OVERVIEW OF THE IMMUNE SYSTEM
THE GOOD BAD AND UGLY OF THE IMMUNE SYSTEM
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Kristen has not developed antibodies to chickenpox.
|
|
|
Kristen has developed a vaccination against chickenpox.
|
|
|
Kristen’s body no longer contains cells that can be damaged by chicken pox.
|
|
|
Kristen’s body has memory cells that will produce antibodies to fight chickenpox.
|
Detailed explanation-1: -Q. When Kristen was five, she became sick with chickenpox & then recovered. Why is Kristen unlikely to get chickenpox a second time? Kristen has not developed antibodies to chickenpox.
Detailed explanation-2: -Most people who have had chickenpox will be immune to the disease for the rest of their lives. However, the virus remains inactive in nerve tissue and may reactivate later in life causing shingles. Very rarely, a second case of chickenpox does happen.
Detailed explanation-3: -It is essential to understand that memory B cells do not produce antibodies-i.e., they do not protect. Their participation to vaccine efficacy requires an antigen-driven proliferation and differentiation process.
Detailed explanation-4: -When a pathogen is contacted again, memory cells guarantee that a receptor specific for a particular epitope is present. There are more lymphocytes with this specificity than in a host that has never encountered the antigen.
Detailed explanation-5: -Immunological memory is a unique property of the immune system as it can “store” information about a stimulus and can mount an effective response when the stimulus is encountered again. This response – a secondary immune response – is quicker and stronger than the primary response.
Detailed explanation-6: -The immune system keeps a record of every microbe it has ever defeated, in types of white blood cells (B-lymphocytes and T-lymphocytes) known as memory cells. This means it can recognise and destroy the microbe quickly if it enters the body again, before it can multiply and make you feel sick.