B1 Immune response

• What is an antigen?

  it is part of an organisms or substance that is recognised as foreign and stimulates an immune response
• What is cell mediated immunity?

  how the immune system response to antigens presented on w body cell to destroy pathogens
• What do plasma cells secrete?

  antibodies
• What do memory cells do?

  In the secondary response they differentiate into plasma cells, producing antibodies.
• What is humoral immunity?

  antibody-mediated immunity
• What do receptors have do in T cells?

  T cells have receptors that only response to one antigens
• What are some physical barriers?

  -Skin is a protective barrier

  -Eyelashes stop dust from coming in your eyes

  -Nose hairs traps bacteria from entering the nose.
• What are some chemical barriers

  -Salivary glands secret lysozymes which kills bacteria

  - Stomach secrets HCL denatures protein

  - Lungs goblet cells produce mucus which traps bacteria
• What are neutrophils?


  drawn to site of infection and carries out phagocytosis
• What are mast cells?

  Detects microorganisms and foreign substances and releases histamines
• What are B cells covered in?

  Proteins that are able to bind ti specific antigens
• What can T cells divide into?

  T killer cells and T memory cells
• What do T helper cells do?

  Binds to an antigen-presenting B cell and produces cytokines that stimulate B cell to divide and become capable of producing antibodies.
• 6 stages of phagocytosis

  1. phagocytes are attracted towards pathogens as they produce chemicals. phagocytes recognise the non human protein on the pathogen

  2. phagocytes engulfs the pathogen ans enclose it in a vacuole

  3.enzymes from the lysosome digest and destroy the pathogen

  4. dead neutrophils and dead pathogen dont reenter the blood
• What is natural passive immunity?

  babies gain immunity through antibodies received from the mother through the placenta and from breast milk.
• What is artificial passive immunity?

  immunity gained after injection with antiserum containing antibodies produced by another person or animal this provides immunity to a specific disease