#7: Epigenetics

Question 1

Epigenetics

Answer 1

Chemical markers and protein located on the DNA that determines gene expression

Signals from outside world can work through epigenome to change cell’s gene expression

Question 2

Epigenome learns from experience

Answer 2

Epigenetic tags record cell’s experiences helping to stabilize expression

Signals come from inside cell, neighbouring cells, outside world

Some genes turned off/on, are turned up/down

• methyl group inhibit expression
• acetyl group activate gene

Question 3

Epigenetics & inheritance

Answer 3

A parent’s experiences, in the form of epigenetic tags, can be passed down to future generations

Epigenetic inheritance adds another dimension to the modern picture of evolution

The genome changes slowly, through the processes of random mutation and natural selection. The epigenome can change rapidly in response to signals from the environment.

Epigenome remains flexible as environmental conditions continue to change

Question 4

Wild radish

Answer 4

When attacked by caterpillars, produce distasteful chemical

Offspring produce same traits even if caterpillar- free environment

Question 5

Water flea

Answer 5

Females respond to chemical signals from predators by growing protective helmet

Offspring also grow helmets

Question 6

Lab Rats

Answer 6

Vinclozolin is fungicide used on grape plants

Feeding it to pregnant rats causes lifelong changes to offspring and next generation