Flashcards in Chapter 15 Deck (79):
A) What is the primary response?
frist response to a specific antigen: system remembers the action that proved effective against the antigen
B) What is the secondary response?
stronger antigen response is iplemented
C) What is humoral immunity and how does it work?
killing antigens in extrcellular ie in blood strezm/ tissue
1) What are B lymphocytes, where are they produced and what is their job? [Figure 15.1]
produced in bone marrow. They differentiate into plasma cells which then produce antibodies
3) What are antibodies and what do they do?
antibodies are y shaped protiens that attach to antigen. two arms attatch to the antigen (specific based on aa) and then the tail is a marker to signal other cells to aide in immune response. some have memory
4) What are B-cell receptors? [Figure 15.2]
receptors on b cell which if antigen binds to it know that it is to multiply and produce antibodies
D) What is cell-mediated immunity and how does it work? [Figure 15.1]
This is for intracellular immunity and gets rid of antigens that use cells as its host
1) What are T lymphocytes and where are the produced?
matures in the thymus. help eliminate antigens.
- What are the two subsets of T cells that eliminate antigens?
2) What does the T-cell receptor do? [Figure 15.2]
Dendritic cells take the antigen to the t lyphocyte which recognizes antigen with it's TRC and then will begin multiplying.
3) What regulatory T cells do?
They also aide in protecting self molecules.
4) What must happen before naive helper T cells and cytotoxic T cells can reproduce?
t cells must be activated by dendritic cell which will activate it.
6) What are TH cells and TC cells? [Cytotoxic T Cell Activity Against Target Cells]
Th- helper t cells: help in humoral(extracellular) immunity and activate b cells and macrophages to produce cytokines to support t cells
Tc- cytotoxic t cells: help with intracellular antigens and will trigger apotosis
A) What is the lymphatic system? [Figure 15.3]
system that brings b and t cells into contact with antigens
B) What is lymph? What vessels carry it? [Figure 15.4]
left over fluid from blood: contains wbc's and any antigens that have entered the system
C) What are some examples of secondary lymphoid organs and what do they do?
sites where lymphocytes gather to contact various antigens. lymph nodes, spleen, tonsils, apendix
1) What are Payers’ patches and where are they located? [Figure 15.5]
Secondary Lymphiod organ in intestinal tract. m cells take material to patches. part of mucosa associated lymphoid tissue.
D) What is the mucosa-associated lymphoid tissue?
system associated with prevention of mucous membrane.
E) What are skin-associated lymphoid tissues?
lymphiod tissues under skin
F) What are the primary lymphoid organs and what do they do?
bone marrow and thymus. where cells are made/ differentiated. b and t made in marrow. t matures in thymus
A) What is an antigen? [Antigen processing video]
any molecule that reacts specifically with an antibody
B) What is an antigen that elicits an immune response? [ImmResponse video]
C) How are T-dependant antigen different from other antigens?
T dependent are when the b cell needs a Th cell to become active.
E) What are epitopes? [Figure 15.6 and Antigenic Determinants Epitopes video
discrete regions of a molecule that are recognised by immune system aka antigentic determinants, some are aa, others are 3 d shapes that stick out of a molecule
A) What shape are antibodies? [Figure 15.7a]
they are all y shaped, but vary in light, and heavy chains.
1) Where are the FAB regions and what do they do?
2) Where is the Fc region?
arms of the y. They bind to antigens
B) What is the heavy chain and how many copies do antibodies have? [Figure 15.7b]
high molec. weight poly peptide chain. The vary
C) What is a light chain and how many copies do antibodies have? [Figure 15.7b]
lower weight poly peptide chain. 2domains
D) What is the variable region? [Figure 15.7c]
ends of the fabs, they are what make the antibodies anitgen specific.
1) What does the antigen binding site do?
binds to specific epitopes
E) What is the constant region? What does it do? [Figure 15.7c]
consists of part fo the Fc region as well as part fo the two fab regions. this allows other cells to recognize it
F) What are the six outcomes of antibody-antigen binding? [Figure 15.8]
Neutralization: when an antigen cannot do anything cause it is covered in antibodies
Opsonization: phagocyte eats it
Complement system activation: triggers compliment system which results in C3b initiating inflamatory response
Immobilization and Prevention of adherence: antibodies bind to flagella imobilizing it, and binding to pilli prevents it from attatching
Cross liking: When 1 antibody can bind to 2 antigen molecules linking them, and creating a bigger bite for the phagocytes
Antibody- dependent cellular cytotoxicity: IGg molecule bind to virally infected cell and becomes a target fo NK cells
G) What are the five major classes of immunoglobulins and what are their characteristics? [Table 15.1]
IgM-5-13% of cir. antibodies. made in primary response. lrg so it cannot leave blood stream. Most effective in triggering Complement System, and cross links antigens
IgG- 80%-85 of serum immunoglobulin. Llongest term prtection. half like of 21 days. Most abundant in 2nd response. provides protection via all 5 responses
IgA- 10-13% in serum. produced by plasma. it is the most commmon innunoglobin. It is important in mucosal immunity
IgD-- 1% of all serum immunoglobulins- involved in maturation of antibodies
IgE- tightly bound to basophils. gets rid of paradites. It can bind to harmless food causing the mast cells to respond by releasing histamine resultin in allergy symptoms.
1) Where do infants get their IgG pre vs. post
pre- placenta post post- colostrum of first breast milk produced.
2) What is secretory IgA? How is it different from IgA?birth? [Figure 15.9]
It is a dimer. It is a nuetralizer adn it also is huge in mucosal immunitiy. it is different cause it has a peptide on it
A) What is the clonal selection theory? [Figure 5.10 and Clonal Selection video]
??????treis to describe how we have an infinite array of antibodies. the b cells are produced before they even expirience a specific eppitope.
C) What are immature lymphocytes?
have not fully developed their antigen specific receptors
D) What are naive lymphocytes?
antigen receptors, but have not yet encountered their antigen
E) What are activated lymphocytes?
sense antigen and can respond
F) What are effector lymphocytes?
produce specific cytokines
G) What are memory lymphocytes?
lond lived descendants of activated lymphocytes and are quickly activated we=hen encounter antigen
A) What happens when a B cell’s antigen receptor binds to a T-dependent antigen?[T Cell dependent antigens video]
Thye bring in the antigen via endocytosis and then they are broken into peptide fragments. These fragments are then delivered to protien structure MHC class II molecules. These move tot he Bcell surfave where they present pieces of the antigen for inspection by Th cells.
B) What are MHC class II molecules and what are they for?
they are ptoeins that move segments of antigen to the cell surface
1) What is antigen presentation? [Figure 15.11]
when an antigen segment from B cell is presented to the Th cell
C) How long does it take for antibodies to accumulate in the first exposure to an antigen? [Figure 15.12]
1) What happens during this delay? [Figure 15.13]
The B cells will bind to antigen and present fragments to Th cells. Once activated the B cell will mulitply. They also will from anitibody- secreting plasma cells.Each plasma cell only survives for several days. Then Bcells undergo changes.
D) What is affinity maturation? [Figure 15.14]
natural selection amound proliferating B cells. The ones that multiply are the ones that can bind to antigens for longer durations.
E) What is class switching? [Figure 15.15]
cytokines switch b cells genetic programing causing it to secrete another antibody
F) What are memory B cells?
live without the antigen and are used in secondary response. they become this after class switching
G) What is secondary response?
faster than primary- response to antigens it has been exposed to
H) What do T-independent antigens do? Why are they significant? [Figure 15.16]
can activate b cell without the help of a Th cell. they can infect younger kids because they have polyshacharides in a nice arrangement that clusters of bcell receptors can bind to and activate
A) What are the characteristics of T cells? [Table 15.2]
B) What is the T-cell receptor made of? [Figure 15.7]
has 2 shory polypeptide chains each with a variable and constant region.
C) How do T-cell receptors interact with antigens?
they cannot find free antigens they must be brought to them. They are then laid in protien groove of MHC molecules on the surface of the presenting cell. The t cells then read the MHC with the antigen.
1) What are the two classes of MHC molecules and how do they differ? [Figure 15.18]
MHC I: present to Tc cells amd carries endogenous antigengs
MHC II: Th recognise these- carry exogenous
E) What are CD markers used for?
used to distinguish between tc and th cells. they are different protien makers. c8 =tc marekerscd4- th
F) What are dendritic cells and what do they do? [Figure 15.20]
scouts of innate immunity: they bring antigens to the t cells!
1) What are co-stimulatory molecules used for?
Dendritic cells mature when carrying a pathogen to a t cell. they develop proteins that act as emergency signal telling the t cell that the material being presented is dangerous
2) How do dendritic cells cross present?
they can present ot both MHC1 and MHC2 and therefore activate Tc and Th cells.
G) When do you Macrophages and B cells activate T cells?
They cna present antigens to the MHC2 and encourage memory T cells
H) What do Tc cells do?
induce aptosis in infected or cancerous self cells.
1) How do they distinguish infected or cancerous cells from normal cells? [Figure 15.21]
cells routinely will take apart own proteins and present them on the surface. If peptides are normal Tc cells should not recognize them.
I) What do TH cells do?
Orchestrate immune rsponse by activating B cells and macrophages... they also direct these and T cells
1) How do these cells activate B cells?
b cell binds to antigen and takes it iin and then breaks it down into peptides. These are loaded into MHC2 molecules. If Th cell recognizes it, it delivers cytokines to activate B cells to undergo class switching and some to form memory B cells.
2) How do conjugate vaccines work?
attatch a protien molecule covalently to form a t dependent antigen. This molecule is taken in by the Bb cell and then presents to Th cells. This causes the T cell to start b cell activation and subsequent antibodies to be made.
3) What are haptens?
molecules that bind to a b cell receptor yet doesn't ellicit antibody production. ie penicillin
4) How do people develop an allergy to penicillin?
H influenzae conjugate vaccine is very similair to penicillin. This can cause IgE antibodies to form which can late come in contact with penicillin and result in an alergic reaction.
5) How do TH cells activate macrophages? [Figure 15.2]
the macrophage brings it int the cell and degrades it and them presents it on MHC2 molecule and then Th releases cytokines to activate the macrophage
6) What happens when macrophages are activated?
it enlarges, the plasma membrane becomes irregular, the cell increases metabolism producing more lysosomes. It also produces nitric oxide. if this si not sufficient they will form giant cells
7) How are giant cells formed and what do they do?
this is when macrophages fuse together. these also can fuse with T cells froming granulomas. This prevents infectous microbes from escaping. ie helpful with tb
J) What are the subsets of dendritic cells and effector helper T cells and what do they do?
idff types of dendritic cells that steer immune system to appropriate response. each produce cytokines that activate Th cells to differentiate
A) What do natural killer cells do? [Figure 15.23]
They induce aptosis. They are developed from lymphiods progenetors. Their Fc receptors bind to the red flag portion of receptors.
1) What have recent studies indicated about cells?
found that NK cells are more than killers because they can create cytokines based on their local environment.
A) What do descendants of hematopoietic stem cells become? [Figure 15.24]
B and T cells
1) Where are B cells made?
made in bone marrow
2) Where are T cells made?
made in bone marrow and then develop in the thymus
B) How is the great diversity of antibodies generated? [Figure 15.25 and Antibody diversity video]
C) What negative selection do B cells go through?
any b cells that bind to self