IMIN Lecture 7

Question 1

B-cells develop into

Answer 1

IgM B+ cells

Question 2

How is an infinite number of receptors generated?

Answer 2

diversity is generated by somatic recombination

Question 3

How is the gremlin organized?

Answer 3

Genomic DNA
Transcription->splicing
mRNA-> protein

Question 4

Heavy chains contain

Answer 4

V segments
D segments
J segments

Question 5

Light chain contains

Answer 5

κ and λ, lacks D gene segments

Question 6

Splicing from C region of RNA

Answer 6

IgM heavy chain

Question 7

first recombination vs. second

Answer 7

1st-germline

2nd- no germline recomb.

Question 8

What region is changed by recombination and which remains the same

Answer 8

unique variable region

conserved constant region

Question 9

What is junctional diversity

Answer 9

rearrangement of B-cell genes by addition or removal of nt

Question 10

B-cells activate when

B-cells die when

Answer 10

They have a second signal

No second signal

Question 11

How do T cells help B-cells

Answer 11

stimulate B cells to begin cloning

Question 12

What can happen to B-cells after activation?

Answer 12

Some become cloning, some differentiate into antibody secreting plasma cells, memory cells
or class switch

Question 13

How is the second response different from first?

Answer 13

smaller lag, higher response, more IgG or IgE/heavy chain class switching, higher affinity
->can be change in gene leading to aa change

Question 14

All mature B-cells start out making

Answer 14

IgM

Question 15

DNA encoding causes ____of constant region

Answer 15

some constant region deleted

Question 16

New class generated by

Answer 16

exposed DNA ends joined together

Question 17

Class switching does not affect

Answer 17

Variable region

Question 18

Class switching DOES effect

Answer 18

constant region