Download Lymphatic System Guided Notes

Lymphatic System Guided Notes
Name:________________________
Do Now
You drink a glass of water. What path does it take through the body?
Lymphatic System Function
The lymphatic system consists of two main parts, each with different functions:
1.
________________________ collect interstitial fluid and return it to the blood vessels
2. _________________________house immune cells and help protect the body from disease
Lymphatic capillaries

Lymphatic capillaries collect interstitial fluid and dissolved particles, including proteins, cell debris, and
pathogens

Surround blood capillaries in loose connective tissue

_________________________ (have a true start)

__________________________ ensure fluid only goes in one direction – towards heart.
Lymphatic capillaries are MUCH more permeable
than blood capillaries. Large particles, including
pathogens and cancer cells, cannot directly get into
blood capillaries but they easily enter lymphatic
capillaries
Other lymphatic vessels
 Lymphatic capillaries join together to form lymphatic vessels.
 Lymphatic vessels pass through multiple lymph nodes for
cleansing
 Lymphatic vessels empty into the subclavian veins
What makes lymph flow?
 ________________________________________________
________________________________________________
 Higher pressure of interstitial fluid than of lymph in
capillaries starts flow
 Respiratory and skeletal muscle pumps help maintain flow in lymph vessels
 Largest lymph vessels have smooth muscle walls that contract rhythmically to push lymph along

__________________________________________________________________________________________
 Minivalves in capillaries
 ‘true’ valves in large lymph vessels
Compare and contrast blood vessels and lymphatic vessels in terms of structure and function.
Lymph Nodes
 ___________________________________________________ (phagocytes and lymphocytes)
 Filter lymph, breaking down cell debris and destroying pathogens and cancer cells
There are thousands of lymph nodes scattered throughout the body.
Large clusters of lymph nodes occur in cervical (neck), axillary (arm pit), and inguinal (groin) area.
Other Lymphoid Organs
 House immune cells, but do not filter lymph
 __________________: trap and remove pathogens that enter throat
 __________________: produces hormones and develops T-lymphocytes
 __________________: filters blood, destroys old erythrocytes
 __________________: destroy pathogens in intestines
Non-specific Body Defenses
Do Now
Name some structures or processes that protect us from disease.
The body has two systems that fight disease
1. ________________________________________ system
 Protects body from ____________________foreign substances
1. ________________________________________system (aka _________________ system)
 Protects body from __________________ foreign substances
Surface Barriers
_________________ and _________________________ prevent pathogens from entering body
 _________________________________________________________________
 ____________________________ in skin, vagina, and stomach
___________________________________________________________________
 ___________________ in respiratory and digestive tracts ________________________
 ___________________________ contain an enzyme – lysozyme – that
______________________________________________.
Cellular Defenses
The body has specialized cells that destroy foreign material
 ______________________________ (macrophages & neutrophils) –
____________________________________________________________________________, such as bacteria
and viruses
 ______________________________________ (a type of lymphocyte) –
____________________________________________________________________________ that destroy cell
membranes.
Inflammation
Inflammation occurs when an area that is damaged or infected becomes
____________________________________________________________________________________.
Occurs when damaged cells release chemicals that ________________________________________,
________________________________________________________, and ______________________________.
How does it protect the body?
 ___________________________________________ to nearby tissue
 helps rid body of pathogens and dead cells
 Helps speed healing
Fever
Fever is when the body’s temperature becomes elevated due to infection
Occurs when white blood cells release chemicals that reset the body’s thermostat
How does it protect the body?
 ______________________________________________ by causing the liver & spleen to take up nutrients
 _______________________________________________ to speed the healing process
Why do we get the chills when we have a fever?
Immune System Guided Notes
Do Now
What is the difference between the non-specific and specific defense system?
Which one is activated by vaccines?
The specific defense system
The specific defense system (aka immune system) recognizes and attacks specific pathogens.
The immune system has 3 important characteristics:
» Antigen-specific
» Systemic
» Has memory
What are antigens?
What does systemic mean?
Cells (and chemicals) of the immune system
»
_________________________________
•
_________________________________ function in non-specific defense* to kill virus infected or
cancerous body cells
•
________________________________ mature in bone marrow. They become activated by binding to
specific antigens then divide to form:
•
•
_______________________ which release antibodies
•
_______________________ which ‘remember’ specific antigens
_______________________ mature in the thymus. They become activated by binding to specific
antigens then divide to form:
•
________________________________________ kill virus infected or cancerous body cells
•
_______________________________________ stimulate the production of immune cells and
release chemicals which help destroy pathogens
•
_______________________________________ stop activity of immune cells after infection is
over
•
_______________________________________ ‘remember’ specific antigens
What do the B and T refer to?
Which cell has a similar function to NK cells? How are these two cells different?
Which cells directly attack pathogens?
»
_______________________________________________
•
»
Play a role in non-specific AND specific defense system
Antibodies
•
______________________________________________________________ (non-specific
system)
•
Act as ________________________________ (specific system) by displaying fragments of these
particles on their surface and activating T lymphocytes.
»
•
Proteins produced by plasma cells (B cells) that bind to specific antigens
•
Binding of antibodies to pathogen causes their destruction / inactivation in one of a few ways
•
_____________________________________: Encourages other chemicals (complements) to
punch holes in the surface of the pathogen, destroying it.
•
_____________________________________: Binding prevents viruses or toxins from entering
healthy body cells
•
____________________________________: clumping of antibody-bound particles, which
makes them unable to enter healthy cells and more likely to be eaten by phagocytes
•
______________________________________ – the presence of antibodies ‘flags’ a pathogen,
increasing the chance that it will be eaten by a phagocyte.
Other important chemicals
•
______________________________ – proteins that in blood that bind to pathogens; activity increased
by presence of antibodies
•
________________________________ – proteins that bind to virus-infected cells and reduce the ability
of viruses to multiply; also work with T cells to increase recognition of virus infected or cancerous cells.
•
________________________ and _____________________ – cause inflammatory response
•
______________________ and ______________________ – released by T cells, increase immune
response and directly destroy pathogens
Circle the chemicals you need to know!
Two branches of the Immune system
There are two branches of the immune system:
»
The ________________________________________________ which involves the production of
_________________________ that fight ___________________________________________ (pathogens
including viruses and bacteria that are among our cells, but not inside them).
»
___________________________________________________ which involves the activation of
________________________________ that destroy _________________________________ and
___________________________________.
The story of the lucky lymphocyte
The body naturally produces a HUGE array of B- and T- lymphocytes, with widely diverging receptors. Each receptor is
capable of binding with only one type of antigen. These mature, but inactive, lymphocytes take up residence in
lymphatic organs and wait to meet their antigen.
Most never will.
The lucky few lymphocytes that do bind to their antigen will undergo clonal selection so that they, and their multitude of
offspring, can fulfill their destiny by participating in the humoral or cell-mediated immune response.
Humoral Immune Response
1. B-lymphocytes bind to specific, free-floating
antigens and become activated.
2. The activated B-lymphocyte divides many
many times, forming identical clones, also
capable of binding to the antigen.
3. Most of these clones will become plasma
cells that specialize in producing antibodies
that bind only with that specific antigen.
4. A few will become long-lived memory cells
that will persist for years, waiting in case the
same antigen is encountered again.
Primary vs. Secondary Humoral Immune Response
»
The primary humoral immune response occurs the first time the immune system encounters a specific antigen.
Why?
»
The secondary humoral immune response occurs any time after the immune system first defeats an antigen.
This response is much faster and produces more antibodies.
Why?
How does this graph explain the function of vaccines?
Why are booster vaccinations necessary?
Types of acquired immunity
The least common method is artificial passive immunity. Used for exposures / disorders that are likely to be fatal before
the body can mount its own immune defense.
Includes: antivenom, botulism, rabies, & tetanus
Cell-Mediated Immune Response
The humoral immune response involves the production of antibodies and memory B lymphocytes.
What does the cell-mediated immune response involve?
»
T-cell activation
•
Like B-cells, T-cells must bind to their one, specific antigen before they are activated.
•
Unlike B-cells, T-cells cannot bind to free-floating antigens and must bind to an antigen-presenting cell,
like a macrophage.
»
Activated T cells will clone (multiply)
»
T cells will do their specific jobs
Types of T cells
»
Cytotoxic Ts ____________________________________________________________
___________________________________________________________________________
»
Helper Ts have many jobs
»
•
Encourage __________________________ of activated B cells and cytotoxic Ts
•
Encourage ______________________________________ from plasma cells
•
Release chemicals (lymphokines) which _____________________________and enhance activity of
phagocytes
Suppressor Ts
•
»
Release chemicals that _________________________________________________, to slow immune
response once antigen is destroyed
Memory Ts
•
Long-lived cells that remain for quick response upon subsequent infection
Why might helper Ts be thought of as the bridge between cell-mediated immunity and humoral immunity?