Immune System Trivia Quiz Questions
What is the immune system?
A: The immune system is a defense system comprising biological structures
and processes within an organism that protects against
disease.
To function properly, an immune system must detect a
wide variety of agents, known as what?
A: Pathogens, from viruses to parasitic worms.
In many species, what are the two major subsystems of
the immune system?
A: The innate immune system and the adaptive immune system.
In humans, the blood brain barrier, blood cerebrospinal
fluid barrier, and similar fluid brain barriers separate the peripheral
immune system from the what?
A: The neuroimmune system, which protects the brain.
Pathogens can rapidly evolve and adapt, and thereby do
what?
A: Avoid detection and neutralization by the immune system.
Multiple defense mechanisms have also evolved to
recognize and neutralize what?
A: Pathogens.
Even simple unicellular organisms such as
bacteria
possess a rudimentary immune system in the form of enzymes that protect
against what?
A: Bacteriophage infections.
Other basic immune mechanisms evolved in ancient
eukaryotes and remain in their modern descendants, such as what?
A: Plants and invertebrates.
Jawed vertebrates, including humans, have even more
sophisticated defense mechanisms, including the ability to do what?
A: Adapt over time to recognize specific pathogens more efficiently.
Adaptive (or acquired) immunity creates immunological
memory after an initial response to a specific pathogen, leading to what?
A: An enhanced response to subsequent encounters with that same pathogen.
This process of acquired immunity is the basis of what
preventative measure?
A: Vaccination.
Disorders of the immune system can result in what?
A: Autoimmune diseases, inflammatory diseases and cancer.
Immunodeficiency occurs when the immune system is less
active than normal, resulting in what?
A: Recurring and life-threatening infections.
In humans, immunodeficiency can either be the result of
a genetic disease or acquired conditions such what?
A: Such as HIV/AIDS, or the use of immunosuppressive medication.
Autoimmunity results from a hyperactive immune system
attacking what?
A: Normal tissues as if they were foreign organisms.
The immune system protects organisms from infection
with layered defenses of increasing what?
A: Specificity.
In simple terms, physical barriers prevent pathogens
such as bacteria and viruses from doing what?
A: Entering the organism.
If a pathogen breaches these barriers, the innate
immune system provides what?
A: An immediate, but non-specific response.
Where are innate immune systems found?
A: In all plants and animals.
If pathogens successfully evade the innate response,
vertebrates possess a second layer of protection called what?
A: The adaptive immune system, which is activated by the innate response.
Here, the immune system adapts its response during an
infection to improve what?
A: To improve its recognition of the pathogen.
This improved response is then retained after the
pathogen has been eliminated, in the form of a what?
A: An immunological memory.
This allows the adaptive immune system to mount faster
and stronger attacks each time what happens?
A: This pathogen is encountered.
Both innate and adaptive immunity depend on the ability
of the immune system to distinguish between what?
A: Self and non-self molecules.
In immunology what are self molecules?
A: Those components of an organism's body that can be distinguished from
foreign substances by the immune system.
Newborn infants have no prior exposure to microbes and
are particularly vulnerable to what?
A: Infection.
Several layers of passive protection are provided by
whom?
A: By the mother.
Breast milk or colostrum also contains antibodies that
are transferred to the gut of the infant and protect against what?
A: Bacterial infections until the newborn can synthesize its own antibodies.
This is passive immunity because the fetus does not do
what?
A: It does not actually make any memory cells or antibodies?it only borrows
them.
This passive immunity is usually short-term, lasting
for how long?
A: From a few days up to several months.
In medicine, protective passive immunity can also be
transferred artificially from one individual to another via what?
A: Antibody-rich serum.
Microorganisms or toxins that successfully enter an
organism encounter the cells and mechanisms of what?
A: The innate immune system.
The innate response is usually triggered when microbes
are identified by what?
A: Pattern recognition receptors.
Innate immune defenses are non-specific, meaning what?
A: Meaning that these systems respond to pathogens in a generic way.
This system does not confer what against a pathogen?
A: Long-lasting immunity
What is the dominant system of host defense in most
organisms?
A: The innate immune system.
Cells in the innate immune system use pattern
recognition receptors (PRRs) to recognize molecular structures that are
produced by what?
A: Microbial pathogens.
Several barriers protect organisms from infection,
including mechanical, chemical, and what?
A: Biological barriers.
The waxy cuticle of most leaves, the exoskeleton of
insects, the shells and membranes of externally deposited eggs, and
skin are
examples of what?
A: Mechanical barriers that are the first line of defense against infection.
However, as organisms cannot be completely sealed from
their environments, other systems act to protect body openings such as what?
A: The lungs, intestines, and the genitourinary tract.
In the lungs, coughing and sneezing does what?
A: It mechanically ejects pathogens and other irritants from the respiratory
tract.
The flushing action of tears and urine also
mechanically expels pathogens, while mucus secreted by the respiratory and
gastrointestinal tract serves to do what?
A: To trap and entangle microorganisms.
In the stomach, what serves as a powerful chemical
defense against ingested pathogens?
A: Gastric acid.
Leukocytes (white blood cells) act like independent,
single-celled organisms and are the second arm of what?
A: The innate immune system.
Phagocytosis is an important feature of cellular innate
immunity performed by cells called phagocytes that do what?
A: They engulf, or eat, pathogens or particles.
Neutrophils and macrophages are phagocytes that travel
where, in pursuit of invading pathogens?
A: Throughout the body.