Molecular biochemistry W7

Question 1

How long does the adaptive system take to activate

Answer 1

days and weeks

Question 2

which one is slower the adaptive immune system or innate immunity

Answer 2

• Adaptive immune system

Question 3

Name the 2 main cells in adaptive immune system

Answer 3

B cells + T cells

Question 4

What do B cells differentiate into

Answer 4

• plasma cells

Question 5

What do plasma cells produce

Answer 5

Antibodies specific to antigens

Question 6

Name the 2 type of T cells

Answer 6

• Helper T cells
• Cytotoxic T cells

Question 7

What is the function of helper t cells

Answer 7

They activate other immune cells like macrophages and b cells

Question 8

What is the function of cytotoxic t cells

Answer 8

• They kill virus infected cells to prevent virus replication

Question 9

What does adaptive immunity create

Answer 9

• Memory B and memory t cells

Question 10

Explain how the memory B and t cells work

Answer 10

They remain dormant until reinfectio nwhere they are activated immediately, preventing reinfection

Question 11

What are antigens

Answer 11

proteins that trigger an immune response

Question 12

Name the 2 main regions of an antiboy

Answer 12

Variable region(top)
Constant region(bottom)

Question 13

What is teh function of the variable region of an antibody+ WHAT IS it called

Answer 13

• Binds to antigens
  -called idiotype

Question 14

What is the function of the constant region of an antibody+ what is it called

Answer 14

Performs immune function
-called isotype

Question 15

What do isotypes determine

Answer 15

• antibody class:
  igM, IgG, IgA,IgE,IgD

Question 16

When is IgM:
-produced
-lifetime
-What does it indicate

Answer 16

• produces in infection
• Short lived#
  -Indicated acute or revent infection

Question 17

When is IgG :
-produced
-Lifetime
-What does it indicate

Answer 17

• Produced later
  -long lasting
  -Indicates past infection or immunity

Question 18

What is the function of the IgA antibody+ where is it present

Answer 18

Protects mucosal surfaces
- present in milk

Question 19

What is thefunction of the igE antibody

Answer 19

• Fifhts against parasitic worms

Question 20

Name the main antibody in the blood

Answer 20

IgG

Question 21

Name the first antibody to be produced before the B cells

Answer 21

IgM

Question 22

What is the epitope

Answer 22

The part of the antigen recognized by the immune system

Question 23

What is the paratope

Answer 23

The part of the antibody that binds to the epitope

Question 24

What does thw binding of the paratope to the epitope depend on

Answer 24

The 3D shape

Question 25

What is Opsonization

Answer 25

- When antibodies help phagocytes by coating pathogens making them easier to engluf and destroy

Question 26

What are enzymes like papain and pepsin used for

Answer 26

To cut antibodies into function fragments FAB and fc

Question 27

What does Fab( fragment antigen binding) contain and what does it bind to

Answer 27

- Contains variable and constant domains of light and heavy chains -Binds to antigens

Question 28

What is Fc( fragment crystallizable) formed by+ what does it determine

Answer 28

- Constant heavy chain regions -Determines the isotype and biological function

Question 29

What is isotype determined by

Answer 29

- Fc region

Question 30

What is is idiotype determined by

Answer 30

Fab

Question 31

What is the variable region of the heavy changed formed by

Answer 31

- variable= 44 segents -Diversity- 27 segments Joining- 6 segments

Question 32

What is the recombinant VDJ gene recombinantion mediated by

Answer 32

VDJ recombinase

Question 33

Name the 2 step recombinayion process

Answer 33

- D- J joining -V to DJ joining

Question 34

What does the final V-D-J sequence code

Answer 34

The entire variable region

Question 35

Does the constant region neeed recombination

Answer 35

- No

Question 36

What happens instead of recombination in constant region and explain how this happens and what is produced

Answer 36

- It is transcribed and spliced The closest constant region to the VDJ is splices and them igM is produced by default

Question 37

Waht do light chain only use + names the 2 contstant regions it contains

Answer 37

- V and J segments - kappa and lambda

Question 38

When does isotype switiching occur+ under the influence of what and how is it done

Answer 38

After activation, under the influence of helper T cells By cutting out DNA between the VDJ and target constant gene

Question 39

Where does somatic hypermutation occur

Answer 39

Occurs in activated b cells

Question 40

What does somatic hypermutation introduce+ what does it lead to

Answer 40

Point mutatiosn in variable regioms -It leads to affinity maturation

Question 41

What happens in clonal selectiom

Answer 41

Antigens activate only specific B-cells with matching receptors. These B-cells proliferate, undergo mutation, and refine their antibodies.

Question 42

What is the purpose of ELISA

Answer 42

To detect antigen or antibodies in a patients sample

Question 43

Give exmaples of disorders elisa is used for

Answer 43

HIV HBV COVID

Question 44

wHAT is the whole principle of elisa test

Answer 44

That the antibody linked to an enzyme detects the presence of a target + when the substrate is added the enxy,e converts into a colorful product

Question 45

In direct elisa what does it use to detect an antigen

Answer 45

It detects antigen directly using an enzyme linke antobidy

Question 46

What happens in indirect elisa -What does it use

Answer 46

Uses a primary antibody to bind to the antigrn, then a secondary ensyme- linked antibody binds to the primary

Question 47

What does indirect elisa increase

Answer 47

Increases sensitivity

Question 48

What happens in sandwhich elisa

Answer 48

The capture antibody on the plate binds to the antigen , then a second antibody binds to it

Question 49

In lateral flow elisa what does the sample flow through

Answer 49

- Flow through pads containing anitbodes and if the antigen is presnet it binds to the anibodies

Question 50

Describe the 5 steps that occurs in a basic elisa

Answer 50

- Sample(blood) is added to well -Antigens if presnt stick to the well -Specific antiboys are added -Unbound antibodies are washed away -Substrate is added, rects w enxyme and colour change occurs if antigen is present

Question 51

Where are the VDJ and nearest constant region spiced together

Answer 51

At the mRNA level

Question 52

Once one functional heavy and light chain is made what happens to recombination and why

Answer 52

It is stopped to ensure 1 antibody specificity per b cell

Question 53

What is the function of terminal deoxynucleotide transferase - Tdt in relation to VDJ and what does this increase

Answer 53

It adds random nucleotides at VDJ junctions this increases antibody variability

Question 54

What is kept the same and what is changed in isotype switching

Answer 54

Idiotype stays the same but isotype is changed