Cell Recognition and the Immune System Flashcards
How do specific defence mechanisms differ from non-specific defence mechanisms?
Specific:
-slower
-produce unique response for each type of pathogen
-provide long term immunity
Where in the body do T cells mature?
Thymus gland
Where in the body do B cells mature?
Bone marrow
Which part of the specific immune response involves T lymphocytes?
Cellular response
Which part of the specific immune response involves B lymphocytes?
Humoral response
What is the function of helper T cells?
-bind to antigen-presenting cells
-form memory cells
-stimulate B cells or phagocytes
-activate cytotoxic T cells
What is the role of cytotoxic T cells?
Kill infected or abnormal cells
What is the cellular response?
Specific immune response
that occurs when T cells respond to antigens presented on body cells
What are the functions of cloned T cells?
- Develop into memory cells
- Stimulate phagocytosis
- Stimulate division of B cells
- Activate cytotoxic T cells
What are antigen-presenting cells?
Cells (usually phagocytes)
that display a pathogen’s antigens in their cell surface
Describe the steps involved in the cellular response to pathogens
- Phagocytes engulf pathogens and display their antigens on the cell surface
- Helper T cells with complementary receptors bind to these antigens
- This activates the T cell to divide by mitosis to form genetically identical clones
- These clones can carry out different functions
What is the humoral response?
Specific defence mechanism
involving the production of antibodies to destroy pathogens
What are B lymphocytes?
involved in the humoral response
are covered in antibodies
Which process activates the division of B cells?
Helper T cells bind to antigen-presenting B cells to activate B cell division
What do plasma cells do?
Produce and secrete antibodies against a specific antigen
How many polypeptide chains do antibodies contain?
4
The polypeptide chains within an antibody are held by _____ bridges
Disulfide
Which region of the antibody binds to antigens?
Variable region
What is the name of the region that is the same in all antibodies?
Constant region
What is the name of the structure formed when an antibody and antigen bind together?
Antigen-antibody complex
Why are antibodies specific to certain antigens
Antibodies have unique binding sites in their variable regions that are complementary to specific antigens
What is made easier by agglutination of pathogens?
Phagocytosis
Toxins can be neutralised by ____.
Antibodies
What are monoclonal antibodies?
Antibodies produced by a cloned cell that can bind to one specific antigen
True or false?
Monoclonal antibodies are identical to one another
True
Monoclonal antibodies are produced from a single clone of cells and so are identical
Give 3 uses of monoclonal antibodies
- Diagnose disease or cancer
- Target medication to certain cells
- Test for pregnancy
How many antibodies does the indirect ELISA test involve?
2
After adding antibodies to the well, it must be washed to remove any ______ antibodies.
Unbound
In the indirect ELISA test, which antibody has an enzyme attached?
the second antibody
