and complement activation. This response is only induced by direct action of microbial components on hepatocytes in the liver. a. True b. False

b. False

Lactose binds to and inactivates the LacI repressor (lactose is a _____) a. Activator b. Inducer c. Repressor d. Operator e. Blocker

b. Inducer

A cell exposed to a hypertonic environment will _____ by osmosis. a. Gain water b. Lose water c. Neither gain nor lose water d. Burst

b. Lose water

Delayed type hypersensitivity is characterized by infiltration of: a. Ab b. Macrophages c. Neutrophils d. Mast cells

b. Macrophages

The lac operon is usually in the ____ position and is activated by a(n) _____ molecule. a. On, repressor b. Off, inducer c. On, inducer d. Off, repressor

b. Off, inducer

RBCs are common targets for drug-induced anemia, a disorder that occurs when some drugs bind the surface of RBCs and trigger the development of IgG antibodies. Since the drug binding to the RBC surface does not actually harm the RBC, the anemia resulting in this disorder is caused by: a. Trapping of RBCs on large endothelial cells b. Phagocytosis by FcƔ receptor expressing macrophages in the spleen c. Stimulation of CD4 T cells recognizing modified RBC cell surface proteins formed by the binding of the drug d. Stimulation of Cd8 cytotoxic T cells that recognize drug-self protein conjugates and are triggered to kill the RBCs

b. Phagocytosis by FcƔ receptor expressing macrophages in the spleen

The SOS system, a set of 30 genes coding for DNA repair enzymes, is activated when the cell suffers damage. The factor in charge of detecting DNA damage and destroying the repressor ia a. LexA b. RecA c. UmuC d. LacR e. Cro

b. RecA

H. pylori is a human GI pathogen that can lead to a state of chronic GI inflammation in some individuals, and has been linked to gastric ulcers and other diseases. Studies have shown that human mucosal gastric biopsies of infected individuals have DCs producing IL-23 in response to stimulation with live H. pylori. Given these findings, which of the following responses would be enhanced in the GI tract of H. pylori - infected individuals compared to unaffected individuals a. Mucus production by goblet cells b. Recruitment of neutrophils c. Recruitment of eosinophils d. Production of IL-13

b. Recruitment of neutrophils

What common symptom should be assessed in individuals with immunodeficiency? a. Anemia b. Recurrent infections c. Hypersensitivity d. Autoantibody production

b. Recurrent infections

In addition to matching ABO antigens, a blood transfusion must also be matched for: a. HLA type b. Rh antigen c. Immunoglobulins d. Platelet compatibility

b. Rh antigen

The type of recombination that commonly occurs between a pair of bacteriophage DNA and the bacterial chromosome is called: a. Mutagenic recombination b. Site-specific recombination c. Replicative recombination d. General recombination

b. Site-specific recombination

Which of the following effects is NOT a result of histamine binding to histamine receptor H1? a. Intestinal smooth muscle contraction b. Suppression of mast-cell degranulation c. Increased vascular permeability d. Increased mucous secretion e. All of the answers result from histamine binding H1

b. Suppression of mast-cell degranulation

When a nurse notices that a patient has type O blood, the nurse realizes that anti-_____ antibodies are present in the patient's body. a. A only b. B only c. A and B d. O

c. A and B

Leprosy is a disease caused by the intracellular bacterium mycobacterium leprae, which infects macrophages and replicates their phagosomes. Human pts with leprosy have a persistent infection of the mycobacteria, as their immune systems are unable to completely eradicate the pathogen. Furthermore, two different forms of the disease have been identified. Some pts have many skin lesions containing a large number of bacteria with little inflammatory response. This is the very disfiguring form of the disease, and is known as observed, and the skin lesions are accompanied by a robust inflammatory response. These patients have the form of the disease known as tuberculoid leprosy. If one examined a skin biopsy from a patient with tuberculoid leprosy, one would expect to see: a. A large influx of neutrophils and other granulocytes b. A widespread occurrence of tissue necrosis c. A substantial number of granulomas d. Evidence of large numbers of dead or dying mycobacteria e. A large number of skin epithelial cells with intracellular bacteria

c. A substantial number of granulomas

Secondary responses involving memory B cells are more robust compared to primary response and the antibodies generated have more affinity to the antigen because of a. Junctional diversity introduced by P and N nucleotides b. RAG1 and RAG2 genes c. Affinity maturation in the germinal center d. Class switching

c. Affinity maturation in the germinal center

When the maternal immune system becomes sensitized against antigens expressed by the fetus, what type of immune reaction occurs? a. Autoimmune b. Anaphylaxis c. Alloimmune d. Allergic

c. Alloimmune

When a patient asks the nurse what hypersensitivity is, how should the nurse respond? Hypersensitivity is best defined as: a. A reduced immune response found in most pathologic states b. A normal immune response to an infectious agent c. An excessive or inappropriate response of the immune system to a sensitizing antigen d. Antigenic desensitization

c. An excessive or inappropriate response of the immune system to a sensitizing antigen

A 10-year-old male is stung by a bee while playing in the yard. He begins itching and develops pain, swelling, redness, and respiratory difficulties. He is suffering from: a. Immunodeficiency b. Autoimmunity c. Anaphylaxis d. Tissue-specific hypersensitivity

c. Anaphylaxis

When a patient presents at the emergency department for an allergic reaction, the nurse recognizes the most severe consequence of a type I hypersensitivity reaction is: a. Urticaria b. Hives c. Anaphylaxis d. Antibody-dependent cell-mediated cytotoxicity (ADCC)

c. Anaphylaxis

What is the chance that two siblings share both HLA haplotypes, making them a good match for an organ transplant from one to the other? a. 100% b. 75% c. 50% d. 25%

d. 25%

A 15-year-old male suffers from severe hemorrhage following a motor vehicle accident. He is given a blood transfusion, but shortly afterward the red blood cells are destroyed by agglutination and lysis. Which of the following blood type-transfusion type matches would cause this? a. A-A b. B-O c. AB-O d. A-AB

d. A-AB

A person can get the flu more than one time mainly due to: a. Original antigenic sin b. Short half life of anti-influenza virus Ab c. Insufficient time for them to develop Ab against the new variants d. Antigenic drift

d. Antigenic drift

After studying about fungi, which information indicates a correct understanding of fungi? Fungi causing deep or systemic infections: a. Are easily treated with penicillin b. Are extremely rare c. Never occur with other infections d. Are commonly opportunistic

d. Are commonly opportunistic

A 30-year-old male is having difficulty breathing and has been spitting blood. He reports that he began experiencing this reaction after cleaning his pigeons' cages. Testing reveals he is suffering from allergic alveolitis. Which of the following is he experiencing? a. Serum sickness b. Raynaud phenomenon c. Antibody-dependent cytotoxicity d. Arthus reaction

d. Arthus reaction

A 5-year-old female takes a hike through the woods during a school field trip. Upon returning home, she hugs her father, and he later develops poison ivy. Which of the following immune reactions is he experiencing? a. IgE-mediated b. Tissue specific c. Immune complex d. Cell-mediated

d. Cell-mediated

Which of the following techniques is more appropriate for simultaneous detection of RNA from influenza virus A/H1N1, A/H3N2, A/H5N1 and influenza B virus from the same clinical sample? a. Western blot b. Ribotyping c. RFLP-PFGE d. DNA microarrays e. ELISA

d. DNA microarrays

The nurse would correctly respond that the etiology of a congenital immune deficiency is due to a(n): a. Negative response to an immunization b. Adverse response to a medication c. Renal failure d. Genetic defect

d. Genetic defect

The TCA cycle provides many key biosynthetic intermediates such as amino acids and porphyrins.bacteria use this pathway to synthesize TCA intermediates that are depleted a. Electron transport/oxidative phosphorylation b. Pentose phosphate shunt c. Entner-Doudoroff pathway d. Glyoxylate cycle

d. Glyoxylate cycle

A 30-year-old male was diagnosed with HIV. Which of the following treatments would be most effective? a. Reverse transcriptase inhibitors b. Protease inhibitors c. Entrance inhibitors d. Highly active antiretroviral therapy (HAART)

d. Highly active antiretroviral therapy (HAART)

A nurse recalls bacteria become resistant to antimicrobials by: a. Proliferation b. Attenuation c. Specialization d. Mutation

d. Mutation

Which of the following is NOT a function of the plasma membrane? a. Transport and permeability barrier b. Biosynthesis of DNA and cell wall components c. Energy transduction d. Osmotic resistance

d. Osmotic resistance

A bacterium with an outer membrane will contain ______ which makes it more resistant to antimicrobials and is the site of active transport mechanism. a. Teichoic acids b. Lipopolysaccharide c. Lipid A d. Periplasmic space e. Porins

d. Periplasmic space

A 40-year-old female is diagnosed with SLE. Which of the following findings would be considered a symptom of this disease? a. Gastrointestinal ulcers b. Decreased glomerular filtration rate c. Rash on trunk and extremities d. Photosensitivity

d. Photosensitivity

The microorganisms that make up the normal human flora are important for: a. Regulating inflammation b. Secreting bacteriostatic substances c. Activating white blood cells d. Preventing the colonization and multiplication of pathogens

d. Preventing the colonization and multiplication of pathogens

The following carries genes for replication and antibiotic resistance, but not for transfer: a. Fertility factors b. Resistance factors c. F' factors d. R determinants e. RTF factors

d. R determinants

_______ is an extremely rare and the most severe form of SCID that causes T and NK deficiencies with severe neutropenia and sensorineural deafness. It results from defects in mitochondrial metabolism especially due to an adenylate kinase 2 deficiency. Curative treatment relies on hematopoietic stem cell transplant (HSCT) a. Selective IgA immunodeficiency b. X-linked hyper-gamma-globulinemia c. DiGeorge's syndrome d. Reticular dysgenesis

d. Reticular dysgenesis

Abx functions in five major ways. Which of the following interferes with protein synthesis? a. Sulfonamides b. Polymyxins c. Penicillins d. Tetracyclines e. Quinolones

d. Tetracyclines

Heat shock response in bacteria is regulated by: a. Phase variation b. Antisense RNA c. Competitive binding of repressor protein d. Using alternative RNA polymerase sigma factor

d. Using alternative RNA polymerase sigma factor

A 25-year-old female reports having unprotected sexual intercourse with several men. Blood tests reveal that she is positive for human papillomavirus. What else should the nurse assess for? a. Vaginal discharge b. Liver failure c. Breast cancer d. Warts

d. Warts

Epinephrine: a. Causes bronchodilation b. Is effective even after anaphylactic sx commence c. Relaxes smooth muscle d. Decreases vascular permeability e. All of the above

e. All of the above


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