MCAT immune system cells study guide
A comprehensive study guide for the MCAT covering key immune system cells, their functions, interactions, and relevance in human physiology.
Quiz(64 questions)
1. What is the primary cause of autoimmune diseases?
Terms in this Study Set(64)
Innate Immunity Cells(16)
What is the primary role of neutrophils?
First responders to infection; engulf pathogens via phagocytosis.
True or False: Macrophages only respond to viral infections.
False. They respond to bacterial, viral, and fungal infections.
Fill in the blank: Mast cells release __________ during allergic reactions.
histamine and other mediators.
Compare dendritic cells and macrophages.
Dendritic cells: antigen presentation to T cells. Macrophages: phagocytosis and cytokine release.
What cell type is responsible for the production of histamine?
Mast cells.
Natural killer (NK) cells primarily target which type of cells?
Virus-infected and tumor cells.
True or False: Eosinophils are involved in defense against parasites.
True. They combat larger parasites and mediate allergic responses.
What is the function of basophils?
Release histamine and promote inflammatory responses.
What do phagocytes do?
Engulf and digest pathogens and debris.
True or False: Innate immunity has memory.
False. Innate immunity is non-specific and does not have memory.
What are the key differences between innate and adaptive immunity?
- Innate: non-specific, immediate response. - Adaptive: specific, slower response, has memory.
What triggers the activation of NK cells?
Recognition of stressed or infected cells lacking MHC class I.
Fill in the blank: Neutrophils primarily kill pathogens using __________.
reactive oxygen species (ROS) and enzymes.
How do macrophages process antigens?
They phagocytize pathogens, process them, and present on MHC molecules.
What role do cytokines play in innate immunity?
They mediate communication between immune cells, inducing inflammation.
What is the lifespan of neutrophils in tissues?
Short-lived, typically a few hours to a few days.
Adaptive Immunity Cells(16)
What are B cells responsible for?
B cells produce antibodies, providing humoral immunity by targeting specific antigens.
True or False: T cells are involved in humoral immunity.
False. T cells primarily mediate cell-mediated immunity, while B cells handle humoral immunity.
Fill in the blank: Memory cells are a type of ___ cell.
B cell or T cell.
Compare B cells and T cells.
B cells: produce antibodies; T cells: directly kill infected cells or help other immune cells.
What are the two main types of T cells?
1. Cytotoxic T cells (CD8+) 2. Helper T cells (CD4+)
Cause → Effect: Activation of T cells leads to ___ .
Proliferation and differentiation into effector T cells.
True or False: Antibodies can neutralize pathogens.
True. Antibodies bind to antigens, neutralizing pathogens and marking them for destruction.
What is the role of helper T cells?
They assist in activating B cells and cytotoxic T cells, enhancing immune response.
What do plasma cells do?
Plasma cells are differentiated B cells that produce large quantities of antibodies.
Fill in the blank: T cells recognize antigens presented by ___ molecules.
MHC (Major Histocompatibility Complex) molecules.
What is clonal selection?
Clonal selection is the process of selecting B or T cells that specifically recognize an antigen.
List two functions of antibodies.
1. Neutralization of pathogens 2. Opsonization to enhance phagocytosis
True or False: All memory cells are long-lived.
True. Memory cells can persist for years, providing long-lasting immunity.
Cause → Effect: Exposure to a pathogen triggers ___ .
Activation and proliferation of specific B and T cells.
What is the difference between active and passive immunity?
Active immunity: body produces antibodies after exposure to an antigen. Passive immunity: antibodies are transferred from another source.
What are regulatory T cells?
Regulatory T cells help maintain immune tolerance and prevent autoimmune responses.
Cytokines and Immune Signaling(16)
What are cytokines?
Cytokines are signaling molecules that mediate communication between immune cells, influencing cell behavior, activation, and differentiation.
True or False: Cytokines only promote inflammation.
False. Cytokines can both promote and inhibit inflammation.
Interleukins (IL): Function?
- Mediate communication between leukocytes - Promote cell growth, differentiation, and activation.
Fill in the blank: TNF-α stands for __________.
Tumor Necrosis Factor-alpha.
Cytokine example: IL-1 role?
IL-1 promotes inflammation and activates T cells.
Compare: IL-2 vs IL-10.
IL-2: Stimulates T cell proliferation. IL-10: Anti-inflammatory and inhibits cytokine production.
What is the role of chemokines?
Chemokines are a subset of cytokines that direct the migration of immune cells to sites of inflammation.
True or False: All cytokines have the same effect on immune cells.
False. Cytokines can have different effects depending on the context and target cells.
Function of interferons (IFNs)?
Interferons enhance antiviral responses, activate immune cells, and inhibit viral replication.
What is the primary function of TGF-β?
Transforming Growth Factor-beta (TGF-β) regulates immune responses, promoting tolerance and inhibiting inflammation.
Cause → Effect: IL-6 secretion leads to __________.
Increased production of acute-phase proteins and fever.
What do growth factors do?
Growth factors stimulate cell growth, differentiation, and survival, affecting immune cell development.
Fill in the blank: The main source of IL-1 is __________.
Macrophages.
True or False: Cytokines can function in both autocrine and paracrine signaling.
True. Cytokines can act on the same cell (autocrine) or nearby cells (paracrine).
Role of GM-CSF?
Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) stimulates the production of granulocytes and macrophages.
What is the effect of cytokines on the blood-brain barrier?
Cytokines can increase permeability, allowing immune cells access to the central nervous system.
Immune System Disorders(16)
What is autoimmune disease?
A disease where the immune system attacks healthy cells as if they were foreign. Examples: rheumatoid arthritis, lupus.
True or False: Allergies are overreactions of the immune system.
True. Allergies occur when the immune system responds excessively to harmless substances, releasing histamines.
Fill in the blank: In ________, the immune system mistakenly attacks the thyroid gland.
Hashimoto's thyroiditis.
Comparison: Allergic reaction vs. Autoimmune response.
Allergic reaction: Overreaction to allergens. Autoimmune response: Attack on self-tissues.
What is SCID?
Severe Combined Immunodeficiency, a genetic disorder causing severely impaired immune response due to absence of T and B cells.
Cause → Effect: HIV infection leads to ________.
A weakened immune system, resulting in increased susceptibility to opportunistic infections.
What characterizes systemic lupus erythematosus?
A chronic autoimmune disease affecting multiple organ systems, characterized by periods of flare-ups and remission.
True or False: Vaccines can cause autoimmune diseases.
False. Vaccines are designed to stimulate immune protection without causing autoimmunity.
What is anaphylaxis?
A severe allergic reaction that can be life-threatening, resulting in symptoms like difficulty breathing, swelling, and drop in blood pressure.
Role of regulatory T cells in autoimmunity?
Regulatory T cells help maintain tolerance to self-antigens, preventing autoimmune responses.
Fill in the blank: Multiple sclerosis is characterized by ________.
Demyelination of nerve fibers in the central nervous system.
Comparison: Type I vs. Type II hypersensitivity.
Type I: Immediate reaction (e.g., allergies). Type II: Antibody-mediated cell destruction (e.g., hemolytic anemia).
What is the significance of the HLA gene?
Human Leukocyte Antigen genes are crucial for immune system recognition of self versus non-self.
Cause → Effect: Chronic stress can lead to ________.
Immunosuppression, increasing susceptibility to infections and possibly autoimmune disorders.
What is rheumatoid arthritis?
An autoimmune disorder characterized by chronic inflammation of joints, leading to pain and disability.
True or False: All immune system disorders are hereditary.
False. While some are genetic, many are acquired or caused by environmental factors.
Questions in this Study Set(64)
1. What is the primary cause of autoimmune diseases?
2. What is the primary function of cytokines in the immune response?
3. What is the primary function of neutrophils in the immune response?
4. What type of immunity do B cells primarily provide?
5. True or False: Allergies are a type of autoimmune disorder.
6. True or False: Cytokines can only inhibit immune responses.
7. True or False: Basophils play a central role in fighting viral infections.
8. True or False: Cytotoxic T cells are primarily responsible for activating B cells.
9. Fill in the blank: In ________, the body produces antibodies against its own tissues, leading to inflammation and damage.
10. Which interleukin is primarily responsible for stimulating T cell proliferation?
11. Fill in the blank: Eosinophils are especially important for combating __________ infections.
12. Fill in the blank: The primary function of plasma cells is to produce ___ .
13. Which of the following is NOT considered an autoimmune disorder?
14. Fill in the blank: IL-10 is known as a __________ cytokine.
15. Which cell type is primarily responsible for antigen presentation?
16. Which of the following correctly compares B cells and T cells?
17. Which immune cells are most affected in Severe Combined Immunodeficiency (SCID)?
18. Which cytokine is primarily involved in the activation of macrophages?
19. What is the main role of macrophages in the immune system?
20. What are the two major types of T cells?
21. What is the result of untreated HIV infection on the immune system?
22. What is the role of chemokines in the immune system?
23. Natural killer (NK) cells primarily target which of the following?
24. Cause → Effect: Activation of helper T cells leads to ___ .
25. Which condition involves a chronic autoimmune attack on the myelin sheath of neurons?
26. True or False: All cytokines have the same effect regardless of the target cells.
27. True or False: Mast cells release histamine as a response to infection.
28. True or False: Antibodies can opsonize pathogens, marking them for phagocytosis.
29. What is the role of cytokines in autoimmune diseases?
30. What is the primary function of interferons (IFNs)?
31. In terms of lifespan, how do neutrophils compare to macrophages?
32. What is the primary role of memory T cells?
33. True or False: Vaccines are known to directly cause autoimmune diseases.
34. Which of the following is NOT a function of TGF-β?
35. What is NOT a characteristic of innate immunity?
36. Fill in the blank: T cells recognize antigens presented by ___ molecules.
37. What is an example of a Type II hypersensitivity reaction?
38. IL-6 is primarily associated with which of the following effects?
39. What triggers the activation of natural killer (NK) cells?
40. What is clonal selection in the context of adaptive immunity?
41. Fill in the blank: Hashimoto's thyroiditis is characterized by an immune attack on the ________ gland.
42. What do growth factors primarily stimulate in the immune system?
43. How do macrophages enhance the immune response after phagocytosis?
44. List two functions of antibodies.
45. What is the primary effect of chronic stress on the immune system?
46. Fill in the blank: The main source of IL-6 is __________.
47. Fill in the blank: Cytokines play a role in __________ communication between immune cells.
48. True or False: All memory B cells are short-lived.
49. Which immune system disorder is characterized by the presence of anti-nuclear antibodies?
50. True or False: Cytokines can function only in autocrine signaling.
51. Which of the following cells are known for their role in allergic responses?
52. Cause → Effect: Exposure to an antigen triggers ___ .
53. Which of the following is a common treatment approach for autoimmune diseases?
54. What is the role of GM-CSF in the immune system?
55. What is the main function of phagocytes in the immune system?
56. What is the difference between active and passive immunity?
57. What characterizes anaphylaxis?
58. What effect do cytokines have on the blood-brain barrier?
59. True or False: Innate immunity has a memory component.
60. Which of the following describes the function of regulatory T cells?
61. Which immune response is characterized by an immediate allergic reaction?
62. Which of the following statements about cytokines is TRUE?
63. Which of the following cells is primarily involved in the defense against larger parasites like helminths?
64. Which of the following statements accurately describes the function of cytotoxic T cells?
Related Study Sets
Erregungsleitung saltatorisch und kontinuierlich fürs Abi
Abiturwissen: Synapsengifte und Drogen
Abi-Lernzettel: EPSP und IPSP Verrechnung
Abi-Lernzettel: Sehvorgang Fototransduktion Stäbchen
Neuronale Plastizität Lernen und Gedächtnis Zusammenfassung
Parkinson und Alzheimer Neurobiologie Lernzettel
Abitur Muskelkontraktion Prüfung
Ruhepotenzial Ionenverteilung Zusammenfassung
Create Your Own Study Set
Upload a PDF, paste your notes, or describe a topic – AI generates flashcards, quizzes and more in seconds.
