Transcript GenesEnv
Genes and the Environment
AP Biology
Fall 2010
The
environment contributes to
variations in gene expression amoung
individuals in a population
Fur
on the extremities of Himalayan
rabbits will be darker
This is because the enzyme for melanin
production will operate at cooler
temperatures but, is sensitive to heat on
the rest of the body
Cuttings
(come from the same parent plant)
from Yarrow plant clones grew differently at
three different altitudes
Cuttings from one plant grew tall at the
lowest and the highest elevation
But a third cutting remained short at midelevation
Even though these plants were genetically
identical, their phenotypes differed in
different environments
The
colour of the floral clusters on
Hydrangea will vary depending on the
acidity of the soil
Some
people tolerate stress better than
others
Perhaps due to differences in the gene
for a serotonin transporting protein
Serotonin compromises response to
stress
Understand
that environmental factors
can influence gene expression, know
some examples
How could this be a positive or negative
factor?
Would this have anything to do with the
nature/nurture debate?