Immune system II Flashcards
What are pathogens?
Pathogens are outside invaders. These include germs like bacteria, parasite viruses, and fungi, and toxins (chemicals made by microbes/microorganisms).
Each pathogen is made up of several subparts, usually unique to that specific pathogen and the disease it causes.
The subpart of a pathogen that causes the formation of antibodies is called an antigen.
What are microbes?
Microbes are organisms that are too small to be seen without using a microscope, so they include things like bacteria, archaea (no nucleus or any other organelles), and
single cell eukaryotes (cells that have a nucleus).
Sometimes we call viruses microbes too (but they are not living).
Some microbes make us sick; others are important for our health.
Antigens
on the surface of the invader. Act as a “label” that the immune system
uses to recognize what is foreign.
Chemotaxis
Chemotaxis (from chemo + taxis) is the movement of an organism or entity in response to a chemical.
In other words, the migration of cells toward attractant chemicals or away from repellents.
How does the immune system work?
1) When the body senses foreign substances, the immune system works to recognize and get rid of them.
2) B lymphocytes are triggered to make antibodies (also called immunoglobulins).
3)These proteins lock onto specific antigens on the surface of pathogens.
4) After they’re made, antibodies usually stay in our bodies in case we have to fight the same germ again.
That’s why someone who gets sick with a disease, like chickenpox, usually won’t get sick from it again.
Antibodies
Antibodies are proteins produced by B cells following the detection of a
substance recognized as foreign (antigen).
Although antibodies can recognize an antigen and lock onto it, they can’t destroy the pathogen
without help.
Antibodies can also neutralize toxins (poisonous or damaging substances) produced by different
organisms.
What is the role of a T cell
They destroy pathogens tagged by antibodies or cells that are infected or somehow changed. (Some
T cells are called “killer T cells.”)
T cells also help signal other cells (like phagocytes) to do their jobs.
Vaccines
Immune memory is the basis behind vaccines
An immunization introduces the body to an antigen.
It triggers the body to make antibodies that will protect the person from future attack
by the germ.
Immunocompromised individuals (e.g., the elderly, newborns, etc.) are vulnerable and may be unable to build up a strong enough immune response on their own (without a
vaccine).
Vaccines safely expose our immune system to antigens.
How do vaccines work?
Vaccines prepare the body’s immune system by mimicking infection.
They trigger the body’s adaptive immune system without exposing us to the full-strength disease
They teach the body to recognize and attack the pathogens when a real
infection happens
What are the two types of vaccines
Live attenuated and Inactive
The weaker and inactive nature of the vaccines ensures that the pathogens don’t develop into the
full-blown disease.
- Live attenuated vaccines
Made of a weaker version of the pathogen
Difficult to make
Strong, so people with weaker immune systems cannot have them
- Inactive vaccines
The pathogens have been killed
Don’t create long-lasting immunity (booster shots)
What are autoimmune diseases?
Autoimmune disease happens when the body’s natural defense system can’t tell the difference between your own cells and foreign cells, causing the body to mistakenly
attack normal cells.
There are more than 80 types of autoimmune diseases that affect a wide range of body
parts.
Autoimmune diseases can affect anyone, but women are at greater risk.
These diseases also share common symptoms: fatigue, dizziness, and low-grade fever.
Which of the following is an autoimmune disease?
A. Type 1 diabetes
B. Rheumatoid arthritis
C. Psoriasis
D. All of the above
D
If you have an autoimmune disease, what happens with the immune system?
A. Your immune cells die
B. Antibodies from your immune system mistakenly attack tissues in the body
C. Your immune system makes too many immune cells
D. None of the above
B