Brainscape's Knowledge GenomeTM

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


See full index

AS-Biology(*) > Immunology > Flashcards

Immunology Flashcards

1
Q

how does the immune system distungiush cells between “self” and “non-self”

A

antigens

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

what is the definition of an antigen

A

a foreign molecule, usually a protein, that stimuluates an immune response

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

True or False

Antigens have a specific shape and tertiry structure that is complementary to an anitbody

A

True

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

what is the non-specific immunity response

A

phagocytes

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

explain the process of phagocytosis

A
  • phagocytes move to the site of infection and engulf the pathogen. This forms a vesicle known as a phagosome
  • phagocytes contain many lyosomes which fuse with the phagosome
  • the hydrolytic enzymes called lysozymes in the lyosome hydrolyse the pathogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

explain the process of antigen presentation

A
  • after phagocytosis they display part of the pathogen on its cell surface membrane
  • this allows activation of other immune cells such as T and B cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the specific immune reponse

A

involves immune cells becoming activated in response to presence of a specific antigen of a pathogen

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

what does antigen presentation initiate

A

the cellular response

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

T helper cells

explain the first process of the cellular response

A
  • they have a receptor that has a complementary shape to the specific antigen
  • upon binding to the antigen, the T helper becomes activated and divides by mitosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

the activated T helper cells release ——-

A

cytokines

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

explain what cytokines do

A
  • stimulate B cells to divide by mitosis
  • stimulate phagocytes
  • stimulates cytotoxic T cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

explain the role of cytotoxic cells

A
  • contain receptors which bind to antigens on the surface of either virally infected or cancerous cells
  • the cytotoxic cells then release perforin which makes holes in the cell surface membrane of the cell
  • this leads to the cell undergoing apoptosis (cell death) and being destroyed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

involves antibodies

explain the humoral response

A
  • B cells are stimulated directly by the antigen binding to the receptors
  • or stimulayed indirectly by the release of cytokines
  • upon stimulation, the B cells divide by mitosis to produce clones
  • some of these B cells differentiate into plasma cells which produce and release large quantities of monoclonal antibodies. This is the primary response
  • some B cells become memory cells. This is the secondary response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

explain the structure of an antibody

A
  • quaternary protein where 4 polypeptide chains are joined together by disulphide bridges
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what happens when an antibody binds to its antigen

A

an antigen-antibody complex is formed

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

what is agglutination

A
  • antibodies bind to antigens
  • they clump them together
  • this marks the antigens and helps attract phagocytes
17
Q

what do vaccines contain

A
  • dead or weakened form of the pathogen
  • specific antigen
18
Q

explain how vaccines make use of the primary and secondary response

A
  • the stimulation of B cells will lead to the differentiation into plasma cells and the production of antibodies -primary response
  • memory cells are also produced - secondary response
19
Q

explain herd immunity

A
  • vaccinated individuals recover from an infection quickly
  • therefore less likely to spread the pathogen to unvaccinated individuals
20
Q

explain the steps of ELISA test

A
  1. monoclonal antibodies are fixed to the bottom of the test well
  2. a sample, potentially containing the antigen, is added to the well and will bind to the antigen-binding site on the antibody
  3. the well is washed with water
  4. a second monoclonal antibody is now added - which is attached to an enzyme - and will bind to another part of the antigen if present
  5. the well is washed again
  6. a substrate is added and the enzymes on the second monoclonal antibody will convert this to a different colour
  7. the colour change is a positive result
21
Q

give 4 key features of HIV

A
  • RNA genome
  • contains reverse transcriptase
  • genome is surrounded by a protein coat called capsid
  • the lipid envelope contains attachment proteins
22
Q

explain the replication of HIV

A
  1. attachment proteins on HIV bind to specific receptors on T helper cells
  2. viral RNA and reverse transcriptase enter the cell
  3. the reverse transcriptase converts viral RNA into DNA
  4. the viral DNA moves into the nucleus and is inserted into the host cell genome
  5. transcription of HIV DNA into HIV mRNA which is translated to produce HIV proteins
  6. the infected T helper cells starts to assemble new virus particles
  7. virus particles are released from the T helper cell
23
Q

how do antibiotics work

A
  • they prevent bacteria from synthesising murein cell wall
  • directly damage the cell wall
24
Q
A

AS-Biology(*) (22 decks)

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