Download Evading the Innate Immune System

Organismal Systems: A Summary of Biological Systems
Chemical Defense Systems
 Animal and plants have ________________________ to fight against foreign
invaders.
 The ________________________is one of the best studied of these systems.
 Vertebrate Immune System
 The ________________________ recognizes foreign invaders such as
viruses, bacteria, fungi, parasites and other _____________________.
 Two major modes of attack have evolved:
 ____________________________________________________
 ____________________________________________________
 3 main lines of defense:
 ___________: Physical barriers, chemical barriers, and
mechanical barriers.
 ___________: Phagocytes, complement, inflammation, fever
 ___________: Cell-mediated and humoral
 __________________________: is present at birth (______________
___________________________), is ________________ and consists
of ____________________ plus _______________________________
 __________________________: develops ______________________
______________ and involves a very ___________________________
to pathogens.
 A Microbe Invading the Body will Encounter the Following Defenses:
st
 1 Line of Defense:
 _______________________:
 ____________: physical barrier prevents entry into body: low pH
prevents microbial growth
 ___________________________ of respiratory, urinary, and
reproductive tracts: traps microbes, low pH of body fluids is
hostile to microbes
nd
 2 Line of Defense:
 White blood cells are the key players in a series of increasingly specific
attacks against invading microbes.
 _________________________________: engulf a pathogen in the
body and trap it within a vacuole. The vacuole then fuses with a
lysosome to destroy the microbe (phagocytosis). Many cells are
involved in this “________________________”
 The Generalized Attack
 _________________________________ of the generalized attack:
 ___________________: “eat” pathogens and send out distress signals.
 ___________________: arise from monocytes. They are the “big
eaters”. They circulate through the lymph system looking for any
foreign invader. Some reside permanently in the spleen and lymph
nodes, lying in wait for microbes.
 ____________________: release destructive enzymes to attack large
invaders like parasitic worms. Also involved in the inflammatory
response.
 ____________________: contain histamines that are released during
the inflammatory response.
 ____________________: arise from monocytes. They stimulate the
development of acquired immunity.
nd
 The remaining components of the 2 line of defense __________________
______________________.
 ________________ and _____________ attack microbes directly or
_________________________________.
 Example: ________________________ provide innate defense
against _____________ and help to activate microphages.
 About 30 proteins make up the _________________________, which
causes __________ of invading cells and helps trigger inflammation
 Inflammatory Responses
 Following an injury, __________________ release
_________________, which promotes changes in blood vessels;
this is part of the ___________________________
 These changes _________________________________ and allow
more _____________ and _________________________ to enter
tissues.
 __________ (a fluid rich in white blood cells, dead microbes, and
cell debris) accumulates at the site of inflammation.
 Symptoms of inflammation include ________________________
_____________________.
 Inflammation can be either _____________________ (throughout
the body)
 ___________ is a systemic inflammatory response triggered by
___________________ released by macrophages, and toxins from
pathogens.
 ________________________ is a life-threatening condition
caused by an overwhelming inflammatory response.
 Natural Killer Cells
 The last component of the innate immune system are the
__________________________________
 All cells in the body (except red blood cells) have a
____________________________________ on their surface.
 Cancerous or infected cells _____________________________
 ___________________________ attack these damaged cells,
inhibiting further spread of the virus or cancer.
 Evading the Innate Immune System
 Some pathogens evade the innate immune attack by
_____________________________________________________
_____________________________________________________
 Example: ______________________—these bacterium are
resistant to the enzymes inside the lysosomes. Thus, they can
hide inside white blood cells without being digested. This disease
kills more than a million people per year.
 Acquired Immunity
rd
 The 3 Line of Defense:
 White blood cells called ______________________ recognize and
respond to ________________ (foreign molecules).
 Lymphocytes that mature in the ______________ above the heart are
called _____________, and those that mature in _________________
are called ______________.
 These are the cells involved in the __________________________
 Lymphocytes contribute to _______________________________, an
enhanced response to a foreign molecule encountered previously. This
is what allows us to develop lifetime immunity to diseases like
chickenpox.
 The specialized attack usually occurs after being ___________________
___________________________________________________
 __________________ are secreted by ___________________________
to recruit and activate lymphocytes.
 The three stars of this more specialized attack are the
_______________ ________________________________________
 ___________ mature into __________________ that generate
highly specific ________________ capable of lasting immunity.
 ________________ play a central role in ________________ the
attack
 ________________, once activated, destroy
_____________________.
 B cells and T cells have
___________________________________________
___________________________.
 Each individual lymphocyte is
______________________________________
______________________.
 Antigen Recognition by Lymphocytes
 An ______________ is any foreign molecule to which a ____________
_________________
 A single B cell or T cell has about 100,000 identical
__________________________.
A typical immune response to a virus is seen in the following diagram.
 From the diagram, we can see that there are two types of specific responses:
____________________________________________ and _______________
____________________________________________
 The ___________________ can initiate both responses.
 Antigen Recognition
 Recognition of the antigen begins when a ______________________
(as seen in the diagram), a ____________, or a ___________________
presents the foreign antigen by engulfing the invader, digesting the
particle, and then ___________________________________________
 _____________________ (major histocompatibility complex) are used
to present the antigens
 __________________ then __________ to the presented antigen and
_______________ the production of more T and B cells by releasing
_________________.
 This initiates both the ________________________________________.
 The Humoral Response
 In the humoral response, activated B cells give rise to ______________,
which secrete ______________ or _____________________________
specific to the antigen presented.
 _____________________ also form during the humoral response and
persist long after the initial infection ends.
 The Role of Antibodies
 By binding to a pathogen, antibodies can ________________ the
pathogen so that it can no longer infect a host cell.
 By binding to a pathogen, antibodies can _______ them so that they are
more easily and quickly identified and __________________________.
 Antibodies, together with proteins of the complement system generate
a ______________________________ and _______________.
 The Cell-Mediated Response
 In the ______________________________, cytotoxic T- cells target
_____________________________ which B-cells cannot recognize.
 ____________________________________.
 ______________________________________________ detect and
destroy altered or infected body cells.
 _____________________ are also generated.
 Primary and Secondary Responses
 The first exposure to a specific antigen represents the ______________
______________________.
 During this time, __________________ are generated, _____________
are activated, _____________ and ____________________________
are produced.
 In the _______________________________, memory cells facilitate a
faster, more efficient response.
 Lymphocyte Development
 The __________________________ has three important properties
 ________________________—our cells have an amazing ability
to rearrange genes to generate over 1 million different B cells and
10 million different T cells.
 _______________________________________—as lymphocytes
mature, any that exhibit receptors specific for the body’s own
molecules are destroyed by apoptosis.
 __________________________—there is an increase in cell
number and behavior triggered by the binding of antigen that
allows the immune system to “remember attackers”
 Active and Passive Immunity
 ______________________ develops naturally in __________________
____________________.
 It can also develop following _____________________, also called
___________________.
 _______________________ provides immediate, __________________
_________________
 It is conferred naturally when _____________________________
from mother to fetus or from _____________________________.
 It can be conferred artificially by ___________________________
into a non-immune person
 Immune Rejection
 _________________________ from one person to another can be
attacked by immune defenses
 This complicates ____________________ and ____________________.
 _________________ are different from person to person and this
difference stimulates most _______________________.
 Successful transplants try to match MHC tissue types and utilize
________________________________.
 Blood Groups
 Antigens on red blood cells determine whether a person has blood type
A (A antigen), B (B antigen), AB (both A and B antigens), or O (neither
antigen)
 _________________________________________________________
 Transfusion with incompatible blood leads to ____________________
_____________________
 Recipient-donor combinations _______________________ or safe
 Disruptions of Immune System Function
 ______________: exaggerated responses to antigens called allergens
 _________________________: an acute, allergic, life-threatening
reaction that can occur within seconds of allergen exposure
 _________________________: the immune system loses tolerance for
self and turns against certain molecules of the body.
 Examples: ____________________________________________.
 Acquired Immunodeficiency Syndrome (AIDS):
 Caused by _____________________________________________
 Infects ___________________
 Impairs both the _____________ and the ____________________
_________________.
 HIV eludes the immune system because of ___________________
and an _______________________________________________.
 People with AIDS are highly susceptible to ___________________
______________ and _____________ that take advantage of an
immune system in collapse.
 _____________: The frequency of certain cancers _________________
________________________________.
 Two suggested explanations are:
 Immune system ____________________________________
 ___________________________ increases the risk of
cancer.
Eliminating Wastes and Obtaining Nutrients
 Organisms have a _______________________________ for obtaining
nutrients and eliminating wastes.
 These mechanisms all contribute to ____________________________
in living things.
 Removal of Nitrogen Waste
 All animals must _________________________________________,
their body fluids.
 Examples:
 ____________: have _________________________,: nitrogen
waste diffuses out across the body wall.
 ______________: have a ___________________________ that
delivers nitrogen waste in the form of ammonia to a special pore
in the body surface.
 ____________: convert ___________________________ to
reduce water loss.
 _______________: have a ___________________ with two
kidneys that filters the blood and adjusts its solute concentration.
 In most organisms, circulation and gas exchange play a critical role in
_______________________ and assisting in the __________________.
 Circulation and Gas Exchange
 In most animals, the _________________________________________
________________________.
 In ___________________________, cells can exchange materials
______________ with the surrounding medium
 In other animals, _______________________________________
_____________________________
 Most complex animals have ______________________________
__________________________.
 Gastrovascular Cavities
 Simple animals, such as ____________________________, have a body
wall that is only two cells thick and encloses a ____________________.
 This cavity functions in both ______________________________ of
substances throughout the body.
 Open and Closed Circulatory Systems
 More complex animals have either _____________________________.
 Both systems have three basic components:
 _______________________________ (blood or hemolymph)
 ___________________________ (blood vessels)
 ___________________________ (the heart)
 In insects, other arthropods, and most molluscs, ___________________
_____________________ in an ________________________________
 There is __________________________________________, and
this general body fluid is more correctly called _______________.
 Vertebrate animals have a _____________________________ in which
blood is ___________________ and is distinct from the interstitial fluid.
 Closed systems are _____________________.
 Organization of Vertebrate Circulatory Systems
 The _______________________ is an example of a ________________
_________________ that supports the idea of ____________________.
 It _____________________________________ and _______________
______________________________________.
 All vertebrate circulatory systems are closed (_____________________)
 However, there are _______________ between fish, amphibians, and
mammals that have evolved over millions of years (________________)
 _________: heart has _________________ (one atrium and one
ventricle) and blood flows through _______________. It picks up
oxygen in the capillary beds of the gills and delivers it to capillary
beds in all body tissue.
 __________________: heart has _______________________
(two atria and one ventricle) and blood flows along ____________
_____________________. Oxygenated blood and oxygen-poor
blood mix a bit in the ventricle.
 _________________________: heart has __________________
(two atria and two ventricles) and blood flows through _________
_____________________. One goes to the lungs and back and
the second goes from the heart to all body tissues and back. This
keeps _________________________________________________
 Mammalian Circulation
 Mammals provide an excellent example of double circulation.
 Blood begins its flow with the ____________________ pumping blood
________________
 In the lungs, the blood ___________ and _________________
 Oxygen-rich blood from the lungs enters the heart at the ___________
___________ and is pumped through the ____________ to the body
tissues by the ____________________
 The aorta provides blood to the heart through the _________________
 Blood returns to the heart through the _________________________
(blood from head, neck, and forelimbs) and ______________________
(blood from trunk and hind limbs)
 The superior vena cava and inferior vena cava flow into the right atrium
 ________________________________ of blood in the heart.
 Two ___________________________ valves separate each atrium
and ventricle.
 The ___________________________ control blood flow to the
aorta and the pulmonary artery.
 The Mammalian Heart
 A closer look at the ___________________________ provides a better
understanding of double circulation.
 The contraction, or pumping, phase is called _________________.
 The relaxation, or filling, phase is called __________________
 Vessels of the Circulatory System
 Three main blood vessels are: arteries, veins and capillaries
 ______________: carry _____________ blood ___________ from
heart; branch into _______________ and then to capillaries
 _______________: form a network known as ________________;
provide the site for ____________________________________
the blood and interstitial fluid.
 __________: carry ________________ blood _________ to heart;
capillaries converge into ____________ and then into __________
 The critical exchange of substances between the blood and interstitial
fluid takes place across the thin ________________________________
 The difference between ______________________________________
drives fluids ______ of capillaries at the ___________________ and
_________ capillaries at the __________________
 The __________________________ returns fluid that ______________
___________________
 This system __________________________
 Fluid, called _____________, reenters the circulation directly at
the venous end of the capillary bed and indirectly through the
lymphatic system
 The lymphatic system ________________________________
 _________________ are organs that ________________ and play
an important role in the body’s defense
 _____________ is swelling caused by _______________________
________________
 Gas Exchange
 ___________________ supplies oxygen for cellular respiration and
disposes of carbon dioxide.
 Gases like _____ and _______, ________________________________
in the lungs and other organs from where their ___________________
___________________________________
 Respiratory Media
 Animals can use _________________ as a source of oxygen.
 Obtaining oxygen from water actually _________________________
than air breathing since there is ________________________________
than in air.
 Gas exchange takes place by ____________ across either the ________,
_______________________________.
 All respiratory organs ______________________________________.
 Gills
 Gills are ____________________ of the body
 Fish move water over their gills and use a ________________________
___________, where blood flows in the _________________________
to water passing over the gills; ________________________________
___________________________.
 Tracheal Systems
 The _____________________ of insects consists of tiny branching
tubes that penetrate the body.
 These tubes supply O2 _________________________.
 The __________________________________________________.
 Larger insects ___________________ their tracheal system to meet O2
demands.
 Lungs
 Lungs are infolding of the body surface.
 The ________________________ (open or closed) transports gases
between the lungs and the rest of the body.
 Air inhaled through the nostrils passes through the pharynx via the
_____________________________________________________.
 How animals breath
 An amphibian ventilates its lungs by ___________________________,
which forces air down the trachea.
 Mammals ventilate their lungs by ______________________________,
which pulls air into the lungs.
 In either case, the gas exchange must be coordinated with circulation.
 Coordination of Circulation and Gas Exchange
 ____________________ in the lungs has a _______________________
__________________________________________________________
 In the alveoli, _______________ the blood and ___________________
 In tissue capillaries, __________________________________________
____________________________________________________
 Respiratory Pigments
 _______________________, proteins that transport oxygen, greatly
increase the amount of oxygen that blood can carry
 Arthropods and many molluscs have ________________ with
_____________ as the oxygen-binding component
 Most vertebrates and some invertebrates use __________________
contained within erythrocytes
 Carbon Dioxide Transport
 Hemoglobin also helps ______________________________________
 ________ from respiring cells diffuses into the blood and ___________
_______________ either in blood plasma, _______________________,
–
or as ______________________________ (HCO )
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