3.3 Flashcards
1
Q
what is a histone?
A
a protein that DNA wraps around
2
Q
what is the epigenome?
A
all the chemical markers in an organism (on the DNA and histones)
3
Q
what is the attachment of methyl groups called?
A
methylation
4
Q
what does methylation cause?
A
causes chromatin to condense and prevent the gene from being expressed
5
Q
what does acetylation cause?
A
the chromatin becomes less tightly wound and the gene can be expressed
6
Q
when no lactose is present, what is binded to the operator and why?
A
the repressor, the lac genes don’t need to be expressed as enough glucose is present and RNA polymerase can’t bind to the promoter
7
Q
when lactose is present, what does it bind to?
A
the repressor
8
Q
what helps cells recognise other cells in tissues?
A
recognition proteins/adhesion molecules
