Practice 8 MCQs on Comprehensive Immunology Quiz with OmpathStudy. Built for Kenyan medical and health students to revise key concepts and prepare for exams.
Q1. .2 Which of the following is only contained in heavy chains and not in light chains? a) Leader (L)b) Joining (J)c) Diversity (D) d) Variable (V)e) Constant (
Answer: Variable (V)e) Constant
Q2. .1 During the development of B cells, the Ig gene segments are rearranged and brought next to each other to form a contiguous functional gene (somatic recombination). The complex of enzymes involved in somatic recombination in lymphocytes is called: a) RAG-1 (Recombination-Activating Gene)b) RAG-2 (Recombination-Activating Gene)c) V(D) J-recombinased) V(
Answer: J-recombinased) V
Q3. .1 Which of the following diseases occurs with the absence of a thymus? a) DiGeorge's syndromeb) Severe combined immunodeficiency disease (SCID) c) Chronic granulomatous disease (CG
Answer: Chronic granulomatous disease (CG
Explanation: DiGeorge syndrome is caused by developmental abnormalities affecting the third and fourth pharyngeal pouches, leading to absent or underdeveloped thymus and parathyroid glands.
Q4. .2 Which of the following diseases affect neutrophils? a) DiGeorge's syndromeb) Severe combined immunodeficiency disease (SCID) c) Chronic granulomatous disease (CG
Answer: Chronic granulomatous disease (CG
Explanation: CGD affects neutrophil function, specifically their ability to produce reactive oxygen species needed to kill certain bacteria and fungi.
Q5. .3 Which of the following diseases affects mature T cells? a) DiGeorge's syndromeb) Severe combined immunodeficiency disease (SCID) c) Chronic granulomatous disease (CG
Answer: Chronic granulomatous disease (CG
Explanation: BLS affects the expression of MHC molecules on mature T cells, preventing proper antigen presentation and T cell function.
Q6. .6 A child presents with recurrent infections with bacteria, fungi, and viruses. The resident asks the attending physician about IL-2R γ chain mutations, as the patient is a male. The attending physician makes a diagnosis and begins writing orders for bone marrow transplantation and possible gene therapy. Which of the following does the patient have? a) Ataxia telangiectasiab) Wiscott-Aldrich syndrome (WAS)c) Hereditary angioedemad) Severe combined immunodeficiency disease (SCID)e) C3 deficiency Correct Answer: D) Severe combined immunodeficiency disease (SCI
Answer: C3 deficiency
Explanation: X-linked SCID is caused by IL-2Rγ chain mutations, affecting both T and B cell function. The severity requires immediate bone marrow transplantation.
Q7. .7 A young child presents with cervical adenitis and gingivostomatitis. History reveals recurrent pyogenic infections. Tests are done to determine leukocytosis and the presence of cell adhesion molecules. Which of the following is the most likely? a) C3 deficiencyb) Wiscott-Aldrich syndrome (WAS)c) Leukocyte adhesion deficiency (LAD)d) Hyper IgM syndrome (HIM)e) Selective IgA deficiency Correct Answer: C) Leukocyte adhesion deficiency (LA
Answer: Hyper IgM syndrome (HIM)e) Selective IgA deficiency
Explanation: LAD patients have defective neutrophil adhesion and migration, leading to recurrent bacterial infections and characteristic gingivostomatitis without pus formation.
Q8. .10 A male patient presents with severe and recurrent bacterial infections. Lab work confirms the patient is only infected with certain bacteria due to a mutation in a gene for NADPH oxidase. Which of the following is the most likely? a) DiGeorge's syndromeb) Chediak-Higashi disorderc) Bare lymphocyte syndrome (BLS)d) Wiskott-Aldrich syndrome (WAS)e) Chronic granulomatous disease (CGD) Correct Answer:
Answer: **Correct Answer:
Explanation: CGD is caused by mutations in NADPH oxidase components, preventing neutrophils from producing reactive oxygen species needed to kill catalase-positive bacteria.