Environmental Effects and Epigenetics Flashcards Preview

Molecules to Man > Environmental Effects and Epigenetics > Flashcards

Flashcards in Environmental Effects and Epigenetics Deck (10):
1

What are housekeeping genes

Genes that code for common structural proteins/enzymes

2

What are specialised genes

Genes that code for proteins that differentiate cells

3

How is transcription initiated

Basal machinery factors unwind DNA
TATA box indicated start site
General transcription factors bind + start transcription + recruit RNA polymerase

4

How is the gene regulated

Transcription factors receive messages from inside/outside of cells eg. phosphate levels

5

What determines the rate of transcription

Multiple enhances upstream/downstream
Transcription activators

6

Describe the structure of chromatin

Chromosome = One centromere. 2 telomeres
Histone Protein = Pack DNA into repeating DNA-Pn Particles
Nucleosome = 8 Histones and associated DNA

7

What is the function of histone modification

Carry information
Regulatory information
Layer of information that overlays DNA sequence

8

What do nucleosome modifications do

Turn genes on/off
Respond to changes in internal/external environment

9

What happens in X inactivation

1 of 2 X inactivated during early development
Inactivated X packaged into chromatin, condensed and turned into stone
Affects dosage compensation

10

Women have same X gene products as men but men only have 1 X chromosome. Why?

Gene dosage compensation = equalises gene expression levels