Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology 3/4 > chap 7- acquiring immunity > Flashcards

chap 7- acquiring immunity Flashcards

You may prefer our related Brainscape-certified flashcards:
WSET ® Level 4 D2 Business of Wine flashcards AP® Biology flashcards Biology 101 flashcards
1
Q

is the third line of defence specific and acquired

A

yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the lymphatic system

A

a network of vessels, tissues and organs across the body that work together with the circulatory system and the immune system to fight infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the main roles of the lymphatic system

A

return fluid to blood
filter tissue fluid
be a site of antigen recognition
transport leukocytes around body
be a site of lymphocyte maturation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what do lymph nodes do

A

filters lymph and traps foreign particles, cellular wastes, toxins and pathogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what do the lymph nodes contain

A

lymphocytes (B and T cells), plasma cells, macrophages, dendritic cells and site where they encounter their antigens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the spleen

A

larger flattened organ located in upper left sector of abdomen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

where are lymphocytes located

A

throat, armpits, abdomen and groin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how are lymph nodes sites for antigen recognition

A

as lymph moves through the lymph vessels, the lymph nodes filter and trap invading pathogens and foreign matter. when an antigen is present in a lymph node it can be recognised by leukocytes of the adaptive immune system (lymphocytes) become activated and initiate a response.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does specific mean

A

specific to the pathogen presented

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

can third line of defense have memory

A

yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are the parts of the 3rd line of defense

A

lymphatic system, humoural response and cell mediated response.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are B lymphocytes involved with

A

humoral immunity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are T lymphocytes involved with

A

cell mediated immunity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what does cell mediated immunity target

A

intracellular pathogens, usually viruses that have broken through 1st and 2nd lines of defense and have gotten inside cells.
may also target self-cells that have turned cancerous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the types of T lymphocytes

A

helper T cells, cytotoxic T cells, memory T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what do helper T cells express once activated

A

MHC II markers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what do cytotoxic T cells do

A

initiate apoptosis in affected cells (similar to natural killer cells)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what do memory T cells do

A

contain “memory” of antigen and will differentiate into cytotoxic T-cells and proliferate if exposed to same antigen again

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are naive T lymphocytes

A

cells that havent yet encountered their specific antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what activates the cell mediated response

A

when a helper T cell encounters an antigen on an APC specifically to its antigen receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

do T cells directly bind to antigen

A

no they bind to antigens presented on MHC markers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are the steps in the cell mediated response

A

1- helper T cells bind on MHC II from APC
2- APC released cytokines which activate naive helper T cells which releases is own cytokines.
3- cytokines initiate proliferation/clonal expansion
4- cytotoxic T cells proliferae by dividing multiple times and forming an army of clones. some of these clones become effector ce;;s which are primed to destroy cells expressing the specific antigen that activated them
5- cytotoxic T effector cells release powerful cytotoxins directly into affected cells which work together to induce apoptosis in the target cell
6- other clones become memory cells which migrate in lymph nodes where they can be activated quickly if they come into contact with the same pathogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is clonal expansion

A

where multiple copies of T cell are produced and together release large amounts of cytokines designed to activate cytotoxic T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what happens if the same pathogen is encountered again after cell mediated immunity

A

Memory T cells that have migrated to lymph nodes are activated when they encounter the same pathogen and proliferate rapidly producing numerous copies of effector T cells.
This enables the pathogen to be fought off quicker

25
Q

where does the humoral response occur

A

the humors of the cell bodily fluids including blood, lymph and interstitial fluid

26
Q

what antigens does humoral response respond to

A

antigens on extracellular pathogens

27
Q

what does humoral response result in

A

the production of antibodies in B lymphocytes

28
Q

where do naive B cells form and mature

A

in the bone marrow and spleen

29
Q

what are antibodies in the humoral response

A

B cell receptors on B lymphocytes

30
Q

what are antibodies

A

quaternary proteins whih have a Y shape with 2 variable regions at the tips of the Y contain 2 identical binding sites that are complimentary to a specific antigen

31
Q

when does clonal selection occur

A

if B cell encounters an antigen in the lymph nodes that specifically matches with its antigen receptor

32
Q

what does the clonal selection theory propose

A

when B and T lymphocytes form, each has a receptor that is unique to them and that will react to a single antigen.

33
Q

when will a lymphocyte differentiate and proliferate into a clone of millions of effector cells

A

once it has been activated by its specific antigen

34
Q

what are the cloned effector cells dedicated to do

A

eliminate the specific antigen that stimulated the immune response

35
Q

what occurs during humoral response

A

1- a B cell is triggered when it encounters its matching antigen
2- the B cell engulfs the antigen and digests it
3- then it displays antigen fragments bound to its unique MHC molecules
4- this combination of antigen and MHC attracts the help of a mature matching T cell.
5- cytokines secreted by the T cell help the B cell to multiply and mature into antibody producing plasma cells.
6- released into the blood, antibodies lock onto matching antigens. the antigen-antibody complexes are then cleared by the complement cascade or by the liver and spleen.
7- once antibodies have ben released from the plasma B cell they can lead to the destruction of pathogens in 4 ways, all of which can occur simultaneously

36
Q

what is the alternative pathway

A

helper T cell with same receptor detects antigen displayed on MHC II marker of alternative APC.
Helper T cell releases cytokines which activate mature B cell with receptor specific to antigen
B cell undergoes clonal expansion and differentiation to produce plasma B cells and memory B cells
Plasma B cells release antibodies to locate and tag specific antigen

37
Q

how long can plasma B cells live for

A

a few days and can secrete up to 10000 molecules of a specific antibody per second into circulation.

38
Q

what is opsonisation

A

antibodies bind to antigens present on pathogen surface flagging them for destruction for phagocytes

39
Q

what is aggulation

A

variable regions of antibody can bind to 2 different antigens causing them to clump together in an antibody pathogen net immobilizing them and preventing spread of infection and making them susceptible to phagocytosis.

40
Q

what is cascade of complement proteins

A

antibodies that are bound to antigens can activate the cascade of complement proteins.

41
Q

what is neutralization of toxins

A

antibodies can neutralize toxins of antigens by preventing them from binding to their target

42
Q

how long can antibodies released by plasma B cells generally provide protection for

A

up to 28 days but the plasma cells tat secreted them can last for longer

43
Q

how long can memory B cells survive for

A

years or even a lifetime.
if they encounter the same antigen again, they can initiate a rapid response through proliferation to produce plasma B cells

44
Q

what immune systems do allergic reactions involve

A

both the innate and adaptive immune system

45
Q

what is the process of becoming allergic

A

1- allergen is injested or inhaled. recognised as ‘non-self’
2- innate immune system is activated
3- adaptive immune system is activated. B cells produce IgE antibodies
4- IgE antibodies attach to mast cells. these mast cells are now primed. the person is now sensitised
5- second exposure to the alleren- mast cells are activated and release lots of histamine
6- inflammatory response- watery eyes, itchy nose etc

46
Q

what is active immunity

A

results from the production of antibodies by the immune system in response to the presence of an antigen
takes time to develop, but the memory B and T lymphocytes ca provide immunological memory that can last a long time

47
Q

what is passive immunity

A

results from the introduction of antibodies from another person or animal
immunity is immediae but cannot be maintained as the immune system in the recipient is not activated against the antigen

48
Q

what is natural passive immunity

A

passive transfer of antibodies from mother to baby

49
Q

what is artificial passive immunity

A

injecting antibodies into person. temporary protection

50
Q

what is natural active immunity

A

get exposed to pathogen so person produces their own antibodies

51
Q

what is artificial active immunity

A

vaccines make you produce your own antibodies

52
Q

what is a live attenuated vaccine

A

involve a living microbe that has been weakened in the laboratory
e.g. chickenpox

53
Q

what are inactivated vaccines

A

‘killed vaccines’ contain microbes that have been inactivated by heat, radiation or chemical means
e.g. influenza

54
Q

what are subunit vaccines

A

contain part of pathogen whether that be the antigen itself or any molecule, such as proteins, peptides or polysaccharides
e.g. meningococcal

55
Q

what are toxoid vaccines

A

use toxins that have beeb inactivated t stimulate an immune response
e.g. tetanus

56
Q

what are messenger RNA (mRNA) vaccines

A

mRNA code triggers the body to make a protein unique to a virus, initiating an immune response
e.g. covid-19-pfizer

57
Q

what is a primary immune response

A

bodys first injection of vaccination

58
Q

what is secondary immune response

A

person after second injection of vaccination

59
Q

what is herd immunity

A

when enough of a population is immunized that the people who cannot be immunized are safe from infection

Biology 3/4 (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions