4. Lymphatic And Immune System Flashcards
What are the 4 main components of the lymphatic system?
Lymph, lymphatic vessels, lymph nodes and lymphatic organs (spleen, thymus, tonsils)
What are the 3 main functions of the lymphatic system?
- Returns fluid to the cardiovascular system
- Matures lymphocytes
- Transports fats and dietary substances absorbed in the small intestine
What do you call interstitial fluid when i enters the lymphatic system?
It becomes lymph
Where do the right and left lymphatic ducts drain?
Right duct drains into right subclavian vein, left duct drains into left subclavian vein
What is resistance?
ability to fight against or prevent disease
What is susceptibility?
lack of resistance
What is a pathogen?
living things that can cause disease (eg. bacteria,
viruses, parasites)
What is disease?
when pathogens invade cells and take over the cell’s
machinery, causing cells to no longer function properly
Can hijack the ribosomes in the cell so it makes proteins that the pathogen needs and no what you need, then kills the cell through lysis
What are the 2 parts of the immune system
Innate immunity and adaptive immunity
What are 3 examples of physical barriers in innate immunity?
Skin, mucous membranes and mucous
What are 3 examples of chemical barriers in innate immunity?
Gastric juices, acidic ph of skin, lysozyme in tears and saliva
What is flora?
Normal flora are microbes that establish fairly permanent residence but will not cause disease under normal circumstances
Large intestine has big flora
What is part of the first line of defense in innate immunity
Physical barriers, chemical factors
And normal flora
What is the second line of defense?
Phagocytes and natural killer cels, inflammation, fever, and antimicrobial substances
What are phagocytes?
White blood cells that engulf and digest pathogens
What type of lymphocytes kills infected cells in innate immunity?
Natural killer cells (NK cells)
What causes inflammation and its 4 symptoms/signs
Histamines are released to respond to injury to destroy invading pathogens, prevent spreading infection and begin repair.
The signs are redness, swelling, pain and heat (loss of function in severe cases)
Why is having a fever beneficial
It inhibits bacterial growth and speeds up immune response
Pathogens and cytokines cause release of prostaglandins
which reset the hypothalamus to an abnormally high body temperature
What is the 3rd line of defence?
Adaptive immunity: specialized lymphocytes (T cells and B cells) and antibodies
This is unique to each individual
What is the complement system?
A series of proteins that enhance the immune response
Act in a cascade, meaning one reaction triggers another and so forth (for amplification)
What are antigens
Foreign substances that trigger an immune response
What are the two branches of adaptive immunity?
Cell mediated immmunity (T cells)
And humoral immunity (b cells)
T cells mediated from Thymus
B cells mediated from Bone marrow
What type of cell activates both adaptive immunity pathways
Antigen-presenting cells (APCs)
What is an antigen presenting cell
An APC is a special macrophage that engulfs and break up the pathogen and then display some of the pathogens antigens on the outside of its membrane so other cells can detect it
How does the body recognize antigens?
- Free-floating pathogens can display their own antigens which can be detected by the immune system
- Special macrophages circulating in blood engulf and break up the pathogen and then “display” some of the pathogen’s antigens on outside of its membrane. Now called an antigen presenting cell (APC)
- Pathogens can escape detection by macrophages and infect cells which can respond by displaying some of the pathogen’s antigens on the outside of its membrane = flagging for help
What is the function of cytotoxic T cells?
They kill infected human cells
What happens when a T cells mediated is sensitized
It replicates and differentiates into earths a helper T cells mediated, a memory T cell or a cytotoxic T cell
What happens in the T cells mediated pathway when the antigen returns
The memory T cells from first time lie in wait, they will then differentiate into cytotoxic T cells quickly and kill infected. Cells. More memory T cells will also be made
What is the function of helper T cells
“helps” boost the process along by secreting
substances (cytokines) will activate b pathway if not already activated.
Which stem cells differentiate into B cells
Cells that remain in the spleen or liver
What do plasma cells produce
Antibodies
B cells can differentiate into plasma cells
What happens when a antigen invades the body in the B pathway
B cell is activated by free pathogen or helper T cell
B cell will differentiate into plasma cells or memory B cells. Plasma cells will rapidly produce antibodies specific to the antigen. Memory B cells act like memory T cells and remember the antigen
What happens when an antigen returns in the B pathway
Population of memory B cells lie in waiting
• When the antigen shows up again, the army of memory B cells rapidly differentiates into more plasma cells and memory B cells
What are the 4 functions of antibodies
- Opsonization: allows to be easily detected
- Agglutination: clumping/binding
- Neutralization: cannot cause disease
- Activation of complement system
What is immunological intolerance
The ability of the immune system to distinguish self from nonself and avoid attacking the body’s own tissue
When is immunological intolerance developed
During the maturation of lymphocytes
What is it called when you lose immunological tolerance
An autoimmune disorder
Self checking mechanisms malfunction
What is the purpose of vaccination
To induce a primary immune response without causing disease
What are the 5 types of vaccines
- Inactivated or killed (influenza,)
- Live attenuated (MMR)
- Toxoid (tetanus)
- Subunit (HPV, HEP B)
- mRNA (nuclei’s acid) ( covid19)
What does HIV (human immunodeficiency virus) lead to
AIDS (acquired immune defiency syndrome)
What type of immune cells does HIV destroy
Helper T cells
Why does AIDS weaken the immune system
Without Helper T cells, B cells and Cytotoxic T Cells cannot function properly
What types of infections become common in AIDS patients
Opportunistic infections
Without a strong immune system, become susceptible to infections
