week 15 Immune system

• What is the primary function of the immune system?


  To protect the body from foreign organisms and pathogens through various defence mechanisms, including barriers, innate and adaptive immunity, tolerance, and the lymphatic system.
• What are the first-line barriers of the immune system?


  Skin and mucous membranes, which trap and expel pathogens
• What are chemical barriers in the immune system, and what do they do?


  Sebum, sweat, stomach acid, and natural flora prevent pathogen growth.
• What are the two main types of immunity?

  Innate immunity (non-specific and immediate) and adaptive immunity (specific, with memory)
• What is the role of the lymphatic system in immunity?


  It produces lymphocytes, transports dietary lipids, and drains excess interstitial fluid, aiding in immune defence
• What immune cells are categorized as granulocytes?

  Neutrophils, eosinophils, and basophils, which are involved in inflammation and allergic responses.
• What is the role of agranulocytes like monocytes and dendritic cells?


  They perform phagocytosis and present antigens to other immune cells.
• How do B cells and plasma cells function in immunity?

  B cells differentiate into plasma cells, which produce antibodies (immunoglobulins) in response to antigens
• What are the types of T cells, and what are their roles?


  Helper T cells (coordinate immune response), suppressor T cells (regulate tolerance), and cytotoxic T cells (kill infected cells).
• What are Natural Killer (NK) cells, and what is their function?


  NK cells are lymphocytes that quickly respond to infections and cancerous cells, often activated by cytokines.
• Name five types of immunoglobulins and their general roles.


  IgG, IgM, IgA, IgE, and IgD, each playing roles from providing long-term immunity to mediating allergic reactions.
• List four types of antimicrobial substances and their functions.


  1. Interferons: Inhibit viral replication.
  2. Complement System: Promotes cell lysis, inflammation, and phagocytosis.
  3. Iron-binding Proteins: Restrict iron to inhibit bacterial growth.
  4. Antimicrobial Proteins: Kill microbes and attract immune cells.
• What distinguishes innate immune response from adaptive immune response?


  Innate immunity is non-specific and rapid, while adaptive immunity is specific and develops memory cells for faster future responses.
• What are the three stages of inflammation?

  Vasodilation, phagocyte emigration, and tissue repair, marked by redness, swelling, heat, pain, and loss of function
• Define autoimmune disorders and give an example.


  Disorders where the immune system attacks self-tissues; an example is rheumatoid arthritis.
• What are immunodeficiencies, and provide an example.


  Conditions with reduced immune defense, such as HIV/AIDS.
• What are hypersensitivities, and how are they categorized?


  Overactive immune responses to harmless substances, categorized into four types (e.g., Type I involves allergies).
• Name three common lymphatic diseases.

  Lymphoedema (swelling from node blockage), lymphadenopathy (node enlargement from infection or cancer), and lymphoma (cancer involving lymph nodes).