Blood Composition and Key Parameters
48 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What role does RAG recombinase play in the B cell development process?

  • Facilitates heavy chain assembly
  • Helps in recombination of B cell receptors (correct)
  • Promotes B cell survival
  • Ensures lineage commitment

    • What is the primary outcome for immature B cells that remain reactive during negative selection?

  • They are eliminated through apoptosis (correct)
  • They are transformed into T cells
  • They migrate to peripheral circulation
  • They undergo receptor editing

    • Which B cell type is predominantly T-dependent and responds to diverse protein antigens?

  • Memory B Cells
  • B-1 Cells
  • Mature Naïve B Cells (correct)
  • Marginal Zone B Cells

    • What is the consequence of a defective Btk in B cell development?

    <p>Progression to mature B cells is halted</p> Signup and view all the answers

    Which characteristic is associated with autoreactive B cells that escape the bone marrow?

    <p>Short half-life of 1-5 days</p> Signup and view all the answers

    What begins with the rearrangement of the λ light chain locus in the pre-B cell stage?

    <p>Light chain rearrangement</p> Signup and view all the answers

    Which B cell type is characterized by high CD21 levels and a rapid response to blood-borne pathogens?

    <p>Marginal Zone B Cells</p> Signup and view all the answers

    What initiates the survival signaling during the pre-B cell stage?

    <p>Pairing of surrogate light chain with heavy chain</p> Signup and view all the answers

    What is the primary issue in Selective IgA Deficiency?

    <p>B cells expressing surface IgA fail to develop into plasma or memory cells.</p> Signup and view all the answers

    What is the purpose of V(D)J recombination in T cells?

    <p>To generate diversity and specificity for antigen recognition.</p> Signup and view all the answers

    Which treatment is commonly associated with Common Variable Immunodeficiency (CVID)?

    <p>IVIG and antibiotics.</p> Signup and view all the answers

    Which chains are involved in the somatic recombination of T cell receptors?

    <p>α and β chains.</p> Signup and view all the answers

    Which of the following is a life-threatening condition in infancy associated with SCID?

    <p>Recurrent severe infections.</p> Signup and view all the answers

    Which genetic mutation accounts for approximately 12% of SCID cases?

    <p>JAK3 tyrosine kinase mutation.</p> Signup and view all the answers

    What does the class I MHC molecule consist of?

    <p>α-heavy chain, β2-microglobulin, and a peptide.</p> Signup and view all the answers

    What organ defect is commonly associated with DiGeorge Syndrome?

    <p>Thymus.</p> Signup and view all the answers

    What is the role of CD4 in MHC class II interactions?

    <p>To bind the β2 domain of MHC class II.</p> Signup and view all the answers

    What role does AID play in somatic hypermutation?

    <p>Converts cytosine to uracil in single-stranded DNA.</p> Signup and view all the answers

    What is the consequence of a deficiency in complement proteins such as C1, C2, or C4?

    <p>Decreased removal of immune complexes, leading to autoimmunity.</p> Signup and view all the answers

    What is primarily processed in the endocytic pathway for MHC class II presentation?

    <p>Extracellular proteins.</p> Signup and view all the answers

    What is the main outcome of class switching mediated by AID?

    <p>Adaptation of antibodies to perform diverse immune functions.</p> Signup and view all the answers

    Which condition is specifically prevented by defects in complement regulatory proteins?

    <p>Paroxysmal nocturnal hemoglobinuria.</p> Signup and view all the answers

    Which statement about the classes of TCRs is correct?

    <p>α:β T cells account for 95% of T cells.</p> Signup and view all the answers

    What is a common symptom of typical SCID?

    <p>Failure to thrive.</p> Signup and view all the answers

    What type of enzymes are involved in the joining phase of V(D)J recombination?

    <p>Double-strand break repair enzymes.</p> Signup and view all the answers

    What characterizes CD40L deficiency in terms of clinical symptoms?

    <p>Elevated levels of IgM and enlarged lymph nodes.</p> Signup and view all the answers

    Which statement is true regarding AID deficiency?

    <p>It results in disabled somatic hypermutation and class switching.</p> Signup and view all the answers

    Which of the following is a function of professional antigen-presenting cells (APCs)?

    <p>Activate and differentiate naïve T cells.</p> Signup and view all the answers

    What key function is associated with TH2 cells in the immune response?

    <p>Eosinophil activation</p> Signup and view all the answers

    Which autoimmune disorder risk is associated with errors in affinity maturation?

    <p>Increased production of self-reactive antibodies.</p> Signup and view all the answers

    What are the implications of germinal centers in B-cell lymphomas?

    <p>They are areas of high proliferation that can lead to malignancies.</p> Signup and view all the answers

    Which cytokine is primarily associated with the activation of macrophages?

    <p>IFN-γ</p> Signup and view all the answers

    What differentiates Central Memory T Cells from Effector Memory T Cells?

    <p>Effector Memory T Cells lack CCR7 and CD62L</p> Signup and view all the answers

    In the structure of a T cell receptor (TCR), what domain is specifically known for high variability?

    <p>Vβ domain</p> Signup and view all the answers

    How do T cell receptors (TCRs) compare to B cell receptors (BCRs)?

    <p>TCRs share structural similarities with the Fab region of immunoglobulins.</p> Signup and view all the answers

    What is the significance of memory T cells in the secondary immune response?

    <p>They ensure faster clonal expansion upon re-exposure to antigen.</p> Signup and view all the answers

    Which statement regarding antibody dynamics is correctly described in the context of the immune response?

    <p>IgM initiates the response but has low-affinity.</p> Signup and view all the answers

    Which key cytokines do TFH cells secrete to regulate B cell development?

    <p>IL-21 and IL-6</p> Signup and view all the answers

    Which of the following correctly explains a function of TH17 cells?

    <p>Epithelial barrier maintenance and inflammation</p> Signup and view all the answers

    What is the role of CD45 isoforms in T cell differentiation?

    <p>They distinguish between naïve, effector, and memory T cells.</p> Signup and view all the answers

    What is the role of effector T cells in relation to macrophages and B cells?

    <p>They stimulate macrophages and B cells to produce cytokines or antibodies.</p> Signup and view all the answers

    How are MHC genes expressed in offspring?

    <p>MHC genes are co-dominantly expressed from both parents.</p> Signup and view all the answers

    What initiates T-cell lineage commitment during development?

    <p>Interaction with thymic stromal cells and IL-7.</p> Signup and view all the answers

    What is the fate of the majority of thymocytes during T-cell development?

    <p>They undergo apoptosis due to unsuccessful TCR rearrangement.</p> Signup and view all the answers

    What occurs during positive selection in T-cell development?

    <p>Weak binding may result in further α chain rearrangement.</p> Signup and view all the answers

    What is the impact of successful β chain rearrangement in T-cell development?

    <p>It halts γδ rearrangement and initiates CD4/CD8 expression.</p> Signup and view all the answers

    What is the role of the AIRE transcription factor during negative selection?

    <p>It induces tissue-specific antigen expression in medullary epithelial cells.</p> Signup and view all the answers

    What characterizes Class II MHC expression?

    <p>Expressed on antigen-presenting cells (APCs).</p> Signup and view all the answers

    Study Notes

    Blood Composition and Key Parameters

    • Erythrocytes (red blood cells) make up 45% of blood volume. They are anucleate and lack organelles, mainly transporting oxygen and carbon dioxide via hemoglobin. They have a lifespan of about 120 days. Genetic diseases like hereditary spherocytosis or elliptocytosis are associated with mutations affecting their shape and flexibility.

    • Leukocytes (white blood cells) represent 1-2% of blood volume. They are categorized as granulocytes (neutrophils, eosinophils, basophils) or agranulocytes (lymphocytes, monocytes). A complete blood count (CBC) provides information about cell counts, including mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and red cell distribution width (RDW).

    • Plasma constitutes 53-54% of blood volume and is the liquid portion of blood. Hematocrit measures the percentage of red blood cells in the blood volume. Values vary by sex.

    Leukocytes (WBCs)

    • Neutrophils (PMNs) are multi-lobed granulocytes, with primary (azurophilic), secondary (specific), and tertiary granules. They are first responders to infection, exhibit diapedesis (exiting blood vessels), and phagocytose pathogens. Synthesis of reactive oxygen species (ROS) contributes to killing pathogens. The phagocyte oxidase and myeloperoxidase systems are involved.

    • Eosinophils are bilobed granulocytes; they are involved in defense against parasites and allergic reactions, and release enzymes like histaminase.

    • Basophils contain granules that stain with basic dyes, masking their bilobed nuclei. Basophils contain heparin, histamine, and cytokines; involved in hypersensitivity and anaphylaxis.

    • Lymphocytes are agranulocytes; T-cells are involved in cellular immunity and CD3 positive. CD8+ T cells are cytotoxic and recognize MHC I. CD4+ T cells are helper cells that recognize MHC II, and regulate tolerance via regulatory T cells (Tregs). γδ T cells mediate epithelial defense, while B-cells mediate humoral immunity, differentiate into plasma cells, and produce antibodies. NK cells recognize and kill virally infected cells and tumors.

    • Monocytes are the largest leukocytes; they are agranular and have indented nuclei. They circulate for 3 days before becoming macrophages in tissues, mediating phagocytosis and antigen presentation.

    Hematopoiesis

    • Erythropoiesis (red blood cell production) proceeds through stages, including proerythroblast, basophilic erythroblast, polychromatophilic erythroblast (normoblast), polychromatophilic erythrocyte (reticulocyte), and finally, erythrocyte.

    • Granulopoiesis (granulocyte production) involves stages from CMP (common myelocytic progenitor) to myeloblast, promyelocyte, myelocyte, metamyelocyte, and mature granulocytes. Neutrophils, eosinophils, and basophils stem from the GMP (granulocyte/monocyte progenitor).

    • Monopoiesis begins with GMP → MoP (monocyte precursor) to develop mature monocytes, which circulate for 3 days before differentiation into macrophages.

    • Thrombopoiesis: CMP differentiates into MEP (megakaryocyte-erythroid progenitor) to megakaryoblast and megakaryocyte, eventually shedding platelets into the circulation. Platelets are involved in clot formation and wound repair.

    Stem Cells

    • Stem cells: Totipotent (e.g., zygote), pluripotent (e.g., embryonic stem cells), multipotent (e.g., hematopoietic stem cells), and unipotent (e.g., testis stem cells) are capable of generating different cell types

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Unit 1 - Immunology HYFS PDF

    Description

    This quiz focuses on the composition of blood, specifically erythrocytes, leukocytes, and plasma. You'll explore the functions, characteristics, and key parameters associated with these blood components. Test your understanding of blood volume percentages and related genetic conditions.

    More Like This

    MedCa Phlebotomy Certification Exam Overview
    43 questions

    MedCa Phlebotomy Certification Exam Overview

    WorthSpruce672 avatar
    WorthSpruce672
    Blood Composition and Functions
    19 questions

    Blood Composition and Functions

    VibrantConcertina avatar
    VibrantConcertina
    Human Blood Components Quiz
    98 questions

    Human Blood Components Quiz

    CongratulatoryActionPainting avatar
    CongratulatoryActionPainting
    Blood
    5 questions

    Blood

    WellKnownLaplace7726 avatar
    WellKnownLaplace7726
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser