2nd MT

What is meant by semiconservative replication of DNA?

What is meant by semiconservative replication of DNA?

Each strand is the template for another strand.

In DNA sequencing, what is the purpose of the dideoxynucleotide bases?

• To enhance synthesis of DNA

• To stop growth of a DNA chain at a certain point

• To make certain that only one strand of DNA is amplified

• To create restriction fragment length polymorphisms

To stop the growth of a DNA chain at a certain point

Which method is most precise for detecting mutations?

a. qPCR

b. TMA

c. chain termination sequencing

d. RT-PCR

Chain termination sequencing

What process confers specificity in molecular biology methods?

Hybridization

Which characteristic does strand displacement amplification share with the polymerase chain reaction?

Both involve DNA polymerase.

Sanger chain termination sequencing differs from polymerase chain reaction because:

A. only one primer is used.
B. DNA polymerase is not needed.
C. the process is isothermal.
D. only three nucleotide bases are used.

A. only one primer is used.

Which method is utilized for HLA typing?

a. RT-PCR

b. TMA

c. SDA

d. NGS

NGS

Bioinformatics has been used in:

a. determining medical significance of variants.

b. storing DNA information only.

c. developing nomenclature for sequencing.

d. establishing of small storage of DNA data

determining the medical significance of variants.

1) The antibody found on mucosal surfaces that acts as a first line of defense is called:
A) IgA
B) IgD
C) IgE
D) IgM

A) IgA

1) Which antibody is found in the greatest supply and is the only one capable of crossing the placenta?
A) IgA
B) IgD
C) IgE
D) IgG

D) IgG

1) All of the following are characteristic of IgE EXCEPT:
A) found on mast cells and basophils
B) fixes complement
C) found in low amounts in the blood
D) causes allergic reactions

B) fixes complement

1) The antibody found on B cells that is thought to be involved in B cell maturation is:
A) IgA
B) IgD
C) IgE
D) IgM

B) IgD

1) The theory that lymphocytes are preprogrammed to respond to a particular type of antigen best describes:
A) the clonal selection theory
B) Ehrlich's side chain theory
C) the spontaneous generation theory
D) Edelman's antibody formation theory

A) the clonal selection theory

1) In serum protein electrophoresis, which band contains the immunoglobulins?
A) alpha-1
B) alpha-2
C) beta
D) gamma

D. gamma

1) Which of the following best characterizes IgD?
A) primary response antibody
B) surface receptor for antigen
C) responsible for allergic reactions
D) fixes complement

B) surface receptor for antigen

1) Where on an antibody molecule does combination with antigen take place?
A) variable region
B) constant region
C) hinge region
D) Fc region

A) variable region

1) All of the following are true of IgG EXCEPT:
A) first class of antibody to appear
B) able to cross the placental barrier
C) the predominant antibody in serum
D) provides immunity for the newborn

A) first class of antibody to appear

1) Which antibody is found mainly as a dimer in mucosal secretions?
A) IgA
B) IgD
C) IgE
D) IgG

A) IgA

1) IgG differs from IgM in which way?
A) IgM can cross the placenta.
B) IgG can bind more antigens than IgM.
C) IgG is the main antibody in serum.
D) Only IgM has kappa light chains.

C) IgG is the main antibody in serum.

1) The primary response differs from the secondary immune response in what way?
A) Amounts of IgG and IgM are the same.
B) The lag time is shorter.
C) Amounts of IgG increase greatly.
D) More memory cells are involved.

A) Amounts of IgG and IgM are the same.

1) Cytokines exhibit pleiotropy, which refers to:
A) multiple cytokines affecting the same cell
B) one cytokine inhibiting the activity of another cytokine
C) one cytokine affecting multiple cells
D) cytokines acting together to affect a cell

C) one cytokine affecting multiple cells

1) IL-2 is synthesized by which type of cell and acts on which type of cell?
A) TH1; CTL
B) TH2; CTL
C) TH2; NK
D) TH1; mast cells

A) TH1; CTL

214) A cytokine that is produced by TH2 cells and inhibits TH1 cells is:
A. IL-10
B. IL-4
C. IL-3
D. IFN-gamma

A. IL-10

215) IL-1, IL-6, and tumor necrosis factor-alpha function by:
A. increasing vascular permeability
B. increasing acute phase proteins
C. acting on the hypothalamus
D. promoting migration of inflammatory cells
E. all of these

E. all of these

216) IL-3, IL-7, and GM-CSF are all involved in:
A. hematopoiesis
B. suppressing inflammation
C. macrophage killing
D. T cell cytotoxicity

A. hematopoiesis

217) IL-2 is produced by one cell and the same IL-2 stimulates that same cell. This type of cytokine activity is called:
A. autocrine
B. paracrine
C. endocrine
D. pleotropic

A. autocrine

218) IL-2 is a cytokine that could be more specifically called which of the following because of the cells that produce it?
A. lymphokine
B. monokine
C. basokine
D. eokine

A. lymphokine

219) IL-4 functions by:
A. inhibiting macrophages
B. inducing hematopoiesis
C. activating B cells
D. activating macrophages

C. activating B cells

220) IFN-gamma is produced by:
A. B cells
B. TH1 cells
C. TH2 cells
D. macrophages

B. TH1 cells

221) When multiple cytokines act on the same cell, by definition they have:
A. pleiotropy
B. redundancy
C. synergism
D. antagonism

B. redundancy

222) Which of the following cytokines is produced by TH1 cells and is suppressive for TH2 lymphocytes?
A. IL-2
B. IL-4
C. TGF-beta
D. IFN-gamma

D. IFN-gamma

223) All of the following are actions of interleukin-1 EXCEPT:
A. increased synthesis of acute phase reactants
B. attraction of white cells to the area
C. increased production of IgE
D. acts as an endogenous pyrogen

C. increased production of IgE

224) A protein released from a virally infected cell that protects other cells from viral invasion best describes:
A. Il-3
B. interferon-alpha
C. TNF
D. IL-4

B. interferon-alpha

225) When Il-2 acts on T cells, B cells, and NK cells, this is an example of:
A. redundancy
B. pleiotropy
C. synergy
D. antagonism

B. pleiotropy

226) The actions of IL-1 and IL-10 are an example of:
A. redundancy
B. antagonism
C. synergy
D. pleiotropy

B. antagonism

227) What is the main function of chemokines?
A. inhibit the immune response
B. enhance synthesis of acute phase reactants
C. enhance migration of white blood cells
D. protect cells from viral invasion.

C. enhance migration of white blood cells

228) What is the main action of interferon-gamma?
A. increased synthesis of acute phase reactants
B. stimulation of T cells
C. inhibition of T cell activity
D. activation of macrophages

D. activation of macrophages

229) What is the function of TGF-alpha?
A. helps in antibody-mediated immunity
B. regulates cell growth and differentiation
C. inhibits IL-2
D. acts as an endogenous pyrogen

B. regulates cell growth and differentiation

230) The main target of interleukin-3 is:
A. antigen-activated B cells
B. antigen-activated T cells
C. macrophages
D. stem cells

D. stem cells

231) Which cytokine is involved in natural immunity?
A. interleukin-6
B. interleukin-2
C. interleukin-4
D. interleukin-5

A. interleukin-6

232) Which cells produce interleukin-1?
A. T helper cells
B. cytotoxic T cells
C. B cells
D. macrophages

D. macrophages

233) Erythropoietin is classified as which of the following?
A. T-cell regulator
B. colony-stimulating factor
C. proinflammatory cytokine
D. regulator of the acute phase response

B. colony-stimulating factor

234) Which acts as the best defense against gram-negative bacteria?
A. IL-1
B. TNF
C. IL-2
D. IL-5

B. TNF

235) Which of the following can be attributed to interleukin-6 (IL-6)?
A. stimulates red blood cell production
B. increases vascular permeability
C. inhibits antigen presentation by macrophages
D. increases activation of T and B cells

D. increases activation of T and B cells

236) Which best describes the nature of interleukin-2?
A. activates T helper cells
B. made by macrophages
C. causes lysis of tumor cells
D. down-regulates the immune response

A. activates T helper cells

237) What is one of the main activities of interleukin-4 (IL-4)?
A. downregulation of the immune response
B. increased production of neutrophils
C. generation of TH2 cells
D. protecting cells from viral invasion

C. generation of TH2 cells

238) Which complement component is found in both the classic and alternative pathways?
A. C1
B. C2
C. factor B
D. C3

D. C3

239) Which of the following is a characteristic of complement?
A. It is activated by IgE in the classical pathway.
B. It cannot be activated by molecules other than antigen-antibody complexes.
C. It plays a role in the lysis of target cells coated with specific antibodies.
D. It is enhanced by decay accelerating factor.

C. It plays a role in the lysis of target cells coated with specific antibodies.

240) Which of the following can activate the alternative complement pathway?
A. IgG
B. mannose-binding lectin
C. C3b
D. C1q

C. C3b

241) Which of the following functions by inserting itself into target membranes and forming channels or holes in the membranes?
A. C3bBb3b
B. C4b2a
C. C5b6789
D. C3b

C. C5b6789

242) Which of the following act as opsonins?
A. IgD
B. C3b
C. C5a
D. IL-2

B. C3b

243) The C5 convertase of the alternative pathway of complement activation is:
A. C4b
B. C4b2a
C. C4b2a3b
D. C3bBb3bP

D. C3bBb3bP

244) C5b6789 functions in:
A. target cell lysis
B. recognition of antigen
C. chemotaxis
D. complement inhibition

A. target cell lysis

245) The functions of C5a are to promote all of the following EXCEPT:
A. phagocytosis of target cells
B. contraction of smooth muscle
C. increased vascular permeability
D. leukocyte attraction to the site of inflammation

A. phagocytosis of target cells

246) Chemotactic and anaphylactic factors are produced by proteolytic cleavage of:
A. C1q, C1r, C1s
B. C4, C2
C. C5, C3
D. C5, C6, C7, C8

C. C5, C3

247) The alternative and classical pathway C3 convertases are destabilized as a means of down-regulating complement function. One molecule that performs this function is:
A. C1 esterase inhibitor
B. membrane cofactor protein
C. complement receptors 1 and 2
D. CD59

B. membrane cofactor protein

248) What is cleaved by C3bBb?
a) C3
b) C5
c) C6

a) C3

249) Which of the following is the correct order of activation of complement in the lectin activation pathway?
a) C1, C4, C2, C3
b) MBL, C4, C2, C3
c) C3, factor B, C3
d) MBL, C2, C3, C4

b) MBL, C4, C2, C3

250) A native bacterial cell surface itself will activate complement via which pathway(s)?
A. classical
B. alternative
C. lectin
D. two of these
E. all of these

D. two of these

251) Which of the following is cleaved first by C1qrs in the classical pathway of complement activation?
A. C2
B. C3
C. C4
D. factor B

C. C4

252) Which of the following complement components has chemotactic activity?
A. C3b
B. C3a
C. C1qrs
D. C5b6789

B. C3a

253) The C3 convertase of the alternative pathway of complement activation is:
A. C3bBbP
B. C3bB
C. C4b2a3b
D. C4b2a

A. C3bBbP

254) The target recognition molecule of the lectin pathway that initiates complement activation is:
A. C1q
B. C4
C. C5b6789
D. mannose-binding lectin

D. mannose-binding lectin

255) Which immunoglobulin(s) help(s) initiate the classic complement pathway?
A. IgA and IgD
B. IgM only
C. IgG and IgM
D. IgG only

C. IgG and IgM

256) Which of the following has perforin-like activity?
A. IgG
B. IFN-gamma
C. C5b6789
D. C3b

C. C5b6789

257) What is cleaved by C4b2a3b?
A. C3
B. C4
C. C5
D. C6

C. C5

258) A patient has an abnormal alternative pathway activation pattern. Which of the following complement proteins should be assessed to further elucidate the problem?
a) C1
b) C2
c) C3
d) C4

c) C3

259) The C5 convertase of the classical pathway of complement activation is:
A. C3bBbP
B. C3bBb3bP
C. C4b2a3b
D. C4b2a

C. C4b2a3b

260) A deficiency in complement component C2 would result in:
A. increased vascular permeability
B. hereditary angioedema
C. severe infections with encapsulated bacteria
D. immune complex disease

D. immune complex disease

261) Which of the following represents C3 convertase?
A. C4b2a
B. C3bBbP
C. C1qrs
D. A and B
E. A and C

D. A and B

262) Which factors are only associated with the alternative pathway?
A. factor B and factor D
B. factor D and C3
C. factor B and C2
D. C2 and MBL

A. factor B and factor D

263) The lectin pathway is initiated by the presence of which of the following?
A. antibody
B. C3
C. Mannose
D. C1qrs

C. Mannose

264) The membrane attack unit of complement is represented by which of the following?
A. C2a4b3b
B. C1qrs
C. C3bBbP
D. C5b6789

D. C5b6789

265) Which complement factor polymerizes to cause lysis of a foreign cell?
A. C5
B. C6
C. C8
D. C9

D. C9

267) Binding of a lectin to a sugar found in bacteria and fungi occurs in which complement pathway?
A. alternative pathway
B. classical pathway
C. MBL pathway
D. all of the above

C. MBL pathway

268) Which factor is unique to the lectin pathway?
A. Factor B
B. C1q
C. Mannose-binding protein
D. Factor I

C. Mannose-binding protein

Lack of the complement inhibitor C1INH results in which disease?
A. Hereditary angioedema
B. Paroxysmal nocturnal hemoglobinuria
C. Immune complex disease
D. meningitis

A. Hereditary angioedema

270) All of the following can trigger the alternative pathway EXCEPT:
A. fungal cell walls
B. bacterial cell walls
C. yeast
D. antibody

D. antibody

271) In the alternative pathway, C3 and C5 convertase are stabilized by which of the following?
A. Properdin
B. Factor B
C. Factor I
D. C4

A. Properdin

272) Which factors are found in all three pathways?
A. Factors B and D
B. C4, C2, C3
C. C5-C9
D. C1qrs, C3, C5

C. C5-C9

274) Which complement protein is the key intermediate in all pathways?
A. C4
B. C2
C. C3
D. C1

C. C3

275) In the alternate pathway, factor B must bind to which of the following to initiate the cascade?
A. Factor I
B. C3b
C. C4b
D. properdin

B. C3b

276) Which factor must be associated with factor H to inactivate complement components?
A. C1INH
B. Factor I
C. DAF
D. CR1

B. Factor I

277) Lack of the complement components C5-C* may result in which disease?
A. Hereditary angioedema
B. Paroxysmal nocturnal hemoglobinuria
C. Atherosclerosis
D. meningitis

A. Hereditary angioedema

278) Which factor helps to dissociate C3b from red blood cells?
A. Factor B
B. DAF
C. C1INH
D. C5

B. DAF

279) Which protein inhibits the classical complement pathway at the very beginning of it?
A. C1INH
B. C4BP
C. C3BP
D. Factor H

A. C1INH

280) Which of the following are important functions of the complement system?
A. Lysis of foreign cells
B. Increase in vascular permeability
C. Clearance of antigen-antibody complexes
D. All the above
E. All except one of the above

D. All the above

281) Formation of the membrane attack complex (C5b-C9) is stopped by which factor?
A. Factor H
B. Factor I
C. C1INH
D. S protein

D. S protein

282) Which is characteristic of complement components?
A. All are active enzymes.
B. They are synthesized only when antigen is present.
C. They play a major part in the inflammatory response.
D. They are mainly produced in lymphoid tissue.

C. They play a major part in the inflammatory response.

283) C4BP acts in association with which factor to inactivate C4b?
A. Factor B
B. Factor D
C. Factor I
D. C1INH

C. Factor I

284) All of the following statements are true of C3 except
A. It is known as the recognition unit.
B. It plays a key role in all pathways.
C. It is the most abundant of the complement proteins.
D. Its major function is opsonization.

A. It is known as the recognition unit.

285) Which of the following is referred to as C5 convertase?
A. C4b2a
B. MASP1
C. C4b2a3b
D. C1qrs

C. C4b2a3b

286) Which of the following activities is associated only with the alternative pathway of complement fixation?
A. Formation of a membrane attack unit
B. Factor B and C3b combination
C. Antigen-antibody combination
D. lysis

B. Factor B and C3b combination

287) A system of serum proteins that interact to enhance the immune response by producing cytolytic, chemotactic, and other effects best describes:
A. complement
B. fibrinogen
C. haptoglobin
D. CRP

A. complement

The proteins of the complement system are part of:

• adaptive immunity immunologic memory.

• phagocytosis.

• innate immunity.

• B-cell formation.

Innate immunity

Which of the following is a characteristic of complement?

1. It is activated by IgE in the classical pathway

2. It cannot be activated by molecules other than antigen-antibody complexes

3. It plays a role in the lysis of target cells coated with specific antibodies

4. It is enhanced by decay accelerating factor

It plays a role in the lysis target cells coated with specific antibodies

Complement is essential for our body's response to infection, by being heavily involved in:

a. phagocytosis

b. inflammation

c. T-cell activation

d. B-cell differntiation

Inflammation

Which complement component is found in both the classical and alternative pathways?

C1, C2, Factor B, C3

C3

Which of the following can activate the alternative complement pathway?

C3b

Which of the following is the correct order of activation of complement in the lectin activation pathway?

MBL, C4, C2, C3